ReplaceAll (/.)
 Usage
Notes
 Further Examples
ReplaceAll replaces once at all levels of the expression.
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This is the same command written with the slash-dot notation.
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Replace applies only to the whole expression.
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This replaces a by b first. Then there are two b's that get replaced by d.
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By contrast, this replaces a by b and b by d at one time.
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ReplaceAll applies the set of rules exactly once on each part of the expression.
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ReplaceRepeated uses ReplaceAll repeatedly until the expression stops changing.
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Here is the same command written with the slash-slash-dot notation.
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This constructs a list of replacements from two lists.
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This applies the rules.
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This rule replaces expressions whose heads are Integer, Rational, or Plus by their logarithms.
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Using ReplaceAll, only the first prime number in this list is replaced by its cube.
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Using ReplaceRepeated, all of the prime numbers are replaced by their cubes.
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Here is an expression.
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Here subexpressions of expr with head f or g and one or more arguments are squared.
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This does the same thing.
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Here only subexpressions which are products whose factors have the form _[__] get squared.
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Here all expressions of the form _[__] that are free of Power or Times get squared.
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Here a rule is applied repeatedly subject to the given conditions. The rule extracts all subexpressions of the form m p + n q as expressions with head h where m and n are integers and m = -n.
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This defines the function evaluatePatternMatches. In the held expression heldexpr, it replaces subexpressions that match the pattern patt by their evaluated counterparts.
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See also the Further Examples for Repeated.
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