Day 2 Notes: Learning about Procedures and Functions via the PLOT procedure and the WHERE() function.
Day 3 Notes: IF...Then...Else statements; Loops (for, while, repeat); selecting elements of arrays
Day 4 Notes: Writing your own functions/procedures, multiplots. See the examples in here.
1) From any of the solar computers: tarrl@helios ~$ idlhelp
2) From within idl: IDL> ? [command]. "?" will bring up the idl help docs, and tacking a command onto the end will bring up help about that command.
3) Online IDL documentation from Goddard Space Flight Center
4) David Fanning's webpage: Coyote's Guide. Completely indispensable. Be sure to read JD Smith's Histogram Tutorial. Now read it again.
Remember, most things that you (or anyone else) want to do has already been done, probably in 100 different ways. Look at what they did, pick the best one, and then copy/paste!