1Math::Expression::EvaluUasteorr:C:oOnpttriimbiuzteerdM(a3Pt)ehr:l:EDxopcruemsesnitoant:i:oEnvaluator::Optimizer(3)
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NAME

6       Math::Expression::Evaluator::Optimizer - Optimize
7       Math::Expression::Evaluator ASTs
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SYNOPSIS

10           use Math::Expression::Evaluator;
11           my $m = Math::Expression::Evaluator->new("2 + 4*f");
12           $m->optimize();
13           for (0..100){
14               print $m->val({f => $_}), "\n";
15           }
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DESCRIPTION

18       Math::Expression::Evaluator::Optimizer performs simple optimizations on
19       the abstract syntax tree from Math::Expression::Evaluator.
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21       You should not use this module directly, but interface it via
22       Math::Expression::Evaluator.
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24       The following optimizations are implemented:
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26       ·   Constant sub expressions: "variable + 3 * 4" is simplfied to
27           "variable + 12".
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29       ·   Joining of constants in mixed constant/variable expressions: "2 +
30           var + 3" is simplified to "var + 5". Works only with sums and
31           products (but internally a "2 - 3 + x" is represented as "2 + (-3)
32           + x", so it actually works with differences and divisions as well).
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34       ·   Flattening of nested sub expression: "a * (3 * b)" is flattened
35           into "a * 3 * b". Currently this is done before any other
36           optimization and not repeated.
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PERFORMANCE CONSIDERATIONS

39       "optimize()" currently takes two full loops through the AST, copying
40       and recreating it. If you execute "val()" only once, calling
41       "optimize()" is in fact a performance loss.
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43       If the expression is optimizable, and you execute it $n times, you
44       usually have a net gain over unoptimized execution if "$n > 15".
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46       Of course that value depends on the complexity of the expression, and
47       how well it can be reduced by the implemented optimizations.
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49       Your best is to always benchmark what you do. Most of the time the
50       compiled version returned by "->compiled" is much faster than the
51       optimized (and not compiled) form.
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55perl v5.30.0                      2019M-a0t7h-:2:6Expression::Evaluator::Optimizer(3)
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