Name

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  MGH_TRIANGULATE_RECTANGLE

Purpose

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  This function returns a triangulation for a 2D rectangular grid.

Calling Sequence

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  Result = MGH_TRIANGULATE_RECTANGLE(dims)

Positional Parameters

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  dims (input, 2-element integer vector)
    Dimensions of the grid. Minimum value for each element is 2.

Keyword Parameters

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  POLYGONS (input, switch)
    Set this keyword to return a polygon-descriptor array as
    required by an IDLgrPolygon object. Default is to return a
    list of triangles as required by GRIDDATA.

Return Value

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  The function returns a long integer array. Dimensions are
  [4,2*(m-1)*(n-1)] if the POLYGONS keyword is set and
  [3,2*(m-1)*(n-1)] if it is not, where [m,n] are the input
  dimensions.
  PERFORMANCE:
  Approx linear with number of vertices @ 10^6 vertices per second
  on Pentium 3 800 MHz.
###########################################################################
  This software is provided subject to the following conditions:
  1. NIWA makes no representations or warranties regarding the
    accuracy of the software, the use to which the software may
    be put or the results to be obtained from the use of the
    software. Accordingly NIWA accepts no liability for any loss
    or damage (whether direct of indirect) incurred by any person
    through the use of or reliance on the software.
  2. NIWA is to be acknowledged as the original author of the
    software where the software is used or presented in any form.
###########################################################################

Modification History

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  Mark Hadfield, 2002-07:
    Written.
  Mark Hadfield, 2008-04:
    For the case of polygon-descriptor output (POLYGONS keyword set), the
    output is no longer reformed to one dimension, as this is unnecessary.