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    This function returns the converted tristimulus values for a
    provided CIE L*a*b* value assuming a particular illuminant,
      X = xr * Xr
      Y = yr * Yr
      Z = zr * Zr
      xr = fx^3 for fx^3 > epsilon
      xr = (116 * fx - 16) / kappa for fx^3 <= epsilon
      yr = ((L + 16) / 116 ) / kappa for L > kappa * epsilon
      yr = L / kappa for L <= kappa * epsilon
      zr = fz^3 for fz^3 > epsilon
      zr = (116 * fz - 16) / kappa for fz^3 <= epsilon
      fx = (a / 500) + fy
      fy = (L + 16) / 116
      fz = fy - (b / 200)
      epsilon = 0.008856
      kappa = 903.3
      Xr, Yr, Zr are the white reference for the specified illuminant


    Color Science.

Calling Sequence

    Result = LAB2XYZ( Lab, ILLUMINANT=illuminant )


      A 3-element vector or 3xn array of CIE L*a*b* coordinates

Keyword Parameters

      An optional keyword to describe the illuminant that should
      be used for the CIE L*a*b* to XYZ conversion
          0 - D65 (Daylight) [DEFAULT]
          1 - Illuminant A (Tungsten)
          2 - Illuminant F2 (Cool White Fluorescent)
          3 - Illuminant F11 (Narrow Band Fluorescent)
          4 - Illuminant F7 (Daylight Fluorescent)
          5 - Illuminant F8 (Daylight Fluorescent)

Return Value

    Result is either a 3-element vector or a 3xn array that contains
    the computed tristimulus values

Side Effects


Modification History

    Written by: Carl Salvaggio
    February, 2010 Original code
    April, 2012 Corrected white reference scaling error


    This source code is provided "as is" and without warranties as to performance
    or merchantability. The author and/or distributors of this source code may
    have made statements about this source code. Any such statements do not
    constitute warranties and shall not be relied on by the user in deciding
    whether to use this source code.
    This source code is provided without any express or implied warranties
    whatsoever. Because of the diversity of conditions and hardware under which
    this source code may be used, no warranty of fitness for a particular purpose
    is offered. The user is advised to test the source code thoroughly before
    relying on it. The user must assume the entire risk of using the source code.

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