Bai Arcgis

I HC QUC GIA H NI TRNG I HC KHOA HC T NHIN TRN QUC BNH

BI GING

ESRI ArcGIS 8.1(Dng cho sinh vin ngnh a l - a chnh )

H NI - 2004

Mc lcPHN I. CC KIN THC C BN BI 1. Gii thiu v phn mm ArcGIS 8.1 BI 2. Qun l d liu bng ArcCatalog BI 3. Gii thiu chung v ArcMap BI 4. To d liu BI 5. Cc phng php hin th d liu BI 6. Trnh by bn (layout a map) 1 8 13 17 25 32

PHN II. MT S KIN THC NNG CAO BI 7. Chuyn i gia cc nh dng d liu BI 8. Lnh truy vn hi - p (queries) BI 9. Tm kim khng gian BI 10. Geoprocessing wizards BI 11. 3D Analyst BI 12. Spatial Analyst 39 44 47 52 56 62

Bi 1. Gii thiu v phn mm ArcGIS 8.1

Trong bi ny chng ta s hc v:

ArcMap xy dng, hin th, x l v phn tch cc bn ArcCatalog qun l, theo di cc d liu c hoc to mi v m t cc d liu mi ArcToolbox cung cp cc cng c x l, xut - nhp d liu t ArcView sang cc nh dng khc nh MapInfo, MicroStation, AutoCAD, ... ArcMap l ng dng dng to ra cc bn . Mi mt bn trong ArcMap c gi l Map document, mt bn c th c mt hay nhiu data frames. Data Frame l mt nhm cc lp (Data layer) cng c hin th trong mt h qui chiu. Thng thng, mt bn n gin ch c 1 Data Frame v bn cn s dng nhiu Data Frame khi cn in thm mt s bn ph trn 1 mnh bn chnh (xem bi hin th d liu). Bn (Map document) c ghi trong file c ui l .mxd.Scale

Giao din ngi dng (ArcCatalogue, ArcMap, ArcToolbox) File bn (c ui l *.mxd) Lp thng tin (Data layers) v cc i tng (data features) Cc chc nng c bn v bn Cc bng thuc tnh (Attribute Tables) Cc chc nng c bn lm vic vi cc bng Cc trang v cc nhm thng tin (Layouts/data frames)

Kin thc nn:Phn mm ArcView bao gm 3 ng dng (application) chnh sau:Data Frames

View control tools Select tools Data View

Data Layers

TOC

Help Text line

Data / Layout View switch

Coordinates display

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Bi ging ArcGIS 8x. 2004. Trn Quc Bnh

Trong hnh v trn, mt bn c tn l "Exercise.mxd" c 2 data frame l "Layers" v "New Data Frame". V phn mnh "New Data Frame" gm 3 lp (layer) l "Grid", "81.pgn" v "awscntry". Tt c cc thng tin trn ta nhn thy trong pha bn tri mn hnh, c gi l TOC (table of contents - mc lc). Bn thn ni dung bn c hin th trong ln bn phi, ty theo ch m c gi l Data View hay Layout View. Mi mt lp c th tt hoc bt trn mn hnh bng cch nh du vo vung nh (checkbox) bn phi tn ca n trong TOC. Trong hnh v trn c 3 lp ca "New Data Frame" u c bt. V tr v kch thc hin th ca bn c th c thay i bng cc cng c phng to, thu nh (Zooming) v dch chuyn (Panning). T l ca bn (trong hnh v trn l 1:557902) c hin th trong gia pha trn mn hnh. Nhiu chc nng thng dng c th c tm thy thng qua context menus (thc n nhanh, hin th thng qua cch bm chut phi vo i tng quan tm). Cn ch l cc i tng trong bn c 2 loi: Feature c lu tr trong c s d liu v Graphic element khng c lu tr trong CSDL. Graphic Element thng l cc i tng dng trnh by bn nh khung, thc t l, ch gii,... chn Feature ta dng cng c "Select Feature", cn chn Graphic Element ta dng "Select Element" trn thanh cng c Tools (bn phi mn hnh). Mt Feature c th c chn (select) nu n nm trong lp c tnh cht l "Selectable Layer". tt bt tnh cht ny c th vo thc n Selection Set Selectable Layer. Thng tin thuc tnh ca cc i tng (feature) c lu tr trong cc bng thuc tnh gi l attribute table. Mi feature class hay shapefile c 1 (v ch 1) bng thuc tnh. Mt bng c to bi cc dng (record) v cc ct hay trng (column hay field). Mi mt feature c 1 v ch 1 record trong attribute table. xem attribute table ca mt layer no ta bm chut phi vo tn ca n trong TOC ri chn Open Attribute table. ArcMap c 2 ch hin th: Data View v Layout View. Trong Data View ch hin th cc feature, tc l ni dung chnh ca bn . Layout View hin th bn trong ch nh chng ta s in ra trn giy, trong ngoi cc feature cn c cc Graphic element l cc yu t trang tr bn nh khung, li ta , ch gii,... Trong Data View bn ch c th lm vic c vi 1 Data Frame 1 thi im, cn trong Layout View bn c th lm vic ng thi vi nhiu Data Frame

(xem bi hin th d liu) Cc bn ch c th c chnh sa trong ch Data View. chuyn gia cc ch hin th vo thc n View.

Bi tpBc 1. M mt bn c Khi ng ArcMap t nt Start Programs ArcGIS ArcMap

Chn thc n File Open Trong hp thoi hin ra tm th mc c:\ArcGIS_course\ ri m file Bai_1.mxd Bm OK, bn s c m.

Bc 2. Nghin cu bn , thay i t l v dch chuyn ca s

Cc cng c hin th bn gm: - Phng to (Zoom in) v thu nh (Zoom out) - Phng to / thu nh theo tm ca mn hnh (Centered zoom) - Phng to ht c (Full extent) v dch chuyn (Pan). theo 2 cch khc nhau: C th s dng cng c phng to (Zoom in) - Bm chut vo ch bt k, Data View s phng to thm 25%, - Bm chut vo mt im bt k, khng nh chut ra ko n i ch khc to thnh 1 hnh ch nht ri nh chut ra. Ton b ni dung bn gii hn bi hnh ch nht s c phng to ht c cho kn mn hnh.

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Zoom in

Zoom out Zoom in/out to the center of the map

Pan

Zoom to full extent of the map

Go to previous/next extent

a chut vo thanh cng c Tools (hnh v trn) ri nghin cu cc dng tr gip (tool tip) m t tng cng c. Bm vo cng c Zoom In. Kim tra 2 ch lm vic ca cng c ny (bm vo 1 im hay to 1 hnh ch nht trn bn ). S dng cng c ny hin th ton b lnh th Vit Nam. T l lc ny l bao nhiu ? ri dch chuyn bn nhn thy Thi Lan ri tr Bm vo cng c Pan li cu hi: Ta a l ca thnh ph Bng Cc l bao nhiu: Kinh : ......... E V : ......... N

Bc 4. Xem thng tin v cc i tng

Mi mt lp (layer) u c mt bng thuc tnh i km m t cc i tng (feature) ca lp . xem thng tin thuc tnh ca mt i tng no ta c th m bng Attribute Table hay dng cng c Identify. Bm vo cng c Identify

Bm chut vo chm trn biu th th trn Sn Ho: Ca s Identify results s hin ra:

Bc 3. Tt / bt cc lp (layer), cng c Zoom to layer Trong TOC (Mc lc - Table of Contents) tm lp c tn l "Cities". Hy th tt lp ny bng cch bm vo vung nh bn cnh n. Bm chut phi vo lp Populated Places (khu dn c) hin th context menu: Chn Zoom to layer ri theo di thay i trn mn hnh. Tn ca khu dn c gia pha trn mn hnh l g ? Tn l: .

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Ca s ny hin th tt c cc thng tin v i tng lp trn cng () m ta va bm chut vo.

Bm vo nt c mi tn bn tri ch :

Ca s Set Selectable Layers s hin ra:

Trong danh sch hin ra chn Bm vo th trn Sn Ha trn bn mt ln na, ca s Identify results s hin th nhiu layer hn. Hy tr li xem tn ca cc layer (lp) l g: ; . ; ; .

Bm nt Clear All Tt c cc layer s tr v trng thi khng phi l selectable. Bm vo bn cnh lp Populated places v Roads ri ng ca s li. Cc lp ny s tr thnh selectable (c th chn c). Bm vo cng c Select Feature: Trn bn bm vo vng trn hin th th trn Son Hoa. i tng (th trn) s c nh du bng mt chm ln mu xanh. Bm vo mt ng mu en no bn cnh Son Hoa. ng s c chn (chuyn sang mu xanh) thay cho th trn Sn Ha. Hy th bm vo mt i tng no khng phi l ng hay khu dn c ri tr li xem c s kin g xy ra khng?

