This is the DEM file packer from Ian Parberry, "Tobler's First Law of Geography, Self Similarity, and Perlin Noise: A Large Scale Analysis of Gradient Distribution in Southern Utah with Application to Procedural Terrain Generation". You will need to download the DEM files listed in filelist20x20.txt from the UARGRC before running it. This program outputs a packed elevation data file called UtahDEMData.bin which you should move to the Analyze folder before running the Terrain Gradient Analyzer.

Don't execute this program unless you have at least 16GB of RAM (preferably 32GB). A solid state hard drive is also recommended. Otherwise it may take a very, very long time to run instead of just a long time. On a good day on a fairly recent PC that has nothing much else to do at the same time, running downhill with a tail wind, assuming that the gods are with you and your karma is good and that your computer, in its infinite wisdom, doesn't decide on a whim that it must install 128 important updates and and shut down NOW, then it should take between 30 and 45 minutes to run. Otherwise your guess is as good as mine. This program does report various interesting things to the console so you can reassure yourself that it is actually working and not just hanging around hogging system resources.

If you are thinking about trying it out on a single file before going Whole Hog, just uncomment out the #define TESTRUN and provide a file named filelisttestrun.txt with the name of a single DEM file in it.