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  find <expr: expression> <any: arguments to expression...> - leave indices
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find <expr: expression> <any: arguments to expression...>  
where expression is true (use $x, $i and $self)
+
 
 +
- leave indices where expression is true (use $x, $i and $self)
  
 
The find method of fmat replaces an fmat with the (unwrapped) indices of the
 
The find method of fmat replaces an fmat with the (unwrapped) indices of the

Revision as of 10:42, 5 May 2009

find <expr: expression> <any: arguments to expression...>

- leave indices where expression is true (use $x, $i and $self)

The find method of fmat replaces an fmat with the (unwrapped) indices of the elements for which the given expression returned non-zero. The expression can use the arguments to the find method following the expression as $1, $2, etc., and the predefined super-local variables $x (the value of the element being tested), $i (its index), and $self (the reference to the fmat itself). Otherwise, only global definitions are visible within the expression. (The latter holds for any expression evaluation.)

Example: ($myfmat find $myexpr 1 20) with myexpr = '(($x >= $1) && ($i < $2))' finds values greater than 1 in the first 20 indices and replaces $myfmat with their indices.