Need help on a Matlab command? help nameofcommand will get you text-y help right there on the command line; doc nameofcommand will bring up the more graphical help browser. (You can also generally Google something like Matlab nameofcommand and get the Mathworks documentation in your web browser as well.)
Numeric output too short (not enough digits)? Use the format command (e.g. format long g will display numbers in a longer format; use format short to go back to the default shorter format with fewer digits)