March 28, 2018

agenda

  • what is a GIS
  • software available
  • GIS file types
  • how to model earth
  • getting GIS data into R
  • querying GIS data

what is a GIS: Geograpahic Information System

  • capture, store, display, and analyze positional data …
  • data capture — can be more adequate than MS Access, REDCap etc.
  • store — as simple as a flat csv file or as complex as multi-dimensional relational database
  • display — allows us to layer on graphics similar to Adobe Photoshop
  • analyze — various querying, descriptive statistics, and inferential statistics functions

softwares vary in capacity to capture, store, display, and analyze

softwares may also vary in capacity

  • static visualization: Esri & R> GeoDa & Python
  • dynamic visualization: D3 & R & Esri > all others
  • inferential statistics: R & GeoDa > Esri & D3
  • plan out workflow
    • folder & file management
    • version control
      • e.g., datestamps, analyst initials

file management: GeoDa & Esri

file management: R & Esri

  • for this presentation please create parent folder and middle 3 child folders

spatial data management

spatial data management

comparisson of spatial data formats

usage shapefile feature class geojson
advanced Esri processing some all* all
parent container folder file geodatabase folder
write access cross-plaform Esri only cross-plaform
read access cross-plaform cross-plaform cross-plaform

*e.g., store geometric networks, terrains, dynamically update geometry, etc.

how to model earth: coordinate systems

spherical coordinate system

spherical coordinate system

projected coordinate system

projected coordinate system

how to model earth: spherical coordinate systems