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*** Notes & Errata (Oct 2012) ***

Introduction to GIS Using Open Source SoftwareAugust 2012 (3rd edition)Frank Donnelly, Baruch College CUNY

* Symbolization and Color Ramps

This effects section 3.3 Step 7 (page 36) and section 4.4 Step 2 (page 68).

In previous versions of QGIS the default color ramps for displaying graduated values were limited to a few options, and these options defied conventional practice because the color schemes went from dark to light for low to high values (standard practice is light to dark colors for low to high values).

The suggested course of action to overcome this was to ignore the defaults and add a custom Color Brewer scheme. However, with QGIS 1.8 the default color rampswere expanded and corrected to follow conventional practice, and the tutorial was not updated to reflect this. The steps for adding a custom Color Brewer schemestill apply, but are not absolutely necessary as the defaults are sufficient.

If you are using MS Windows and had a previous version of QGIS installed (priorto 1.8), you have to uninstall the previous version AND delete the QGIS settingsfolder that is created under C:\users\your username before installing the lates

t version in order for the color ramp change to take effect. By removing this folder, you are also deleting your preferences for plugins, and will have to add and customize them again once you install the new version.

* QGIS 1.80 Data Browser for Macs

This effects section 3.8 (page 50).

For Mac users, the icon to launch the new stand-alone Data Browser for QGIS 1.80isn't obvious to find. The application appears under QGIS.app/Contents/MacOS/bin. You will need to create a symlink or Finder alias to make it easier to launch. A better approach will be implemented in a future release.

* Excel Support

The tabular file formats that are officially supported by QGIS are DBF (Section3.3 pages 38-39) and CSV (Section 4.2 pages 63-64).

Although not officially supported, tests have shown that older Excel files (.xls) can also be added to QGIS 1.8 in order to join them to shapefiles or other features. Add the file using the add vector button, under the filter select all files, then select your spreadsheet. If the Excel workbook has multiple sheets youare prompted to select one. Details are available here:

http://www.qgis.nl/2012/07/17/direct-gebruiken-van-data-uit-excel-bestand/?lang=en

It is unclear if support will become official in a future version, but it seemsreasonable to expect.

* USC Geocoding Services

This effects Section 3.4.2 (page 41) and 5.1 (page 86).

The University of Southern California's GIS lab was mentioned as a resource forgeocoding addresses - assigning latitude and longitude coordinate to address-bas

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ed data so that it can be plotted in GIS. In October 2012 these services moved and are now housed at Texas A&M University at http://geoservices.tamu.edu/.