Bc 5. Chn i tng (Select a feature)

Trc khi lm vic vi mt hay mt nhm i tng no ta cn phi chn chng. chn i tng ta c th s dng cng c Select Feature (hay bng cc hi p - query s c nghin cu trong bi sau). Lu rng ch c cc i tng trong cc Selectable layer mi c th c chn. Vo thc n Selection Set Selectable Layers

Ty theo ch chn c t trong thc n Selection Interactive Selection Method, khi ta bm vo mt i tng no th n c th: 1) cBi ging ArcGIS 8x. 2004. Trn Quc Bnh

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thm vo danh sch cc i tng c chn, 2) loi khi danh sch hay 3) tr thnh i tng c chn duy nht. Trong thc n Selection Interactive selection method chn Add to current selection Bng thuc tnh s c m:

Bc 7. Thm trng (add field) v thay i gi tr trong bng thuc tnh

Trn bn bm chut vo vi ng v khu dn c. Cc i tng c chn c vn tip tc c chn nh c khng ? Trong thc n Selection chn Clear selected features .

Cu trc v ni dung bng thuc tnh c th c thay i trong trong phin bin tp ca ArcMap (edit session, s c ni n trong cc bi sau). Ngoi ra cc thng tin thuc tnh cn c th c sa cha ngoi Edit section, tuy nhin trong trng hp ny ta khng th dng lnh Undo ( hy cc thay i a vo bng thuc tnh) nh trong Edit section c. Trong ca s Attributes of Cities bm nt Options ri chn Add field (xem hnh trn).

Ta thy cc i tng c chn s tr v trng thi khng c chn na. Hy th th nghim vi 3 ch cn li trong Selection Interactive selection method.

Bc 6. M bng thuc tnh (Attribute table)

Nh trn ni, mi mt lp (chnh xc hn l 1 feature class) c mt bng thuc tnh lin kt vi n m t cc i tng trong lp . Hy m bng thuc tnh ca lp Cities nh sau: Bt lp Cities bng cch nh du vung nh cnh n trong TOC. Bm chut phi vo lp Cities trong TOC Trong thc n hin ra chn Open Attribute Table Trong hp thoi hin ra Name g My_field, trong danh sch Type chn Text (trng dng ch), ri trong Length g 30 l s ch ti a ca trng ny

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Trn mn hnh s hin ra hp thoi cnh bo rng lnh Undo s khng th thc hin c. Bm nt Yes ng hp thoi ny li v tip tc. Trong hp thoi Field calculator hin ra g Thanh pho" + [City_Name] (xem hnh di).

Bm OK Ko bng thuc tnh dch sang 1 bn nhn r bn . S dng cng c Zoom hin th trn bn mt vi thnh ph (k hiu bng vng trn nh mu ). Vo thc n Selection Set Selectable Layers ri cho php cc i tng ca lp Citites c th c chn. Bm vo 1 thnh ph no chn n (vng trn tr thnh mu xanh). rng dng tng ng ca thnh ph trong bng thuc tnh cng c chn (bi xanh). Bm vo nt Selected trong bng thuc tnh ch hin th cc i tng c chn. Trong bng thuc tnh ch cn li 1 dng:

Bm nt OK. Xem gi tr trong trng My_field va mi to. Bm nt All trong ca s bng thuc tnh hin th tt c cc dng ca bng ny. Hy quan st cc gi tr trong trng My_field thy rng ArcMap ch thc hin tnh ton cho cc i tng c chn. Hy chn 2-3 thnh ph cng mt lc ri thc hin cc lnh trn mt ln na.

Bm chut phi vo trng My_field va c to bc trc. Trong thc n hin ra chn Calculate values

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Bc 10. Sp xp cc dng, to Alias Alias - tm gi l tn lng, l mt tn gi khc ca cc trng, thng dng d nhn ra ni dung ca trng hn. V d nh trng TD c th t Alias l "Thua dat" d hiu hn. Tn trng khng c du cch, cn Alias th c th c.

sp xp cc dng theo th t tng dn (ascending) hay gim (descending) ca cc gi tr trong mt trng no ta lm nh sau: M bng thuc tnh ca lp Cities Bm nt All hin th tt c cc dng

Bc 8. Xa trng trong bng thuc tnh Sau khi nghin cu xong, trng My_Field khng cn dng na nn chng ta s xa n i. Trong bng thuc tnh bm chut phi vo tn ca trng My_field n ri chn thc n Delete Field. ArcMap s cnh bo l lnh Delete Field khng th Undo c. Bm Yes tip tc.

Bm chut phi vo tn trng CITY_NAME (ta mun sp xp tn cch thnh ph theo th t ABC) Trong thc n hin ra (context menu) chn Sort Ascending hay Sort Descending

Bc 9. Tm cc i tng c chn

Do mn hnh khng th hin th ht c ton b bn nn c th mt s i tng no tuy c chn nhng b khut khng nhn thy c. hin th chng ta dng cng c Zoom to Selected: ng bng thuc tnh Bm chut phi vo lp Cities trong TOC Trong thc n hin ra chn Selection ri sau Zoom to Selected. Hy quan st nhng thay i hin ra. ng bng thuc tnh li.

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Bi 2. Qun l d liu bng ArcCatalog

Ty thuc vo loi d liu m ArcCatalog th hin chng di dng cc biu tng (icon) khc nhau. Mt s loi d liu nh Shape file l mt tp hp nhiu file khc nhau nhng ch c hin th bng 1 Icon duy nht. Hnh v sau minh ha ch Content view trong ArcCatalog:

Trong bi ny chng ta s hc v:

Kt ni vi th mc (Connecting to folders) t cc tnh cht ca th mc Xem xt (duyt) d liu, xc nh loi d liu (data types) Ch Contents view Ch xem s b d liu (Data Preview) Ch Metadata view Lm vic vi d liu Khi ng cc phn mm khc ca b ArcGIS t ArcCatalog

Navigating and connecting to folders

Controlling data preview

Launching other applications

Preview control Viewing contents data types

Previewing data as geographic or table view Viewing metadata information about a dataset

Kin thc nnArcCatalog cung cp cc phng tin bn xem, qun l cc d liu a l v cc bng d liu thuc tnh. C 3 ch khc nhau xem d liu: Contents, Preview v Metadata view. - Trong ch contents view tt c cc d liu m ArcView c th nhn dng c s c hin th di dng cy th mc (catalogue tree) hay cc biu tng (icons) ging nh chng trnh Windows Explorer. - Bn cng c th xem s b (preview) cc d liu a l di dng bn (geographic view) hay di dng bng (table view). Lu rng mt CSDL a l bao gm cc i tng c xc nh bi v tr a l v thng tin thuc tnh trong bng attribute table. - Trong ch Metadata View bn c th xem cc d liu dng metadata, tc l cc thng tin m t khc nhau v d liu nh h qui chiu, thi gian v phng php thu thp,... Cc dng d liu m ArcView c th nhn dng c bao gm cc feature data sets: shape file, ArcInfos coverage file, Personal Geodatabase v CAD files (*.dwg, *.dxf v *.dgn) v cc file nh raster nh *.tif, *.jpg, *.gif, *.bmp, *.png, *.img, ...

Point dataset

Line dataset

Polygon dataset

Trn hnh v sau l ch Preview, cc d liu c th hin di dng bng thuc tnh.

Feature IDs

Feature attribute NAMES

Bm vo trang Metadata chuyn sang ch Metadata view ta c hnh v nh sau:

Feature attribute VALUES

Chuyn t dng Table sang dng Geography ta thy c bn sau:

D liu metadata c lu tr trong file c tn cng tn vi file d liu chnh nhng c ui l *.xml, v d file_name.xml

Bi tpBc 11. Kt ni vi th mc Mc ch ca vic kt ni vi th mc l c th truy nhp nhanh vo th mc khi lm vic vi ArcView (tng t nh vic to Shortcut trong Windows). Trong hp thoi hin ra tm th mc C:\ArcGIS_course ri chn n. Bm OK. Bm nt Connect to folder:

Th mc ny s c to shortcut trong cy th mc (Catalog tree) bn tri mn hnh:

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Chn th mc C:\ArcGIS_course\DCW Bm vo tng nt trong s 4 nt trn ri quan st cc thay i trn mn hnh. Ch rng Thumbnails (hnh v nh hin th ni dung ti liu mt cch s b) ch hin ra i vi nhng ti liu c to sn thumbnail trc . Cc ti liu khng c thumbnail th c hin th di dng Icons hay tn ca chng. Cch to Thumbnails xem bc sau.

Bc 13. Lm vic vi Preview view Bn c th ngt b cc kt ni to. V d nh th mc ( a) C:\ khng cn thit na c th ngt i: Bm vo "C:\" trong cy th mc ca ArcCatalog chn n. Bm nt Disconnect from Folder ngt kt ni.

Preview view hin th ni dung ca ti liu bn chn trong cy th mc (Catalog tree). Bn c th chn 2 dng hin th l Geography (ch p dng vi d liu khng gian) v Table (nu bn ci 3D Analyst extention th cn c thm ch 3D view na). chuyn i gia cc dng ny hy s dng listbox pha di mn hnh ca ArcCatalog:

Th mc C:\ s bin mt khi cy th mc Bc 12. Lm vic vi Contents view Bm vo trang Preview ri th xem mt s d liu trong th mc C:\ArcGIS_Course\.

