This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# Do

 Doevaluates expr times. Doevaluates expr with the variable i successively taking on the values through (in steps of ). Do starts with . Douses steps di. Do uses the successive values , , .... Doevaluates expr looping over different values of j, etc. for each i.
• Do uses the standard Mathematica iteration specification.
• Unless an explicit Return is used, the value returned by Do is Null.
• Do first evaluates spec, then localizes the variable specified and successively assigns values to it, each time evaluating expr.
• Do effectively uses Block to localize values or variables.
• In Do is effectively equivalent to Do.
Print the first four squares:
n goes from to in steps of :
 Print the first four squares: n goes from to in steps of :
 Scope   (7)
Evaluate Print twice:
The step can be negative:
The values can be symbolic:
Loop over i and j, with j running up to i-1:
The body can be a procedure:
Break breaks out of Do:
Continue continues the loop, without executing the rest of the body:
Give a list of values to iterate over:
 Applications   (5)
Generate a symbolic continued fraction:
Build up a list of primes:
Alternatively use Reap and Sow:
Implement backsubstitution:
Implement LU triangular decomposition of matrices:
The selection sort algorithm:
Equivalent loops: