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 Scanning Multidimensional Arrays
 ================================
 
    There is no special `for' statement for scanning a
 "multidimensional" array. There cannot be one, because, in truth, there
 are no multidimensional arrays or elements--there is only a
 multidimensional _way of accessing_ an array.
 
    However, if your program has an array that is always accessed as
 multidimensional, you can get the effect of scanning it by combining
DONTPRINTYET  the scanning `for' statement ( Scanning All Elements of an Array
 Scanning an Array.) with the built-in `split' function (*note String
DONTPRINTYET  the scanning `for' statement ( Scanning All Elements of an Array
 Scanning an Array.) with the built-in `split' function ( String

 Manipulation Functions String Functions.).  It works in the following
 manner:
 
      for (combined in array) {
          split(combined, separate, SUBSEP)
          ...
      }
 
 This sets the variable `combined' to each concatenated combined index
 in the array, and splits it into the individual indices by breaking it
 apart where the value of `SUBSEP' appears.  The individual indices then
 become the elements of the array `separate'.
 
    Thus, if a value is previously stored in `array[1, "foo"]'; then an
 element with index `"1\034foo"' exists in `array'.  (Recall that the
 default value of `SUBSEP' is the character with code 034.)  Sooner or
 later, the `for' statement finds that index and does an iteration with
 the variable `combined' set to `"1\034foo"'.  Then the `split' function
 is called as follows:
 
      split("1\034foo", separate, "\034")
 
 The result is to set `separate[1]' to `"1"' and `separate[2]' to
 `"foo"'.  Presto! The original sequence of separate indices is
 recovered.
 

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(gawk.info.gz) Multi-dimensional

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