Name

---

  MGH_INTERPOLATE

Purpose

---

  This function is a wrapper for the standard IDL INTERPOLATE
  function. It corrects for the anomalous way INTERPOLATE
  handles locations near the upper end of the input array, described
  by the IDL documentation as follows:
    Note - INTERPOLATE considers location points with values between
    zero and n, where n is the number of values in the input array
    P, to be valid. Location points outside this range are
    considered missing data. Location points x in the range
    n-1 <= x < n return the last data value in the array P.
  Note the final sentence. It is much more logical to treat points
  in the range n-1 < x < n as missing, and this is what
  MGH_INTERPOLATE does. Note also that the anomalous behaviour
  described in the paragraph above is actually done only in the case
  of linear interpolation, whereas bilinear interpolation acts in
  the way I consider logical.

Calling Sequence

---

  result = MGH_INTERPOLATE(p, x)
  result = MGH_INTERPOLATE(p, x, y)
  result = MGH_INTERPOLATE(p, x, y, z)

Parameters

---

  See documentation for INTERPOLATE.

Return Value

---

  The function returns a single or double precision floating point
  array with size & shape determined by the x, y & z parameters and
  the GRID keyword.
###########################################################################
  Copyright (c) 2002 NIWA:
  http://www.niwa.co.nz/
  Licensed under the MIT open source license:
  http://www.opensource.org/licenses/mit-license.php
###########################################################################

Modification History

---

  Mark Hadfield, 2002-06:
    Written.