Ch Contents view hin th cc ti liu c trong th mc m bn chn cy th mc (Catalog tree). Ti liu c th l mt hay nhiu file. Contents view hin th cc ti liu ny di 1 trong 4 dng tng t nh trong Windows Explorer: large icons (biu tng to), list (danh sch), details (chi tit) hay thumbnails (hnh v nh hin th s b ni dung ti liu). Bn c th chuyn gia cc dng ny bng cc nt trn thanh cng c Contents:

Khi xem d liu di dng Geography bn c th s dng cc cng c phng to, thu nh (zoom), dch chuyn (pan) hin th v to Thumbnail ( ni n trong bc trn). Trong Catalog tree chn shapefile Admin: C:\ArcGIS_course\DCW\Admin.shp Vo trang Preview v chn ch hin th Geography. S dng Zoom in phng to 1 phn no ca Admin.shp. Bm nt Create Thumbnail to thumbnail cho file ny Hy s dng cc cng c Zoom v Pan:

Large icons List Details

Thumbnails

Hy nghin cu cc dng hin th ny bng cch:

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Trong Catalog tree chn th mc C:\ArcGIS_course\DCW ri bm vo trang Contents, sau chn ch Thumbnail view (xem bc 2) xem hnh thumbnail m bn va to.

Bc 14. Lm vic vi cc lp (layers)

Layer l t hp cp cao ca d liu. Mt layer file cha cc ni dung sau: - ng dn ti d liu (shapefile, geodatabase...); - Cc tham s hin th d liu nh mu sc, lc nt, k hiu,... Nh vy vic dng layer rt tin li do chng ghi nh c cc tham s hin th d liu (nu ch dng d liu khng th mi ln dng chng ta li phi chnh cc tham s hin th). Cc file layer thng c ui l *.lyr. Bn c th to v s dng layer trong c ArcMap v ArcCatalog. Trong bc ny bn s to layer cho feature class v cc nc ng Nam . Mi nc s c hin th bng mt mu ring bit. Trong ArcCatalog hy: Chuyn vo th mc C:\ArcGIS_course\DCW\ Bm vo trang Preview. Trong cy th mc, bm chut phi vo file Country.shp ri chn thc n Create Layer. Trong hp thoi hin ra g Cac_nuoc_DNA ri bm nt Save. Trong cy th mc, chn layer Cac_nuoc_DNA m bn va to. Bm vo 1 file bt k trong cy th mc ri bm li vo Cac_nuoc_DNA ( ArcCatalog load li d liu), bn s thy mi nc trn bn s c t mt mu.

Cc bc tip theo t cc tham s hin th cho layer Cac_nuoc_DNA (tc l cho d liu trong shapefile Countries.shp) Bm chut phi vo layer Cac_nuoc_DNA ri chn Properties. Trn mn hnh s hin thi ra hp thoi Layer Properties (hnh di) Bm trang Symbology. Bm vo Categories, trong danh sch m ra bm tip vo Unique Values Value Field t gi tr CNTRY_NAME (trng cha tn nc ca shapefile Country.shp) Bm nt Add All Values a tt c cc nc vo trong danh sch Bm nt OK ng hp thoi Properties.

Bc 15. Lm vic vi layer trong ArcCatalog v ArcMap

Bn c th dng cc thao tc ko-th (drag and drop) chuyn cc layer hay cc feature class t ArcCatalog sang ArcMap. Trong bc ny bn s khi ng ArcMap t ArcCatalog ri to layer bng cch ko cc feature class t ArcCatalog. Trong ArcCatalog bm nt Launch ArcMap trn thanh cng c, bm OK to mt Workspace mi. Dch chuyn ca s ArcCatalog v ArcMap sao cho chng so le nhau ta c th ng thi lm vic vi chng:

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rng mc d trn ta thay i cch hin th lp Countries trong ArcMap song cch hin th " Cac_nuoc_DNA" trong ArcCatalog vn khng thay i. Trong TOC ca ArcMap, bm chut phi vo Cac_nuoc_DNA ri chn Save as Layer File Tm vo th mc C:\ArcGIS_course\DCW ri ghi li layer vo file Lower48.lyr ng ArcMap Trong ArcCatalog bm vo trang Contents ri chn thc n View Refresh Chn Lower48.lyr ri bm vo trang Preview, ta s thy cc nc c hin th ging nh trong ArcMap ban ny.

Trong ArcCatalog, bm ri ko layer C:\ArcGIS_course\DCW\Cac_nuoc_DNA sang TOC ca ArcMap

Bc 16. Lm vic vi d liu

Khi cc bn ko 1 layer t ArcCatalog sang ArcMap th bn s c 2 layer ging nhau ch khng phi l 1 layer chung. Nu bn thay i cc tham s hin th ArcCatalog s khng nh hng n layer m bn chp sang ArcMap. Trong ArcMap, bm chut phi vo layer Cac_nuoc_DNA Chn Properties, trong thc n hin ra bm vo trang Source

Trong ArcCatalog bn c th to mi, di chuyn, xa cc th mc v file d liu ging nh trong Windows Explorer bng cc lnh New, Copy, Paste, Delete,... Trong ArcCatalog bm vo trang Contents Bm chut phi ri chn New Folder i tn th mc mc nh t "New Folder" thnh "MyNewFolder" Trong cy th mc, bm chut phi vo Cac_nuoc_DNA layer ri chn Copy Bm 2 ln vo th mc MyNewFolder m n ra ri bm chut phi, chn Paste, Cac_nuoc_DNA s c chp vo th mc mi to. By gi bn hy th xa tp Cac_nuoc_DNA va mi chp vo bc trc.

rng d liu cho layer ny vn l file shape file "Country" ch khng phi l "Cac_nuoc_DNA.lyr" m bn to bc trc. Tip theo y chng ta s hin th tt c cc nc bng cng 1 mu trong ArcMap: Bm trang Symbology Bm vo Features (Nh l trong phn trn chng ta bm vo Categories), ArcMap s t ng chn phng php Single Symbol Bm nt OK. Tt c cc features ca lp Countries s c hin th bng cng mt mu Quay tr v ArcCatalog, bm vo th mc C:\ArcGIS_course\DCW trong cy th mc. Vo thc n View Refresh Chn Cac_nuoc_DNA trong trang Contents ri bm vo trang Preview

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Bi 3. Gii thiu chung v ArcMap

v nu ta thm vo bn mt lp (chng hn nh ng giao thng...) c xc nh trong h HN-72 th ArcMap s t ng chuyn tm thi lp v h VN-2000 hin th ng trn bn cng vi cc d liu khc. Bn thn cc tp tin cha lp va thm vo th vn khng thay i, tc l vn trong h HN-72. Mi bn c th c 1 hay nhiu data frame. Mi data frame c th c mt h qui chiu ring. Cc data frame c hin th ring bit trong ch Data View v c th hin th chung trong ch Layout View (xem bi hin th d liu). Cc layer c th c to ra t nhiu ngun d liu khc nhau: shape files, personal geodatabases, ArcInfo cover datasets, CAD drawings, SDE databases, tables, photo hay images. Cc d liu a l c 2 dng chnh l vector (shape, cover, CAD, geodatabase,...) v raster (nh s, nh qut, cc file nh di dng *.jpg, *.tiff, ...) Shape file v Geodatabase l 2 dng d liu vect chnh ca ArcViews. D liu trong mt shape file (hay mt feature class trong geodatabase) ch c th l mt trong s 3 dng i tng sau: point (im), line (ng) v polygon (area vng). Khi bn to mt shape file trong ArcCatalog th bn phi ch r n s cha cc i tng loi no (khc vi ArcView, MapInfo cho php bn lu tr trong mt file c 3 dng i tng trn).

Trong bi ny chng ta s nghin cu v:

To mt bn Thm d liu vo bn v data frame (data frame c hiu l nhm cc lp c hin th vi cng mt c s ton hc, mt bn c 1 hay nhiu data frame, 1 data frame c 1 hay nhiu lp - layer) Thuc tnh ca cc i tng (feature attributes) Tnh cht ca Data frame v bn Chuyn nhanh h qui chiu (Projecting on-the-fly) Ghi bn Khi ng cc chng trnh khc t ArcMap

Kin thc nnArcView tch hp cc thng tin a l v thng tin thuc tnh trong cc lp d liu (data layers) v hin th chng trn bn . D liu bn trong ArcMap c th xem di 2 ch : Data View v Layout View. Cc lp d liu (Data layers) v tham s ca chng c nhm thnh cc Data frame v c ghi li trong file bn . thm layer vo trong bn ta c th s dng nt "Add Data" hay dng ng tc ko-th t ArcCatalog (xem bi 3). Cc lp trong ArcMap c th c loi b bng cch bm chut phi vo tn ca n trong TOC (TOC - Table Of Contents, xem bi 2) ri chn remove trong thc n hin ra. Nu trong bn c nhiu layer th chng s c v theo th t t di ln trn theo danh sch trong TOC. V d nh nu 2 layer cng hin th mt vng th layer di s b ln bi layer nm trn. thay i th t ca layer ta c th bm chut ri ko n n v tr mi trong TOC. ArcMap c chc nng project on-the-fly cho php thay i mt cch nhanh chng h qui chiu ca cc layer. V d nh ta c mt bn trong h ta VN-200013

Bi tpBc 1. t h ta cho shapefile rdline.shp ng ArcMap nu n ang chy Chy ArcCatalog nu n cha chy Trong ArcCatalog tm n th mc C:\GIS_course\ArcMapDemo\shape Bm vo trang Contents ri bm chut phi vo file rdline.shp ri chn Properties. Trong hp thoi hin ra chn trang Fields Bm vo trng Shape trong danh sch Field Name:


Trong ca s Browse for Coordinate System tm Geographic Coordinate Systems World ri chn h WGS84

Trong na di ca hp thoi s hin ra bng cc tham s Field Properties ca trng Shape. rng tham s Spatial Reference ca trng Shape hin ang l Unknown (h ta cha xc nh). Bm nt dng Spatial Reference (hnh trn)

Ca s Spatial Reference t tham s ca h qui chiu s hin ra (hnh di). Bm nt Select

Bm nt Add ng ca s li Bm nt OK trong ca s Spatial Reference Properties ng n li. Bm tip nt OK trong ca s Shapefile Properties

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By gi shapefile rdline.shp c t h qui chiu cn thit. Bc 2. Chy ArcMap v to mt bn mi Khi ng ArcMap t nt Start hoc bng cch bm vo biu tng ArcMap trn thanh cng c ca ArcCatalog Trong hp thoi hin ra bm OK to mi mt bn .

