I'm trying to install a package called heasoft in order to do some nuclear physics research. I can't seem to get the commands to work, even though I'm following the instructions as far as I can tell. Here is the instruction page: http://heasarc.gsfc.nasa.gov/docs/so...t/install.html

Here is how I've tried to type the commands. It's a standard pre-built binary, as I'm not advanced enough to mess with the source code.

rxs103@nucpc30:~/heasoft-6.26/x86_64-pc-linux-gnu-libc2.27/BUILD_DIR$ export HEADAS=/home/rxs103/heasoft-6.26/x86_64-pc-linux-gnu-libc2.27/BUILD_DIR
rxs103@nucpc30:~/heasoft-6.26/x86_64-pc-linux-gnu-libc2.27/BUILD_DIR$ . $HEADAS/headas-init.sh
headas-init.sh: ERROR -- cannot execute /home/rxs103/heasoft-6.26/x86_64-pc-linux-gnu-libc2.27/BUILD_DIR/BUILD_DIR/headas-setup