Just enter arithmetic expressions to compute the results.
ex.:  >2+3*7
       23

Supported operators are: Arithmetic: + - * / % ^ ! Logic: & | != == < <= > >= ~

Variables can be defined using the equal sign '=':
ex.:  >MyVariable=3.123
       3.123

Various standard functions are predefined and new functions can be defined:
ex.:  >MyFunction(x)=2*x+17;

You may enter matrices and vectors using brackets and use usual operators:
ex.:  >[1 2;3 4]*[5;6]
       [17;39]

The commands 'functions' and 'variables' show the current environment.
Enter 'modules' for the available modules, 'help index' for the help index.

For more information refer preferably to the user manual on your system or to
http://rascal.sourceforge.net/userdoc/