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pstats stsdas.hst_calib.nicmos



pstats -- plot a stack of NICMOS or WFC3/IR MultiAccum image statistics


pstats input


Plot statistics for a specified image section up the stack of a NICMOS or WFC3/IR MultiAccum image. Sections from any of the SCI, ERR, DQ, SAMP, or TIME image extensions can be plotted. A choice of mean, median, mode, standard deviation, minimum and maximum statistics is available. The total number of samples is determined from the primary header keyword NSAMP and all samples (excluding the zeroth-read) are plotted. The SCI, ERR, DQ, or SAMP statistics are plotted as a function of sample time, while TIME statistics are plotted as a function of sample number. The sample times are read from the SAMPTIME keyword in the SCI header for each readout. If any of the ERR, DQ, SAMP, or TIME extensions have null data arrays, the value of the PIXVALUE extension header keyword is substituted for the statistics values. The plotted data can be saved to an output text table or printed to the terminal.


input [file]
Input MultiAccum image name with optional image section specification. If no image section is specified, the entire image is used. This should be either a _raw or _ima file, containing all the data from multiple readouts. You must specify just the file name and image section, with no extname designation.
(extname = "sci") [string, allowed values: sci | err | dq | samp | time]
Extension name (EXTNAME keyword value) of data to plot.
(units = "counts") [string, allowed values: counts | rate]
Plot "sci" or "err" data in units of counts or countrate ("rate"). Input data can be in either unit; conversion will be performed automatically. Ignored when plotting "dq", "samp", or "time" data.
(stat = "midpt") [string, allowed values: mean|midpt|mode|stddev|min|max]
Type of statistic to compute.
(logfile = "") [string]
Name of optional output text table in which data are saved. If blank, no file is produced. If set to "STDOUT", data are printed to the terminal.
(title = "") [string]
Title for the plot. If left blank, the name of the input image, appended with the extname and image section, is used.
(xlabel = "") [string]
Label for the X-axis of the plot. If left blank, a suitable default is generated.
(ylabel = "") [string]
Label for the Y-axis of the plot. If left blank, a suitable default based on the plot units and the extname of the data is generated.
(device="stdgraph") [string]
Output device.


1. Plot the median of the SCI image section [100:120,50:75] of image n3t502cur_ima.fits, in units of counts:

 cl> pstats n3t502cur_ima.fits[100:120,50:75]

2. Plot the mean of the entire ERR images in the same file, in units of countrates:

 cl> pstats n3t502cur_ima.fits ext=err units=rate

3. Plot the median of SCI image quadrant 1 ([1:128,1:128]) in image n3uw01a6r_ima.fits, saving the data in a text file "stats.log", and make a postscript file of the plot:

 cl> pstats n3uw01a6r_ima.fits[1:128,1:128] log=stats.log dev=psi_land



Author: Howard Bushouse, SSB


pstack, prow, pcol

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