NAME: slope PURPOSE: (one line) Compute slope of a line using part of the data. DESCRIPTION: The left and right hand values are computed from the mean of the input data array from -width to +width about the mid-point of the bin. The slope is derived from these means and the uncertainty comes from propagating the uncertainties. CATEGORY: Function fitting CALLING SEQUENCE: coeff=slope(a,b,width,x,y) INPUTS: a - Mid-point of the left hand bin in units of x. b - Mid-point of the right hand bin in units of x. width - Half-width of each bin. x - Independant values of x-y relationship. y - Dependant values to get slope from. OPTIONAL INPUT PARAMETERS: KEYWORD PARAMETERS: OUTPUTS: Return value is a vector, [slope,ds], which is the slope of the line from a to b and ds is the uncertainty on the slope. COMMON BLOCKS: SIDE EFFECTS: Left, right values and slope are printed to the screen. RESTRICTIONS: PROCEDURE: MODIFICATION HISTORY: Written by Marc W. Buie, Lowell Observatory.