Below are detailed instructions for how to use ArcGIS collector on an iPad in offline mode to collect field data on a grid of determined cell size (20x20m) overlaid on a base map of high resolution imagery. Forms are set up to have drop down menus and time stamps are automatically recorded.
The main steps are:
- Create the grid as a matrix of rectangular polygons and save it as a shape file.
- Edit the attribute table of the shape file to contain the appropriate fields for entry, including codes and drop downs.
- Create an online web map with the to hold the data
- Download the web map to the iPad, configure and enter data, then sync.
Details are outlined in this pdf.
In trying to get a grip on the newly released Shiny library for R I simply rewrote the example from the tutorial to work with ggplot. The code is taken from the Shiny Tutorial.
I did not make any changes to ui.R provided in the tutorial. The rewritten server.R is below.
Using my rudimentary knowledge of Python, I was interested in exploring the use of rpy2 to eventually be able to bring together spatial data analysis done in Python, with some higher level tools in R – in this case the powerful graphics library ggplot2 to visualize the results.
My setup is Mac OS 10.7.3, Python 2.7, R 2.14. (R needs to be compiled with ‘–enable-R-shlib’, which the official CRAN binary for Mac is). Also required are Xcode and NumPy.
There is no binary for rpy2 for my configuration available, so I downloaded the source (2.2.3). Extract somewhere, change into the rpy2-2.2.3 directory and install with:
sudo python setup.py build install
The Python code below takes a csv file (output from a some prior geoprocessing done with ArcPy) and produces a graphic with a map and a scatterplot – see the comments for further details.
Data can be downloaded here.