Table of Contents

**ccdhist
in=**infile [parameter=value]

The median is also optionally computed, for which an alternate sorting routine can be selected (if available).

Using the **nsigma** keyword, outliers
can be removed and statistics re-computed (a.k.a. sigma-clipping).

This program
was derived from *tabhist(1NEMO)*
, which works on ASCII tables, and derived
much of it’s user interface from that program.

**in=***infile*- input file, in tabular format [no default].
**xmin=***x_min*- Minimum value along X-axis to include [default: autoscaling on minimum of datapoints].
**xmax=***x_max*- Maximum value along X-axis to include [default: autoscaling on maximum of datapoints].
**bins=***n_bins*- If one number is given, it is the number of
(equal size) bins between min and max. If more than one number is given,
they are the bin edges (thus one more than the number of bins need to be
supplied). [default:
**16**]. **maxcount=***count*- Maximum count value per bin plotted along the Y-axis [default: autoscaling].
**ylog=t|f**- Take log of Y-axis? This
option is really redundant, since
*tabmath(1NEMO)*can handle any transformation [default:**f**]. **xlab=***x-label*- Label along the X-axis [default:
**value**]. **ylab=***y-label*- Label along the Y-axis [default:
**N**or**log(N)**]. **headline=***text*- Random verbiage,
will be plotted along right top of plot for identification [default: none].
The left top will contain the filename
*infile*. **tab=t|f**- Table output? If false,
a plot using your current
*yapp(5NEMO)*device will be given. If true, a simple ascii version of a histogram is shown. The default choice of**bins=16**keeps all the information on a simple 80*24 screen. [Default:**f**] **gauss=t|f**- If true,
plot output will contain a gaussian fit. The "best" gaussian fit is the
one that has the same mean, dispersion and integrated area as the data.
[Default:
**t**]. **residual=t|f**- If true, the residual (data - fit) will be plotted
as a dashed line. [Default:
**t**]. **cumul=t|f**- Plot a cumulative histogram instead.
If set, the keywords gauss, residual, and ylog are automatically re-set
to false. [Default:
**f**]. **integrate=t|f**- Integrate the cumulative histogram,
instead of number count. This option makes no sense when cumulative is not
selected. [Default:
**f**]. **median=t|f**- Compute median too? This can be timeconsuming
for large numbers of points. [Default:
**t**]. **nsigma=**- Delete points more than nsigma times the sigma from the mean. Also known as sigma-clipping. After each point sigma and mean are recomputed. [Default: none]
**xcoord=**- Draw additional vertical coordinate lines along these X values. By default, not used.
**sort=***sort_mode*- Sort mode {qsort;...} [qsort]
**dual=t|f**- Dual pass over the data, subtracting the mean. This can be important if the data have a large average value with a small spread around the mean. Notice that in this mode the mean is subtracted but never added to the min/max/mean/median etc. Default: f
**blankval=**- If used, use this as blankval. Default: none.
**scale=**- Scale factor for data [1]

~/src/image/miscsources

8-feb-2011V1.0: cloned off tabhistPJT