Name

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  fn_hg3

Purpose

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  Evaluate the 3-parameter Henyey-Greenstein phase function.

Description

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Category

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  Mathematical

Calling Sequence

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  fn_hg3, g, a, F, /radians

Inputs

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    g: Phase angle(s) in degrees.
    a: Array of parameters:
        A[0] = forward asymmetry (should be positive)
        A[1] = backward asymmetry (should be negative)
        A[2] = forward fraction (between 0 and 1)

Optional Input Parameters

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Keyword Input Parameters

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    radians: Phase angle is in radians instead of default degrees.

Outputs

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    F: The value of the function at each g.

Keyword Output Parameters

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Optional Output Parameters

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Common Blocks

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  None.

Side Effects

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  None.

Restrictions

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  None.

Procedure

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Modification History

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  1999-Nov-13 Created by Will Grundy
  2001-Oct-29 WMG added radians keyword