Trong Select Coordinate System chn h qui chiu sau: Predefined Geographic Coordinate Systems World WGS1984 (ging nh bc 1) Bm nt OK ng hp thoi Data Frame Properties li.

Bc 3. t cc tham s cho Data frame Trong th mc (TOC) ca bn va to c 1 data frame c tn mc nh l Layers. Data Frame ny hin cn ang rng (hnh di).

T gi tr i bn s c hin th trong h to a l WGS-84. Nu bn thm vo Data Frame (tc l thm vo bn ) cc d liu trong h qui chiu khc th chng s c t ng chuyn i v h WGS-84. i tn cho Data Frame Layers v chn n v hin th ta cho n lm cc bc sau: Bm chut phi vo Bm vo trang General Trong Name g "WGS84" i tn ca Data Frame Trong Display chn Degrees Minutes Seconds hin th ta di dng - pht -giy. ri trong thc n hin ra chn Properties.

Bm chut phi vo

ri trong thc n hin ra chn Properties.

Trong hp thoi hin ra bm vo trang Coordinate System (hnh di).

trn mn hnh data frame Layers c i tn thnh WGS84. Ta ca con tr chut cng c hin th pha di bn phi mn hnh bng pht - giy.Bc 4. Thm d liu t shape file v coverage file Bm nt Add data t thanh cng c ca ArcMap

Tm th mc C:\GIS_course\ArcMapDemo\shape ri thm c 3 file (pppoint.shp, pppolyp.shp, rdline.shp) trong bng cch gi nt Ctrl trn bn phm ri bm chut vo tng file mt, sau bm nt Add. D liu trong 3 shape file s c thm vo data frame Layers v hin th ln mn hnh. Do cc shape file pppoint.shp v pppoly.shp c t trong h quy chiu khc vi WSG-84 nn s c hp thoi yu cu khng nh chuyn i h ta ca cc file ny v h WSG-84 ca Data Frame WGS84. Bm nt OK chp nhn chuyn i. Bm nt Add data mt ln na. Tm th mc C:\GIS_course\ArcMapDemo\cover ri nhy p chut vo file pop_areas (cc khu dn c). Cc thnh phn ca pop_areas s hin ra, bn s thy coverage file pop_areas cha cc i tng dng ng, ch gii, vng v im (arc, label, polygon, tic). Bm phm Ctrl ri chn c 4 loi i tng: arc, label, polygon, tic.

15


Bm nt Add thm chng vo bn .

Chng ta c th nhn thy rng 2 layer l pop_area polygon v pppolyp cha cc i tng ging ht nhau. pop_areas polygon ng trn pppolyp trong mc lc (TOC) nn n s che khut cc i tng ca pppolyp. Tt v bt lp pop_areas polygon thy rng lp pppolyp cng ging ht n (cc vng dn c nh trn bn i mu khi tt / bt)

tt New Data frame v bt WGS84, trong TOC bm chut phi vo data frame WGS84 ri chn thc n Activate. New Data frame s tt i v trn mn hnh s hin th ra data frame WGS84 (ch m).

Bc 6. nh hng ca vic thay i h qui chiu

Bc 5. To mt data frame mi Chn thc n Insert Data Frame

Sau y chng ta s thm vo bn mt layer tn l UTM_zones cha li kilomet trong li chiu UTM: Bm nt Add data ri thm file layer C:\ArcGIS_course\ArcMapDemo\UTM_zones. trong th mc

Tip theo chng ta s nghin cu nh hng ca vic thay i ta : xut hin trong TOC. l cc layer ca Data Frame WGS84 khng hin th trn mn hnh na (do trong ch Data View, ArcMap ch hin th 1 Data Frame trong 1 thi im, l Active Data Frame tn ca n c vit bng ch m trong TOC). Bm chut phi vo New Data Frame ri chn Properties, trong hp thoi hin ra vo trang Coordinate System. t h ta l Predefined Projected Coordinate System UTM OtherGCS trong bc 3). Bm nt OK ng hp thoi Properties. Bng cch s dng nt Add data : Th mc C:\GIS_course\DCW C:\GIS_course\ArcMapDemo\image country.shp Esrimap (file nh) File , ln lt thm cc file nh sau vo (khc vi h WGS-84 ta t Trong ArcMap, bm chut phi vo UTM_zones ri chn Zoom to Layer Hy tr li xem li ta c hnh g ? Dng chut ko layer UTM_zones t data frame WGS-84 sang data frame New Data Frame Bm chut phi vo New Data Frame ri chn Activate Bm chut phi vo UTM_zones ri chn Zoom to Layer hin th ton b layer ny trn mn hnh. Li ta by gi c hnh g? Bn c bit ti sao khng ?

Bc 7. Ghi bn Trong ArcMap Chn thc n File Save as Tm n th mc C:\GIS_course ri g tn file bn l Bai_3, bm nt Save. ArcMap s t ng thm ui .mxd ri ghi bn vo a cng.

Ta s thy trn bn hin ra cc nc ng Nam v nh ca khu vc Sng Hinh (nh rt nh so vi c nc Vit Nam).

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Bi 4. To d liuGeoDatabase

Trong cc bi trc chng ta lm vic ch yu vi nh dng d liu Shape file. Trong bi ny chng ta s lm quen vi mt nh dng d liu khc l GeoDatabase. Cc bn s hc cch to c s d liu di dng mt GeoDatabase trong c cc Feature Data Set, Feature Class. Ngoi ra, cc bn cng hc cch v v chnh sa cc i tng hnh hc trong CSDL .

Feature Dataset

Feature Dataset

Feature Dataset

Feature Class

Feature ClassAttribute Table

Feature ClassAttribute Table

Kin thc nnC 2 nh dng ArcMap dng lu tr d liu l shape files v personal geodatabase (gi tt l geodatabase). Shape file n gin hn GeoDatabase song chc nng ca n li t hn. 1. Shape file lu tr c d liu khng gian ln d liu thuc tnh. Ty thuc vo loi i tng khng gian m n lu tr, shape file s c hin th trong ArcCatalog bng 1 trong 3 biu tng (icon) sau:im Vng ng

Attribute Table

Trong GeoDatabase c 1 hay nhiu Feature Dataset. Feature Dataset l mt nhm cc loi i tng c cng chung h quy chiu v h ta . Mt Feature Dataset c th cha 1 hay nhiu Feature Class. Feature Class chnh l n v cha cc i tng khng gian ca bn v tng ng vi 1 lp (layer) trong ArcMap. Mi Feature Class ch cha mt dng i tng (polygon - vng, Line - ng, point hay multipoint- im). Mt Feature Class s c gn cht vi 1 bng thuc tnh (Attribute Table). Khi bn to Feature Class th bng thuc tnh cng c t ng to theo. Mt v d v CSDL bn a chnh: Feature Class Geometry type Attribute Description

V thc cht shape file khng phi l 1 file m l 5-6 file c tn ging nhau nhng ui khc nhau (bn c th xem chng trong Windows Explorer). 3 file quan trng nht ca shape file l cc file c ui: *.shp cha cc i tng khng gian (geometry) *.dbf bng thuc tnh *.shx ch s lin kt i tng vi bng thuc tnh nu c file *.prj th n s xc nh h qui chiu ca shape file.

GeoDatabase "Ban_do_dia_chinh" Feature Dataset "Ban_do". Coord. system: VN-2000 Thua Ranh_thua Tam_thua Polygon Line Point Point Point Line dien_tich, so_hieu, loai_dat so_hieu, X, Y, Z Ten, mo_ta So_hieu_manh dien_tich, so_hieu, loai_dat Hin th tha t Hin th ranh gii tha t Hin th tm tha t Hin th im khng ch o v Cc im c trng Khung ban do

2. GeoDatabase l mt CSDL c cha trong mt file c ui l *.mdb (nhdng ca MS Access). Khc vi Shape file, GeoDatabase cho php lu gi topology ca cc i tng. Cu trc ca mt GeoDatabase nh sau:

Diem_khong_ch e Diem_dac_trung Khung_BD ...

