18.1 STSDAS Software

The new tasks fall into two major categories:

1. General-purpose utilities. These tasks include tools for mathematical and statistical operations on science images and for analysis and display of reduced and raw data. In most cases, the new utilities extend existing routines to include error and data quality propagation. These are the utilities of greatest interest to the user community. Under this category are several tasks described in Chapter 3, msarith, mscombine, msstatistics, msjoin and mssplit, along with a few other tasks we describe below, -ndisplay, markdq, and pstack. The first five are found in the package toolbox.imgtools.mstools, the remaining ones reside in the package hst_calib.nicmos.
2. Calibration-oriented utilities. These tasks generate reference files, such as readnoise arrays, dark files, flatfields, non-linearity correction arrays, and bad pixel arrays, to feed the calibration database and to support the calibration pipelines. The tasks are designed specifically for the calibration of NICMOS and will not be of general utility. The tools are mstreakflat, -msbadpix, ndark, nlincorr, and msreadnoise. All are located in the calibration package hst_calib.nicmos. The tasks in the toolbox.imgtools.mstools package are particularly useful for working with individual STIS and NICMOS imsets. See "Working with STIS and NICMOS Imsets" on page 3-12 if you are not familiar with these tasks. Below we describe a few tasks of specific interest to NICMOS observers. For additional details and examples of these and other tools, please refer to the online help.

pstack