NAME: meanerr PURPOSE: (one line) Calculate the mean and estimated errors for a set of data points DESCRIPTION: 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). CATEGORY: Statistics CALLING SEQUENCE: meanerr,x,sigmax,xmean,sigmam,sigmad INPUTS: x - Array of data points sigmax - array of standard deviations for data points OPTIONAL INPUT PARAMETERS: None. KEYWORD PARAMETERS: None. OUTPUTS: xmean - weighted mean sigmam - standard deviation of mean sigmad - standard deviation of data COMMON BLOCKS: None. SIDE EFFECTS: None. RESTRICTIONS: None. PROCEDURE: MODIFICATION HISTORY: Written by Marc W. Buie, Lowell Observatory, 1992 Feb 20