CONTOUR-MAP

Make a plot of any slice of the spectral data cube. Select the plot axes using SET-MAP-SCALES, while various other features can be turned on or off using SET-MAP-PARAMETERS.

The program integrates the intensity over the nominated range of the third ``z-axis'' coordinate (most commonly velocity), and if AVERAGE intensity over the range is selected, then divides by the overall z-axis range to produce an average intensity (otherwise just the integrated total is plotted). If smoothing is selected in SET-MAP-PARAMETERS then the data plane is interpolated onto a finer sampling before plotting, which yields a more aesthetically pleasing image.

If zero sizes are selected in SET-MAP-SIZE then the routine uses the available graphics area to its fullest; if zero limits are selected in SET-MAP-SCALES then the routine plots the entire available data set.

Note that the routine only plots contours in ``cells'' which have real data at all four vertices. Thus if the map has 5-arcsecond cells, but only has measured data at 10-arcsecond sampling, then nothing will appear! Use INTERPOLATE-MAP to generate values for the missing points, and then CONTOUR.

Relevant flags:

AUTO_CONT	L4	Set contour levels automatically based on map max and min.
INTERACTIVE	L4	Enter interactive graphics mode after plotting.
LINTYP_POS	I4	Mongo line type for positive contours [0].
LINTYP_NEG	I4	Mongo line type for negative contours [1].
LINTYP_ZERO	I4	Mongo line type for zero contours [2].
LINE_WEIGHT	I4	Default line weight for plotting axes, labels etc.
NCONT	I4	Number of contours to be plotted.
CONTOUR_0	R4	Bottom contour.
CONTOUR_INT	R4	Contour interval.
NCSET	I4	Number of contours set manually.
CONTOUR_LEVS(16)	R4	Manually set contours.

Examples:

    >> contour-map
    Velo range? (km/s  ) [ -10.0000,  20.0000] <CR>
    Integrated intensity? (rather than average) (Y/N) [N] <CR>
    R.A. offset scaled from   80.000 to  -60.000
    Dec. offset scaled from   30.000 to  -30.000