Slow processing times and memory errors
Many of the Toolkit's functions for graph analysis ('Connectivity' tab) are highly demanding of computational time and RAM (see System Requirements). If you are encountering memory errors or runtimes that exceed your patience level, try an initial analysis using a smaller graph (larger hexagon size) or a more approximate solution.
Use of incorrect input file format
See
Flowchart of analysis process for correct graph format file for each function. Input of the wrong graph format file (e.g., a lgf file into shortest-path BC) will result in an error message.
Use of input layers with zero-valued habitat or cost
Although in some instances CAT functions can complete when input habitat layers contain small areas of zero habitat value (which will be treated as barriers), generally the minimum habitat value should be a low but non-zero value. No areas of zero value should be present in the cost data used in min-cost-max-flow analysis.
Use of inappropriate approximation parameters
If the probability value (described in the section
Connectivity Tab) for shortest-path and current-flow BC approximations is changed from the default value to a value that requires too large a subsample of the graph, the program may use the exact algorithm or may in some cases fail with an error message.
"Network Flow.exe" crashes
This may be caused by the issue described above (input layers with zero-valued habitat or cost). Or the 'convert decimals to integers' value may be set too high. Or the output filename given by the user (e.g., owl3nout in Tutorial Exercise 4) may have been incorrectly given a file suffix (e.g., .txt). If changing these parameters does not resolve the problem, please contact the developer.
Use in regions/locales where the decimal separator is a comma rather than a period
Although version 1.3 revises most functions to work in these regions (e.g., most of the world outside of the US and UK), there remain a couple of exceptions where this may causes errors:
1) Use of networkflow functions (e.g., min-cost flow) with either of these 2 options:
-d // maximum distance for 'bounded-distance' metrics
-f // supply fraction for min-cost-max-flow method
To resolve this, use a distance value which is an integer, and use a supply fraction of 1 (the default).
Reporting bugs
There are likely to be issues that arise due to software bugs. The output tab may provide error messages that are helpful in identifying the problem. Please post a description of any problems to the CAT discussion forum or email the developer at klamathconservation@gmail.com.
