The following examples illustrate aspects of IDL's array syntax with one-dimensional arrays. Note that the functions 'indgen' and 'findgen' are handy ways of generating arrays of integers and reals respectively. The array indexing runs from 0 to N-1 where N is the number of elements. Multiple commands on one line are separated by &. The array 'c' is set equal to 'a' as a way of declaring it. More array syntax is mentioned in the description of plotting graphs on the main lab page.

IDL> a=findgen(10)+1. & print,a 
      1.00000      2.00000      3.00000      4.00000      5.00000      6.00000
      7.00000      8.00000      9.00000      10.0000
IDL> b=2*a & print,b
      2.00000      4.00000      6.00000      8.00000      10.0000      12.0000
      14.0000      16.0000      18.0000      20.0000
IDL> c=a & for i=0,9 do c[i]=b[i]/a[i] 
IDL> print,c
      2.00000      2.00000      2.00000      2.00000      2.00000      2.00000
      2.00000      2.00000      2.00000      2.00000

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