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3. nhp d liu hay chnh sa chng bn phi khi ng Edit Section(phin bin tp) trong ArcMap. ArcMap c y cc cng c bn c th v cc i tng bn . Tt c cc cng c c b tr trong thanh Editor ToolBar, thanh ny c th c gi ra thng qua thc n Tools Editor ToolBar hoc View Tools Editor:

Bi tpTrong bi ny bn s th to mt CSDL bn a chnh vi 2 feature class l Thua v Ranh_thua (xem bng trn). Sau bn s v 1 mnh bn vi s v cc s liu cho trong hnh v trn. Bc 1. To GeoDatabase v Feature Dataset Khi ng ArcCatalog Vo th mc C:\ArcGIS_course\CadastralMap Vo trang Contents ca ArcCatalog, bm chut phi vo ch trng bt k ri chn thc n New Personal Geodatabase (hnh di)

Mt c im ca ArcMap l khi v mt i tng hnh hc, bn phi s dng cng c Sketch (bt phc ha) v phc ha. Sau khi phc ha xong i tng bn ra lnh "End Sketch" th hnh phc ha mi tr thnh i tng tht trong CSDL. Tuy nhin, cc i tng ny vn cha c ghi vo file ca CSDL trn a cng. Sau khi kt thc mt phin Edit (Edit section), bn phi ra lnh Save Edits th nhng g bn lm mi tht s c ghi vo file CSDL trn a cng.

ArcCatalog s to mt Geodatabase vi tn mc nh l "New Personal...", hy g tn mi cho n l "DiaChinh" ri bm Enter. Bm p chut vo DiaChinh, do hin nay CSDL cn cha c i tng no nn n cn trng. Bm chut phi vo ch trng bt k ri chn New Feature Dataset. Trn mn hnh s hin th ra hp thoi Feature Dataset (hnh di). Name hy g "UTM-48" l tn ca Feature Dataset.

18


Bm OK ln na ng hp thoi Feature Dataset. ArcCatalog s to 1 Feature Dataset c tn l UTM-48

Bc 2. To cc Feature Class "Thua" v "Ranh_Thua" Nhy p vo Feature Dataset c tn l UTM-48 va to m n ra, bn s thy hin nay trong Feature Dataset ny cha c g. Bm chut phi vo ch trng bt k ri chn New Feature Class Trong hp thoi hin ra (hnh di) g "Thua" Name

Do h ta cha t nn trong Spatial Reference c dng Unknown Coordinate System. t ta cho Feature Dataset va to hy bm vo nt Edit. Trong hp thoi hin ra bm vo nt Select chn mt h ta c sn Trong hp thoi "Browser for Coordinate System" vo th mc Projected Coordinate System\UTM \ WGS-84 ri tm file "WGS 1984 UTM Zone 48N.prj". Bm nt Add. Trong hp thoi Spatial Reference Properties bm vo trang X/Y Domain ri t cc gi tr MinX=500000, MaxX=600000, MinY=2300000, MaxY=2400000 nh hnh v di Bm nt Next Trong hp thoi tip theo khng cn sa g c. Bm tip nt Next Trong hp thoi tip theo (hnh di) lit k cc trng ca Thua. Bm vo trng Shape, trong danh sch hin ra pha di Geometry Type chn Polygon. Spatial Reference c sn h ta m ta t bc 1 cho Feature Dataset WGS-84.

Bm OK ng hp thoi Spatial Reference Properties

19


Bm nt Finish, ArcCatalog s to Feature Class c tn l "Thua". to Feature Class "Ranh_Thua" cng lm cc bc tng t nh i vi "Thua" song Geometry Type l Line (ch khng phi l Polygon) v khng cn to thm trng mi nh "So_hieu" trong bc trc.

Bc 3. Chy ArcMap v to bn mi Hy ng ArcCatalog li v khi ng ArcMap ri to mt bn mi. Bm nt Add Data ri tm vo C:\ArcGIS_course\CadastralMap\DiaChinh\UTM48\ ri m 2 feature class "Thua" v "Ranh_Thua" m ta va to bc trn. Vo thc n Tools Editor ToolBar hin th thanh cng c Editor:

Sau y chng ta s thm trng thuc tnh "So_hieu" cho feature class "Thua". Hy bm chut vo trng ngay di trng "Shape" ri g "So_hieu" (hnh di), bm vo bn phi n (ct Data Type) ri chn kiu d liu l "Short Integer".

Bm vo nt Editor ri chn Start Editing bt u Edit Section (phin bin tp). Bm tip vo nt Editor ri chn Snap Option trong ca s hin ra nh du tt c cc ct Vertex chn ch bt im vo nh ca cc ng v vng (hnh di). nh du c Edit sketch vertices.

ng ca s Snapping Environment.

Trc tin chng ta s to cc ng ranh gii tha lp "Ranh_Thua". Bi vy trong Target hy chn "Ranh_Thua".Bc 4. V cnh ABIK Trong Task ca thanh cng c Editor chn "Create New Features"

20


Bm vo cng c Sketch

bt u v phc ha ArcMap s v on IK di dng phc ha. a chut v ch gn im A, con tr s t ng bt im vo A. Bm chut tri dng nt cnh KA. Bm chut phi ri chn Finish Sketch (hay bm phm F2). ArcMap s dng cc i tng l ng ABIK

Bm chut phi vo ch trng bt k, trong thc n hin ra chn Absolute X,Y G ta ca im A vo ca s ta nh trong hnh v sau ri bm Enter

Bm chut phi vo ch trng bt k, trong thc n hin ra chn Absolute X,Y G ta ca im B vo ca s ta nh trong hnh v sau ri bm Enter

Bc 5. V cc cnh BCDEFGNM ArcMap s v on AB di dng phc ha. Do t l trn mn hnh cn rt nh nn im A v B gn nh trng nhau. Hy dng cng c Zoom In phng to khu vc gn cc im ny. Sau y chng ta s dng cnh BI. rng cnh BI vung gc vi AB v c chiu di 80m. Bm tip vo Sketch tools tip tc v phc ha rng BC l cnh ko di ca AB, tc l song song vi AB v i qua im B. Do ta c th v BC nh sau: Dng cng c Edit Bm vo Sketch chn cnh AB ri snap chut vo im B, bm chut tri

a chut v 1 im bt k trn cnh AB, bm chut phi, chn thc n Parallel. By gi on thng s dng s ni tip vi AB Bm chut phi gn v tr d kin ca im C ri chn Length. G chiu di 120m ri bm Enter. Cnh BC s c dng phc ha.

Bm chut phi vo ch trng bt k ri chn Deflection... (gc tnh t cnh AB va to). Trong ca s nh hin ra g 90 l gc vung cn dng ri bm Enter: Tip tc dng cc cnh CD, DE, EF, FG, GN, NM tng t nh i vi cnh BI bc trn. Khi dng cnh FG nu ArcMap dng khng ng hng (chy v 0 pha cnh CD) th thay gc bng 270 hay g chiu di l -30m. Bm phm F2 Finish Sketch. n y chng ta dng c hnh sau:

ArcMap s gii hn ng mi to gc 90 so vi cnh AB. Bm chut phi vo ch trng bt k gn v tr cn dng im I ri chn Length... Trong ca s nh hin ra g 80 l chiu di cnh BI ri bm Enter

0

ArcMap s v on BI di dng phc ha. dng im K ta rng s gia ta ca n so vi im I cng bng s gia ta ca A so vi B. Do ta s s dng cng c Delta X,Y dng im K. Bm chut phi vo ch trng bt k ri chn Delta X,Y... ri g -100, -50. Bm Enter:

21


Dng cng c Edit Bm vo Sketch

chn cnh NM

Snap chut vo im M ri bm chut tri a con tr chut vo im bt k trn cnh NM ri bm chut phi, chn 0 Segment Deflection, g gc 135 vo hp thoi hin ra, bm Enter. V 1 cnh theo hng ML c chiu di bt k. Bm F2. Dng cng c Edit chn cnh va to

Trong Task chn Extent/Trim features Bm vo Sketch Snap chut vo im A ri bm chut tri Snap chut vo im K ri bm chut tri Bm chut phi, chn Deflection ri g gc 0 ko di cnh AK Ko di ng thng cho ct qu cnh theo hng ML (dng bc trn) ri bm chut tri (hnh di). Cnh ML s c dng.0

Bc 6. Dng IH v GH dng IH v GH ta cn bit im H. Trn s u bi ta thy H l giao im ca KI v NG. Bm vo mi tn cnh Sketch (hnh di) ri chn cng c Intersection

a con tr chut v 1 im trn cnh KI, ArcMap s v 1 ng thng di chy qua , bm chut tri. a con tr chut v 1 im trn cnh NG, ArcMap s v 1 ng thng di chy qua , bm chut tri. im H l giao im ca KI v NG s c dng. Bm vo Sketch HG s c dng. ri bt im vo im G. Bm chut tri ri phm F2. Cnh Trong Task chn Create New Feature ri dng tip cnh KL. Bm F2.

Dng tip cnh HI ni H v I (nh bm F2 khi kt thc).

Bc 8. Dng cc cnh DT, TP, PQ, NP, MQ Bc 7. Dng cnh ML im M l giao im ca ng nm di gc 135 vi cnh NM v ng AK. dng im M lm cc bc sau.0

Cnh DT dng tng t cnh BC. Cnh TP v PQ dng tng t cnh CD vi chiu di tng ng l 50+30=80m v 100m.

22


Cnh NP dng bng cch ni N vi P. Cnh MQ dng bng cch ni M vi Q.

Trong Task chn Extent/Trim features ri dng im S tng t nh cch dng im L bc trn. Hoc bn c th dng cng c Intersection dng im S tng t nh im G.

Bc 9. Dng ng USR

Cnh US song song vi CD v cch n 20m, tng t cnh RS song song vi QP v cch n 20m. Trc tin ta phi ct ng gp khc BCDEF c th tch ra on CD ( c th copy parallel). Dng cng c Edit chn ng gp khc BCDEF

Bm vo cng c Split trn thanh cng c Editor:

Snap ri bm chut tri vo im C, ng gp khc BCDEF s b ct thnh 2 on C. Dng cng c Edit chn ng gp khc CDEF

Bm vo cng c Split trn thanh cng c Editor: Snap ri bm chut tri vo im D, ng gp khc CDEF s b ct thnh 2 on D v ta c on CD cn c. Dng cng c Edit chn cnh CD

Trong cc bc trn ta v xong lp ranh gii tha. Trong cc bc tip theo ta s v cc tha t. v cc tha t (l i tng vng trong ArcMap) ta c nhiu phng php khc nhau. Bn c th s dng cng c sketch v vng bng cc phng php tng t nh trn ta dng v ranh gii tha. Tuy nhin trong bi ny chng ta v ton b ranh gii tha nn y ta s tn dng chng v cc tha t. Nguyn tc chung khi v cc i tng dng vng trong ArcMap l ta phi v phc ha c ng bao ca chng. Trong cc bc tip theo chng ta s s dng cng c Trace "chy" theo cc ng ranh gii tha nhm to ra ng bao . Chng ta cng s s dng cng c Autocomplete Polygon nng cao hiu sut v tng chnh xc. u im ca cng c Autocomplete Polygon l khi c cc tha t k nhau (cng chung ranh gii) v ta v mt s tha th khi v cc tha bn cnh khng cn phi v li ng ranh gii chung na. Do cc tha t nm trong Feature Class "Thua" nn trong cc bc tip theo ta phi chuyn Target layer v "Thua".Bc 10. Dng tha ABIK bng cng c Trace Trong Target thanh cng c Editor chn "Thua", Task chn Create New Feature (hnh di).

Bm nt Editor ri chn Copy Parallel, trong hp thoi hin ra g -20 vo Distance (du "-" copy ng hng)

Bm nt OK, im U v mt phn ca ng US s c dng Lm tng t nh trn ta s c im R v mt phn ca ng RS

Dng cng c Edit

chn ng ABIK

Bm vo mi tn cnh cng c Sketch ri chn cng c Trace Bm chut vo im A (khng cn chnh xc) a chut chy chm vng quanh ng ABIK (hy ng mu en rt mnh chy theo con tr chut), khi quay v im A th bm chut tri ln na.

23


Bm F2 Finish sketch. Tha ABIK s c to ra v c t mu (hnh di).

ng bng thuc tnh

Bc 14. Kt thc phin Edit Bm vo nt Editor trn thanh cng c Editor ri chn Save Edits ghi cc kt qu vo CSDL. Bm vo nt Editor trn thanh cng c Editor ri chn Stop Editing. Nu bn khng lm bc trc (Save Edits) th khi Stop Editing, ArcMap s hi bn c mun ghi li nhng g lm khng. Khi bn c th chn Yes hoc No. Ghi li bn vo file C:\ArcGIS_course\BandoDC.mxd.

Ch : thay v cng c Trace bn c th chn cng c Sketch ri bt im vo A, B, I, K

Bc 11. Dng tha BCDEFGHI bng cng c Auto Complete Polygon Trong Task chn Auto Complete Polygon. Chn cng c Sketch Bt im ri bm vo B, tip tc bt im ri bm vo C, D, E, F, G, H, I Bm F2 Finish sketch. Tha BCDEFGHI s c dng. Ch : do ta dng cng c Auto Complete Polygon nn cnh IB chung vi tha ABIK ( c t bc trc) khng cn v li.

Bc 12. Dng cc tha cn li

Bng cng c Auto Complete Polygon tng t nh i vi tha BCDEFGHI bc trn. Trong qu trnh dng bn c th kt hp s dng cng c Trace.Bc 13. nh s tha Vo bng thuc tnh ca lp "Thua". trong bng c 2 trng l Shape_Length (chu vi) v Shape_Area (din tch) c t ng tnh. Ln lt chn tng tha (trong bng thuc tnh hoc trn bn ) ri g s hiu tha vo trng So_hieu nh sau: ABIK s 1, BCDEFGHI s 2, DTPNGFE s 3, PNMQ s 4, NGHIKLM s 5.

24


Bi 5. Cc phng php hin th d liu

Trong bi ny chng ta s lm quen vi cc phng php hin th d liu nhm nng cao tnh trc quan ca chng. Chng ta cng s hc cch to nhn (label) cho cc i tng trn bn . Ngoi ra bn cn th thay i mt s k hiu c sn to ra nhng k hiu mi.

Kin thc nnD liu c th c hin th trn bn bng nhiu phng php khc nhau. Mi phng php c c trng bi k hiu, mu sc, lc nt, ng bao... Ty theo loi d liu v mc ch s dng m ngi ta chn cch hin th cho ph hp. Cn ch rng tt c cc i tng trn cng mt lp th u phi hin th theo cng mt phng php. ArcMap h tr cc phng php hin th sau: 1. Single Symbol: Tt c cc i tng u c hin th theo cng 1 kiu. Phng php ny c dng hin th cc d liu n gin hay dng nghin cu mt phn b ca cc i tng dng im. 2. Categories: Cc i tng c hin th bng mu sc hay k hiu khc nhau da trn gi tr ca mt (hay nhiu) thuc tnh no . Thuc tnh c s dng lm c s hin th c gi tr ri rc vi s lng khng qu 20-30 gi tr, chng hn nh 1, 2, 3, ... hay "Hanoi", "Haiphong",... C 3 ch hin th bng Categories l 1. Unique values; 2. Unique values, may fields; 3. Match to symbols in style. Trong Unique values l hay c s dng nht, chng hn nh hin th cc loi hnh s dng t bng cc mu sc khc nhau, hay trn bn hnh chnh cc a phng c t mu khc nhau. Match to symbols in style dng hin th bng cc style t trc (c th lm vic vi cc style t thc n Tools Style Manager). 3. Quantities: Cc i tng c hin th bng mu sc hay k hiu khc nhau da trn gi tr ca mt (hay nhiu) thuc tnh no . Khc vi phng php Categories, thuc tnh c s dng lm c s hin th c gi tr lin tc hay ri rc vi s lng gi tr ln. Chng hn nh khi th hin m hnh s cao hay th hin mt dn c 1 khu vc no . ArcMap s chia cc gi tr c th c thnh tng khong ri t cho mi khong gi tr mt loi k hiu. Bn c th thay i s lng cng nh ranh gii ca cc khong. Cc loi k hiu c th s dng i vi phng php Quantities l:

- Graduated color: Cc khong gi tr c hin th bng mu sc khc nhau. - Graduated symbols: Cc khong gi tr c hin th bng k hiu c kch thc khc nhau. - Proportional symbol: mi gi tr c hin th bng k hiu c kch thc t l vi gi tr . Nh vy Proportional symbol s hin th chnh xc hn Graduated symbols song n c tnh khi qut ha km hn v khng thch hp khi thuc tnh c rt nhiu gi tr (lm ri mt). - Dot Density: Thuc tnh c th hin bng cc im c mt khc nhau. Gi tr cc cao th mt cng ln. 4. Chart: gi tr ca mt tp hp cc thuc tnh dng s c th hin bng biu . V d nh c cu s dng t ca tng khu vc c th c hin th bng phng php ny. 5. Multiple Attributes: Ging nh phng php Quantities Graduated color song p dng cho mt tp hp cc thuc tnh. Bn c th t cc phng php hin th m t trn cho tng layer (lp) bng cch bm chut phi vo tn ca layer trong TOC (table of contents, bn tri mn hnh, xem bi 1) ri chn thc n Properties. Trong hp thoi hin ra chn trang Symbology. Ngoi cc phng php hin th d liu bng k hiu (Symbology) trn, bn cn c th to nhn (label) bng ch cho cc i tng theo 1 hay nhiu thuc tnh ca chng. V d nh vit tn ca cch a danh hay hin th din tch ca chng... to label cho mt layer no hy chut phi vo tn ca layer trong TOC ri chn thc n Properties. Trong hp thoi hin ra chn trang Labels.

Bi tpTrong bi tp ny chng ta s thc tp cch hin th mt bn hnh chnh khu vc ng Nam . Tt c cc d liu c cho trong th mc C:\ArcGIS_course\SouthEastAsia. Bc 1. To bn v thm d liu Chy ArcMap ri to mt bn mi. Bm nt Add Data ri thm tt c 6 shapefile thc mc C:\GIS_course\SouthEastAsia

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i tn ca Data Frame t "Layer1" thnh "Single Symbol" bng cch: bm chut 2 ln chm (bm chm ch khng bm nhanh) ri g "Single Symbol", bm Enter. Sp xp th t cc layer trong TOC theo th t t trn xung di nh sau: Cities, Admin_line, Rivers, Water_polys, Admin_polys, Countries.

