Name

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meanerr2

Purpose (one Line)

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Calculate the mean and estimated error for a set of weighted data points

Description

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This routine is adapted from Program 5-1, XFIT, from "Data Reduction
and Error Analysis for the Physical Sciences", p. 76, by Philip R.
Bevington, McGraw Hill. This routine computes the weighted mean using
Instrumental weights (w=1/sigma^2). The final uncertainty is
insensitive to a multiplicative constant on the weights.

Category

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Statistics

Calling Sequence

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meanerr2,x,weight,xmean,xsigma

Inputs

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x - Array of data points
weight - array of weights for data points

Optional Input Parameters

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None.

Keyword Parameters

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None.

Outputs

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xmean - weighted mean
xsigma - uncertainty of xmean

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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Written by Marc W. Buie, Lowell Observatory, 2000/10/01
  2000/10/3, MWB, mostly WMG, it now works.