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RewriteRule examples
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For example:

logrule := rule log(x) + log(y) == log(x*y)
   log(y) + log(x) + %C == log(x y) + %C

f := log(sin(x)) + log(x)
   log(sin(x)) + log(x)

logrule f
   log(x sin(x))


Note that you cannot write the simple form of a rule as:

rule1 := rule a*x+b == b*x+a

as this causes an infinite loop. The pattern is properly matched
but the result also properly matches and the pattern is applied
again. 


See Also:
o )show ApplyRules
o )show RewriteRule

