PDM2DIS

Name

pdm2dis

Purpose (one Line)

Phase disconnect shift search by phase dispersion minimization ($\theta$ based).

Description

This routine computes the Theta statistic to look for the optimum
zero-point shift between two datasets for a given period.
The theta statistic is the same as used for period searching
in time-series data using the technique described by Stellingwerf,
ApJ, 224, pp. 953-960 (1978). The shift reported is that which
is added to the phase of x2 to register with respect to x1.

Calling Sequence

pdm2dis,t1,x1,sig1,t2,x2,sig2,period,shif1,shif2,dshif,shiftv,chi2

Inputs

t1 - independent variable for first dataset (usually time)
x1 - dependent variable for first dataset
(usually magnitude or intensity)
sig1 - Uncertainty on x for first dataset.
t2 - independent variable for first dataset (usually time)
x2 - dependent variable for first dataset
(usually magnitude or intensity)
sig2 - Uncertainty on x for first dataset.
period - Lightcurve period. (same units as t1 and t2).
shif1 - Lower limit to phase shift in fractional rotations
shif2 - Upper limit to phase shift in fractional rotations
dshif - phase shift interval.

Optional Input Parameters

Keyword Parameters

Outputs

shiftv - Zero-point shift vector.
chi2 - PDM statistic (1 ==> perfect, >>1 is bad).
avgyes - Average number of points contained within non-empty bins.
nempty - Total number of empty bins.

Common Blocks

Side Effects

Restrictions

Procedure

Modification History

Written 1992 Feb 13, by Marc W. Buie, Lowell Observatory
95/02/23 - MWB - added NBINS keyword
95/08/03 - MWB, cloned from pdm2shif