Trn mn hnh s hin ra hp thoi Symbol Selector (hnh di). Chn kiu k hiu c sn l "Circle 2". Bm vo nt Color t mu cho k hiu l mu vng (c tn l Autunite Yellow). t Size l 8 pixel cho kch thc ca k hiu Bm nt OK, bn s quay v hp thoi Layer Properties, bm tip nt OK ln na ng hp thoi ny. Hy xem cch hin th cc thnh ph trong ca s ArcMap v k hiu di dng "Cities" trong TOC.

Bc 2. To thm mt Data Frame v chuyn lp Admin_polys vo Vo thc n Insert Data Frame thm mt Data Frame mi. i tn Data Frame mi thnh "Graduated Color" Dng chut ko layer "Admin_polys" trong TOC xung pha di Data Frame "Graduated Color", lp ny s c chuyn v Data Frame "Graduated Color"

Tip sau y chng ta s t ch hin th cho cc lp Data Frame "Single Symbol". thi im ny trn mn hnh ch hin th Data Frame "Graduated Color" vi lp duy nht l "Admin_polys" (do n ang l Active Data Frame). chuyn sang Data Frame "Single Symbol", hy bm chut phi vo n trong TOC ri chn thc n Activate.Bc 3. t ch hin th (Symbology) cho layer "Cities" Bm chut phi vo "Cities" trong TOC ri chn Properties, trong hp thoi hin ra vo trang Symbology. Trong Show chn Features ri chn phng php hin th l Single Symbol (xem hnh di). Bm vo nt Symbol

26


Bc 4. t ch hin th cho lp Admin_line.

Trong lp Admin_line c ng ranh gii hnh chnh bao gm cc loi: ng b bin (Coastline), ranh gii quc gia (International Boundary), ng bao quanh cc o (reef), ranh gii vng v li ta . Loi ng c cho trong thuc tnh BND_Type ca lp Admin_line. Trong bc ny chng ta ch hin th ng b bin (Coastline) v ranh gii quc gia (International Boundary). Vo ca s Properties ca lp Admin_line, bm vo trang Symbology (tham kho bc 3). Chn phng php l Categories ri Unique Values Chn Value Field (thuc tnh lm c s hin th) l BND_Type Bm nt Add All Values, ArcMap s tm tt c cc gi tr ca BND_Type trong bng thuc tnh v gn cho mi gi tr mt mu.

"Coastline", mu l "Ultra Blue", Width (lc nt) l 1. Bm OK ng hp thoi Symbol Selector. t k hiu cho ng ranh gii quc gia (Int. Bnd) bng cch nhy p chut vo ng k hiu ca n (hnh trn), trong hp thoi Symbol Selector hin ra chn kiu ng l "Boundary, County". Tuy nhin kiu ng c sn ny khng hon ton ging nh chng ta mong mun. Ta c th chnh sa n bng cc thao tc tip sau: Trong hp thoi Symbol Selector bm vo nt Properties, trn mn hnh s hin ra hp thoi Symbol Property Editor cho php chng ta sa hoc to ra k hiu mi (xem hnh di). Trong Layers ca hp thoi Symbol Property Editor ta thy ng ca chng ta hin nay gm 2 phn: 1 ng nt t trn v ng nn mu xm di. Hy bm chut vo ng nt t chn n. Trong trang Cartographic Line hy t Width (lc nt) bng 0,24 Bm vo trang Template (hnh di). Hy dng chut ko vung nh mu xm sang pha bn phi ri bm chut vo cc vung nh to ra c kiu ng nh trong hnh v sau (ch phn trong hnh ellipse, mi khi bn bm chut vo vung nh n s i mu):

Do mc ch ca chng ta ch hin th ng Coastline v Int. Bnd, cc loi ng khc khng hin th nn xa chng khi danh sch bng cch: nhn nt Ctrl trn bn phm, ln lt bm chut vo cc kiu ng Gridline v Reef ri bm nt Remove. Sau trng (uncheck) vung Symbol dng (xem hnh trn) t k hiu cho Coastline bng cch nhy p chut vo ng k hiu ca n (hnh trn), trong hp thoi Symbol Selector hin ra chn kiu ng l

Bm nt OK 3 ln ln lt ng cc hp thoi Symbol Property Editor, Symbol Selector v Layer Properties. Hy quan st cch th hin ng ranh gii trn mn hnh v cc k hiu pha di Layer Admin_line trong TOC.

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Bc 5. t k hiu cho lp River Hy lm tng t nh bc 3 v 4, chn k hiu c sn l "River"

vo nt Outline ri chn mu ca ng bao cng l "Big Sky Blue". Bm nt OK 2 ln ln lt ng cc hp thoi Symbol Property Editor, Symbol Selector.

Bc 6. t k hiu cho lp Water Polys

Lp Water Polys cha cc i tng thy vn dng vng (ch rng lp River cha cc sng nhng dng ng). Bc ny chng ta lm tng t nh bc 4. y chng ta cng ch hin th 3 loi i tng l Lake, Intermittent lake (h khng c nc quanh nm) v River. Loi i tng c cho trong thuc tnh WATER_TYPE. M ca s Properties ca Water Polys, vo trang General, trong Layer Name i tn n thnh Water Features. Vo trang Symbology, chn phng php hin th l Categories Unique Values. Chn Value Field l WATER_TYPE. Bm nt Add All Values, sau xa tt c cc i tng Reservoir (h gi nc nhn to) b du (uncheck) (tham kho thm bc 4) t k hiu cho Lake kiu c sn "Lake" t k hiu cho River l kiu c sn "Jade" vi mu Outline l "Delft Blue" Bm OK ng hp thoi Layer Properties.

Bc 7. t k hiu cho lp Countries.

Lp Countries s c hin th bng mt mu duy nht khng c ng bao (do ranh gii quc gia t trong Admin_line). Vo Layer Properties ca lp Countries, trang Symbology. Chn phng php hin th l Features Single Symbol, bm vo nt Symbol ri chn mu l "Yucca Yellow", Outline Color l "No Color" (khng v ng bao). Bm OK nhiu ln ng cc hp thoi trn mn hnh.

t k hiu cho Intermittent lake bng cch nhy p vo k hiu ca n. Trong hp thoi hin ra chn k hiu c sn l "10% Ordered Stipple". K hiu ny khng hon ton ph hp nn ta li tip tc thay i n. Bm vo nt Properties, trong hp thoi Symbol Property Editor hin ra vo trang Picture Fill (hnh di) ri t Foreground Color l "Big Sky Blue", Scale X = 1,50, Scale Y = 1,50. Bm

Bc 8. Thm mu nn cho Data Frame "Single Symbol" Trong TOC bm chut phi vo Data Frame "Single Symbol" ri chn thc n Properties. Vo trang "Frame", trong Background chn kiu l LtBlue.

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Bm OK ng hp thoi.

Bc 9.

Bc 9. To nhn (label) cho cc lp "Cities" v "Countries"

Vo hp thoi Properties ca lp Cities, trang Labels (hnh di). nh du Label features in this layer Trong Label Field chn "NAME" l thuc tnh cha tn ca thnh ph. Bm vo nt Symbol ri chn ch l Arial, c 8, bm nt OK Bm OK ng hp thoi Layer Properties.

Bc 10. Phn loi v hin th cc khu vc hnh chnh theo mt dn c Lm tng t i vi lp "Countries" song chn trng l CNTRY_NAME, c ch l 10, Bold. Ngoi ra bn hy bm vo nt Label Placement Options ri trong hp thoi hin ra chn Remove Dublicate labels (mi i tng ch to 1 nhn, nu khng th vi Philippines l nc c nhiu o s hin ra nhiu nhn). Hy phng to khu vc ng Nam v t l 1:15.000.000 gn ging hnh v sau:

Chng ta s s dng cc thng tin v dn s v din tch c trong thuc tnh POP_ADMIN v SQKM_ADM ca lp Admin_polys tnh mt v hin th cc khu vc hnh chnh bng cc mu khc nhau. Hy lm cho Data Frame "Graduated Symbol" tr thnh Active (tham kho phn cui ca bc 2). M bng thuc tnh ca lp Admin_Polys v nghin cu cc gi tr ca trng POP_ADMIN (dn s), ta thy mt s vng c gi tr m (-99999), c ngha l nhng vng khng c d liu. Sau ny chng ta s hin th nhng vng ny bng mu xm. ng bng thuc tnh. Vo hp thoi Layer Properties ca lp Admin_Polys, trang Symbology (hnh di). t phng php l Quantities Graduated Color Chn Value Field l POP_ADMIN

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Chn Normalization l SQKM_ADMIN, ArcMap s tnh gi tr (POP_ADMIN/SQKM_ADMIN) ri s dng n lm ch tiu hin th. Trong Color Ramp chn di mu t vng (yellow) n xanh nc bin (blue) hin th. Do mt dn s l gi tr lin tc nn trong bc sau ta phi t cch chia khong cho hp l (hin nay ArcMap ang t ng chia thnh 5 khong - 5 classes). Ngoi ra, ta cng phi loi b cc gi tr < 0 (khng c d liu). Trong classes t gi tr bng 8 khong.

