 | ; is the beginning of a comment. |
 | & allows to put 2 commands on the same line. |
 | $ allows to continue a command on the next line, or (when at the beginning
of the line) will send command to the shell. |
 | @ will include a file containing a list of IDL commands (bach) |
 | # and ## are matrix operators. |
 | ^ will allow you to redo a command from the history, asking you a string
to match. |
 | ! is used for the system variables: IDL>
print , !pi
|
The command and the different parameters are always separated by commas (with
or without space around):
IDL>
print , 'I do not like to print!'
IDL> print , 512. * 512. / 4.
IDL> plot,x,y
IDL>
readf,logical_unit,x1,x2,x3,x4
The affectation of a variable is done by the sign =
The function have its parameters between braces.
IDL> var1
= 5
IDL> var1 = 5. ; no warning if
var1 is already defined...
IDL> a =
cos(x)
IDL> b = cos(x^2 + y^2) *
alog(5*z^(1./3.))
IDL> plot , x , cos(x^2)
Arrays elements are referred using [ ] or ( ) -this is the old fashion-.
IDL>
tab[2,6] = 6.
Be careful of the different ways IDL pass the parameters.