MacChoro

MacChoro (pronounced MacKoro) was a computer program for choropleth mapping developed for early versions of the Apple Macintosh computer. A choropleth map shades areas, such as states or counties, to represent values and is mainly used for the mapping of statistical data. Released in 1986, MacChoro was the first computer mapping program to implement Macintosh's point-and-click user interface for the analysis and production of thematic maps. MacChoro II, released in 1988, was the first program to incorporate interaction in animated mapping.

Development

MacChoro began to be developed in the Fall of 1985 on an Apple Macintosh 512K (Fat Mac) computer with a single 400K floppy drive. The programming language was Fortran, and the code was based on a choropleth mapping program that was developed on a Digital Equipment VAX computer. It had to be re-written to incorporate the mouse, pull-down menus, and dialogs.

Data Classification

The program stressed data classification, and implemented six methods including unclassed, equal interval, quantile, natural breaks, standard deviation and user-defined. The unclassed method was limited to 16 shadings. Each of the remaining methods could be made with between 2 and 16 categories. Maps could be re-classified and displayed in a matter of seconds. The program was especially useful for comparing different methods of data classification.

Animation

An interactive animation feature was added in 1988. A second version of the program, MacChoro II, placed a series of maps into memory showing different methods of data classification, different number of classes, or different variables. Once finished, the animated series of maps could be displayed at up to 60 frames per second. A dialog controlled the speed of display and provided access to the individual frames.

gollark: I have 34Mbps up, 8Mbps down, which is not ideal but usable.
gollark: Some people don't even have a publicly routable IP.
gollark: Also CGNAT now.
gollark: Like I said, it's not really very hard to do that (at least at a small scale, making stuff run with the volume of data Facebook deals with is a different issue), the hurdles are more, er, social and possibly legal.
gollark: The average person really does not want to do anything remotely complicated with a computer, which is problematic, and it doesn't really *help* that a bunch of stuff (down to the balance of upload/download speeds available on home network connections) on the internet is set up now to encourage using big walled gardens and discourage running your own stuff.

References
  • Peterson, Michael P. (1995) Interactive and Animated Cartography. Englewood Cliffs, NJ: Prentice-Hall.
  • Peterson, Michael P. (1994) Spatial Visualization through Cartographic Animation: Theory and Practice. Proceedings of Geographic Information Systems / Land Information Systems GIS/LIS 1994, pp. 250-258.
  • Peterson, Michael P. (1993) Interactive Cartographic Animation. Cartography and Geographic Information Systems, 1993, Vol. 20, No. 1, 1993, pp. 40-44.
  • Tobler, W. (1973) "Choropleth Maps Without Class Intervals?." Geographical Analysis 3: 262-265.

[[Category:Aide Category:Data visualization software]]

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.