GEOCalculator is a program that can perform calculations on structural geological data. You will be able to perform the most common calculations, such as angles between lines or planes, planes bisecting lines or planes, lines with pitch, hade, trend or plunge and more. GEOCalculator can also perform drillhole calculations for oriented, partially oriented, and unoriented cores.
For every calculation you can modify the conventions you want to use. The program will show the generated results on the screen, but you can configure it to save them in a file on your hard drive. It also allows you to specify a file that it can use for inputting the values to perform calculations with. This program will let you show not only the generated results, it can also show the graphical charts that your inputs have generated.
The unregistered version of this program can be used for free by students and academics for teaching. It is fully functional, only the drillhole calculations and the range of values that they can enter is somewhat restricted.