Name

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    ATANH

Purpose

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    Numerically calculate the inverse of the TANH function for real
    values.

Category

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    Math:

Calling Sequence

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    Result = ATANH(X)

Inputs

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    X: Argument to atanh. May be an array.

Outputs

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    The arctanh of the argument. Note that because of the numerical inversion
    method, the results will be inaccurate for input values very near 1.

Example

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    IDL> PRINT, ATANH(TANH([0,1,2]))
          0.00000 1.00000 2.00000

Modification History

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    Written by: Jeremy Bailin
    27 Nov 2008 Released in JBIU