ES 551 XA/ZA

Instructions for Tutorial Exercises
Idrisi for Windows (ver. 2)

All Idrisi tutorial files are stored in the c:\exercise or c:\exerwin directories (geospatial analysis laboratory, on campus). Students should copy "necessary" files into their personal work directory--do NOT attempt to work in the exercise (or exerwin) directories, unless instructed to do so. These exercises demonstrate some capabilities of Idrisi for Windows. Page numbers refer to the printed version of the tutorials (on campus); CD versions may be different.

Note: These instructions are designed specifically for Idrisi for Windows (ver. 2). New Idrisi32 tutorials are similar in some respects, but differ in many ways. The tutorial numbering scheme is altered, and several new exercises are contained in the Idrisi32 tutorials. The equivalent Idrisi32 tutorials are indicated in parentheses below.

Tutorials 1-2 (Idrisi32 1-1 to 1-3)

Work in c:\exercise directory, through page 13-14.

Necessary files: RELIEF.* NJOLODEM.* NJOLOFC.* Copy these files into your personal working folder, beginning on p. 13-15.

Turn in

Note: Students may turn in files via e-mail. Use the "Map Composer" to save your images as bitmap (BMP) files, which can be attached to e-mail messages. To reduce file size, you can convert BMP files to GIF or JPEG format (optional).

3. Map Composition (Idrisi32 1-4)

This is a basic exercise in building a map display from existing components--various datasets, palettes, etc. The exercise demonstrates the features that one expects to find on a complete map--title, legend, map image, scale bar, north arrow, and explanation. Attractive map composition is the key for effective visual display of geospatial information.


Notes: Refer to lettered sections in tutorial.

a) Use an expansion factor of 1 for display of WESTBORO.

b) Large vector files can take some time to display, especially on older computers. After adding WESTLULC, turn it "off" in Composer, if you wish to speed up display. Click WESTBORO to red in Composer, and switch to manual mode to stop immediate implementation of changes. You will need to click on "Redraw" to activate future changes.

d) Add your name to the end of the title; you may have to resize (reduce font) and reposition it.

f) After adding WESTRDS and WESTRDS2, turn them off in Composer, if you wish to speed up display.

g) When finished with map composition, click all layers "on" in Composer for complete display.

h) On-campus students, make a paper copy of WESTMAP on the HP DeskJet 660C printer. Click on "Print Composition" in Composer and make a portrait printout. Printing will take about 3-4 minutes. You may find the printer does some unexpected things with your map composition. Distance-learning students save a digital (bmp) file of your map composition.

Notice the scale bar and units of measurement that are displayed on your map composition. Examine the documentation files for several of the input datasets and note the "reference units" for each.

1. What reference units are employed for the input datasets for Westboro?

2. Can you explain why the reference units are not the same for each dataset?

Turn in

4. Palettes, Symbols and Scaling (Idrisi32 1-5)

For this exercise, you will explore further capabilities for creating map compositions, placing symbols/captions, and improving the overall appearance of images.

Necessary files: ETDEM.* ETPROV.* BRAZIL2.*

Notes: Refer to sections in tutorial.

After question 2. Add your name to title of ETDEM; resize and center title. Save your final ETDEM map composition, and make a BMP file to turn in.

s) Enter an appropriate title for LINEAR, and indicate "linear stretch" for value units.

t) Enter an appropriate title for SAT, and indicate "2.5% saturation" for value units.

Turn in

5. Database Query (Idrisi32 2-2)

In this exercise, you will begin to learn of the power of GIS to manipulate data and create solutions for questions based on various kinds of geographic data inputs. Before beginning the exercise, students should read the section on Introduction to Cartographic Modeling (p. 13-28/29; Idrisi32 2-1). See also textbook chap. 13, section on model flowcharting (p. 371-384).

Necessary files: DRELIEF.* DSOILS.*


Before you begin, update DRELIEF documentation file. Add "elev. meters" for value units.

Also update DSOILS documentation file. Select "plane" for the reference system.

After finishing the tutorial, you should prepare a map composition complete with title (incl. your name), legend, scale bar, and grid arrow. Notice that PLOTS2 has some "empty" legend categories--only classes 0, 1, 3 and 8 contain data. In order to create a simple legend, you should reclassify the image as follows.

3 => 2
8 => 3
(other classes remain unchanged).

Create a special color palette, in which the background (0) appears light gray, and the sorghum plots (1-3) are different shades of green and yellow. Remember to provide a label for each legend entry. Name your composition SORGHUM. Make a paper print (or digital file) to turn in.

Turn in

6. Map Algebra (Idrisi32 2-6)

As the name suggests, this exercise involves algebraic calculations of geographic data. Climatic and topographic variables are cross-classified in order to delineate suitable agricultural zones.

Necessary files: NRAIN.* NRELIEF.*

Notes: Refer to sections in tutorial.

j) After running Crosstab, print out (or save) the tabular results. Click printer button on right side of display window.

k) Turn in written answer for Figure 2.

After completing the tutorial, create a map composition of ACZONES with title (incl. your name), legend, scale bar, and grid arrow. Make print out (or digital file) to turn in.

Turn in

7. Database Workshop (not in Idrisi32)

In this exercise GIS is combined with a database management system (DBMS). This allows the database to be analyzed in geographic context. In this example, animal production is analyzed for its impact on emission of methane, a greenhouse gas.


Notes: Refer to sections in tutorial.

a) Compare the AWAJAS display with your earlier map composition of Ethiopia (ETDEM).

o) Bring up the display of cattle population in Ethiopian awrajas. Use the map composer to add an appropriate title (incl. your name) and date. Do not add legend, scale bar, or grid arrow. Name this map composition CATTLE, and save it to turn in (paper print or digital file).

v) Compare the TEMPSURF display with your earlier map composition of Ethiopia (ETDEM).

z) Use the map composer to add an appropriate title (incl. your name) and date. Do not add legend, scale bar, or grid arrow. Name this map composition METHANE, and save it to turn in (paper print or digital file).

Additional questions:
5. Are the CATTLE and METHANE displays similar? Are they identical? Explain your answers.

6. On the basis of this exercise, which animals appear to contribute the most to methane production in Ethiopia? Explain the evidence for your conclusions.

Turn in

8. Distance and Context Operators (Idrisi32 2-3 and 2-5)

Among the most important applications of GIS is site selection. This involves identifying "suitable" sites based on combinations of conditions, such as topography, soils, vegetation cover, geology, water resources, access to transportation, distance from markets, risk factors, and other considerations. For this exercise, a suitable site will be determined for industrial development.

Necessary files: RELIEF.* LANDUSE.*

Notes: Refer to sections in tutorial.

a) To make the ORTHO display, click on title and legend, and choose output resolution of 640 x 480.

m) Hint: use Group, Area, and Reclass modules, in order to make the SUITABLE image. When displaying your "grouped" file, choose the Qualitative 256 palette for good visual depiction. Choose tabular output for Area module.

After completing SUITABLE, you should have one area that meets all the criteria for the new manufacturing plant. Make a special palette that shows the suitable area in bright orange and the background in olive-green. Finally create a map composition with the usual components--scale bar, title, legend, grid arrow. Make a paper print or digital file to turn in.

Turn in

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ES 551 © J.S. Aber (2000).