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ReplaceAll
expr
/.
rules applies a rule or list of rules in an attempt to transform each subpart of an expression expr.
Example: x + 2 /. x -> a .
ReplaceAll looks at each part of expr, tries all the rules on it, and then goes on to the next part of expr. The first rule that applies to a particular part is used; no further rules are tried on that part, or on any of its subparts.
ReplaceAll applies a particular rule only once to an expression.
Example: x /. x -> x + 1.
See the notes on Replace for a description of how rules are applied to each part of expr.
expr
/.
rules returns expr if none of the rules apply.
See the Mathematica book: Section 2.4.1.
See also: Rule, Set, MapAll.
Further Examples
ReplaceAll replaces once at all levels of the expression.
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On the other hand, Replace applies only to the whole expression.
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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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THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT. SEE THE DOCUMENTATION CENTER FOR THE LATEST INFORMATION. | | | |
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