Bc 11. To nhn cho lp Admin_polys theo mt dn c

Do lp Admin_polys khng c thuc tnh "mt dn c" m ch c "POP_ADMIN" v "SQKM_ADMIN" (xem phn trn) nn khi to nhn ta phi dng biu thc tnh mt dn c. Bm vo nt Classify, trong hp thoi Classification hin ra bm vo nt Exclusion (loi b) Trong hp thoi Data Exclusion hin ra hy vo trang Query (hnh di). Hy nhp dng iu kin sau (loi b cc vng c dn s , = v . V d nh lnh sau s chn tt c cc vng 2 c din tch ln hn hoc bng 1500m : AREA >= 1500 Bn c th thc hin cc php tnh ton trong cc biu thc. Cc php ton bao 2 gm + - * v /. V d tm cc nc c mt dn c nh hn 25 ngi /m bn c th s dng lnh sau: POP2000 / Area TAX + PRICE * "AREA" kim sot th t ca cc php ton bn c th s dng cc du ngoc, v d nh: NETVALUE > (TAX + PRICE) * AREA tm nhiu dng hay nhiu gi tr hy s dng lnh IN: CNTRY_NAME IN (Vietnam, India, Thailand, China) ra cc iu kin phc tp hy s dng cc lnh AND, OR v NOT, v d: CITY_NAME = Hanoi AND WARD_POP < 10000 HIEN_TRANG = 60 OR DIEN_TICH >= 200 CITY_NAME = Hanoi AND NOT DISTRICT_NAME" = ThanhXuan Ngoi phng php chn i tng bng lnh truy vn Query, bn c th s dng phng php chn bng tay. Hy chn cng c Select Features ri bm vo cc i tng cn chn. C 4 ch chn i tng khi bn s dng phng php ny. m t tng ch hy hnh dung bn chn 2 i tng l A v B, khi : - Create new selection: nu bm vo C th C s c chn, A v B khng c chn na. - Add to current selection: nu bm vo C th c A, B v C s c chn. - Remove from current selection: Nu bn bm vo A th ch c B tip tc c chn. - Select from current selection: Nu bn bm vo A th ch c A tip tc c chn.

Dng lnh truy vn khai thc d liu t cc bng. Hin th kt qu truy vn To lin kt (hyperlink) Tnh ton s liu thng k t cc bng

Kin thc nnBn trong ArcGIS cha ng mt khi lng ln thng tin. Tuy nhin, bn khng tr nn qu phc tp kh s dng, khng phi tt c cc thng tin ny c th hin trc quan trn bn , nhiu thng tin khc tuy nm trong c s d liu nhng khng c hin th nh cc thuc tnh khng phi l trng tm ca cc i tng, mi lin h logic gia cc i tng,... ArcGIS c mt s cng c khai thc cc thng tin : cng c Identify tr li cu hi " l ci g?", cng c Query tm cc i tng tha mn mt hay nhiu iu kin no hay phn tch d liu. Trong bi ny chng ta s s dng query lm vic vi cc bng thuc tnh. Cn vic s dng chng pht hin cc mi lin kt khng gian v phn tch khng gian s c nghin cu trong cc bi sau. Mt lnh truy vn n gin bao gm tn trng, ton t v gi tr. Cc lnh truy vn n gin c th kt hp vi nhau to thnh cc lnh phc tp. V d v lnh truy vn (query) c vit bng ngn ng SQL: SELECT * FROM CITIES WHERE "POP" > 100000 (c ngha l: chn tt c cc thnh ph c s dn c (trng POP) ln hn 100000 t bng CITIES). Ty thuc vo nh dng ca d liu m bn nh khai thc bng lnh truy vn, cch vit tn ca cc trng (field) s khc nhau. i vi ArcInfo coverages, shapefiles, INFO table hay dBase table tn ca cc trng phi c a vo du ngoc kp, v d nh: "POP", cn i vi Geodatabase th phi a vo du ngoc vung: [POP]. i vi shared database th ch cn vit n gin l POP. Cc d liu dng ch (text, string) th cn phi a vo du ngoc n, v d nh: "City_Name"='Hanoi'. Cc d liu dng ch phn bit ch hoa v ch thng (case sensitive). Khi bn khng chc lm v ni dng d liu dng ch th c th dng lnh LIKE, v d: "City_Name" LIKE 'hanoi'.

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Cc i tng c chn s c mu xanh da tri. Bn c th thay i mu mc nh ny trong thc n Selection Option. Nu mun, bn c th ghi cc i tng c chn thnh mt layer mi hay xut d liu (export) thnh mt Shapefile khc. Trong bng thuc tnh bn c th ch hin th cc i tng c chn. lm c iu hy bm vo nt Selected nh hnh v di y:

Nhy p vo CITY_NAME a trng ny vo trong lnh truy vn. Bm vo nt c du ' = ' n hin th sau t CITY_NAME Trong danh sch Unique sample values tm Hanoi ri nhy p n hin th ng sau du =. Nh vy ta s c lnh truy vn vit bng ngn ng SQL nh sau: SELECT * FROM Cities WHERE "CITY_NAME" = 'Hanoi'

S th t ca dng

Bi tpBc 1. To mi bn v thm d liu To mi mt bn Thm cc lp Admin, Countries v Cities t th mc C:\ArcGIS_course\DCW\ Thay i th t ca cc lp Cities hin th ln trn cc lp khc Bm nt Apply Dich chuyn ca s bng thuc tnh c th nhn r H Ni trn bn . Hy kim tra xem c ng thnh ph c chn l H Ni hay khng? Ch : thay v 3 thao tc u tin, bn c th s dng thc n Selection Select by Attributes m hp thoi Select By Attributes. Khi , trong layer cn t tn lp mnh mun truy vn.

Bc 2. To mt lnh truy vn n gin tm thnh ph H Ni Bn s to mt lnh truy vn n gin chn i tng m t thnh ph H Ni trong lp Cities. M bng thuc tnh ca lp Cities Bm vo nt Options Chn Select by Attributes, hp thoi Select by Attributes s hin ra (hnh di). Trong danh sch cc trng (Fields) tm CITY_NAME ri bm vo . rng ArcMap s t ng to ra danh sch Unique Sample Values ( pha bn phi hp thoi) theo cc s liu c trong trng CITY_NAME

Bc 3. To lnh truy vn tm tt c cc thnh ph c tn bt u bng ch H M hp thoi Select by Attributes cho lp Cities (tham kho bc trn). Trong hp thoi hin ra hy to lnh truy vn nh sau:

45


SELECT * FROM Cities WHERE "CITY_NAME" Like 'H%' Bm nt Apply M bng thuc tnh ca Cities ri kim tra xem c ng tt c cc thnh ph c tn bt u bng ch H c chn hay khng.

Bc 4. Vit lnh truy vn tm cc thnh ph ca Vit Nam c dn s ln hn 100 000 v t hn 1 triu ngi. M bng thuc tnh ca lp Cities nu n cha m. Ta s thy bng thuc tnh c cha thng tin v dn s trng POP_CLASS song cc thng tin c lu di dng khong v d liu khng phi dng s (number) m l dng ch (text). V d nh "50.000 to 100.000". Do bn khng th dng cc php ton so snh n gin t lnh truy vn c. Tuy nhin, hy rng c trong bng cn c trng POP_RANK sp xp cc thnh ph theo s dn c cho trong POP_CLASS. Chng ta s s dng trng ny tm kim. Bm vo tn trng POP_RANK trong bng thuc tnh. Chn thc n Sort Ascending Hy xem trong bng th gi tr no ca POP_RANK tng ng vi cc thnh ph c dn s ln hn 100.000 ? p s: 5 V gi tr no ca POP_RANK tng ng vi cc thnh ph c dn s t hn 1.000.000? p s: 3

Bc 5. Thu thp cc s liu thng k

Bn c th thu thp nhanh chng s liu thng k v cc trng cha d liu dng s trong bng thuc tnh. Sau y chng ta s th thu thp s liu thng k v cc nc ng Nam : ng bng thuc tnh ca Cities ri m bng thuc tnh ca Countries. Bm chut phi vo tn trng "Area" ri chn Statistics trong thc n hin ra. Trn mn hnh s hin th ra ca s thng k ca trng "Area":

Chng ta s s dng 2 gi tr va tm c trn chn ra cc thnh ph ca Vit Nam c dn s t 100.000 n 1.000.000. Trong bng thuc tnh ca Cities, bm vo nt Options ri chn Select by Attributes. Trong hp thoi Select by Attributes hin ra (hnh di), bm nt Clear xa lnh truy vn va to bc trc. Nhy p vo tn trng "POP_RANK thm n vo ca s lnh truy vn. Dng cc nt trong hp thoi hay g bng tay lnh truy vn sau: Bm nt Apply thc hin lnh truy vn. Hy kim tra li trong bng thuc tnh (hay trn bn ) xem cc thnh ph no c chn.

"POP_RANK" >= 3 AND "POP_RANK"

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