## Name

occplot

## Purpose (one Line)

Plot small pieces of stellar occultation data.

## Description

This procedure is intended to be used in plotting a very large 1-d

vector as a function of time in which you are only interested in

plotting a small subset of the data. The time calibration is specified

through the tstart and dt input parameters and the time axis is

assumed to be strictly linear. All time calculations are done in

double precision to ensure the full precision of the time axis is

saved. Single precision gives out at the few millisecond level.

The current plotting device is used for output. Some attempt has

been made to see that sensible plots come out even when using the

!p.multi system variable to make multiple plots on a page.

## Category

2-D plotting

## Calling Sequence

occplot,data,tstart,dt,tmid,width[,yspan]

## Inputs

data - Vector containing the time-series occultation data.

tstart - Time, in double precision hours, of the first data point

or a three element vector [h,m,s]

dt - Time increment between points in milliseconds.

tmid - Mid-point of the plot in days or as a three element

vector [h,m,s]

width - Full width of the plot in seconds.

## Optional Input Parameters

yspan - yrange of the plot (centered on the mean). If not supplied

the plot runs from the max to the min of the portion plotted.

If yspan is two-element vector, the two values are used

as the actual yrange on the plot.

## Keyword Parameters

connect - When set, the points are connected by a line.

over - When set, the plot is done as an overlay on the current plot.

psym - Symbol to use for plot.

title - Title for plot

## Outputs

Plot goes to the current graphics device.

## Common Blocks

None.

## Side Effects

None.

## Restrictions

None.

## Modification History

12/29/92 - Written by Marc W. Buie, Lowell Observatory. Patterned

after the zodiac function, 'occgraf'

2/9/93 - Added option for yspan to allow direct specification of

y plotting range. MWB

2/10/93 - Fixed bug with top axis, axis cannot handle long or double

precision numbers.