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                        RELEASE NOTES FOR HEASOFT 6.22.1
                               October 11, 2017
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The HEASoft 6.22.1 release is driven by updates to the NICER data analysis
software and to bug fixes in the FV (FitsViewer) GUI, but also includes
minor updates to some other tasks.

As before, configuration-related changes thoughout the package mean that
users who already have HEASoft v6.x.x installed will need to completely
replace their software installation; there is no clean way to simply
overlay this new release or to update an existing installation.

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                                     NICER
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NICER DAS Version 2.0:

- nicercal, nimaketime, nimpucal, nimpumerge: Minor bug fixes.

- nicerclean (NEW): Produce NICER merged and cleaned event lists.

- nicermergeclean (NEW): Merge NICER MPU data and apply standard screening,
  for convenience of final filtering.

- niextract-events: Add comment metadata for keywords; ensure GTI is upper case.

- nimpumerge: Allow mpulist=7 to merge already-merged ufa files.

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                                      FV
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- Updated ITcl, ITk, and IWidgets packages to v4.1.0.  This fixes a
  problem with expansion of vector table columns and other minor issues.

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                                   HEATOOLS
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- ftmgtime: Allow extensions named with '*GTI*' or '*gti*' (now accepts lower 
  case).

- ftsort: Now handles tables with large numbers of rows or bytes properly;
  internally these were treated inconsistently which led to overflow and
  segmentation faults.

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                                    FUTILS
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- chimgtyp: Do not copy BZERO or BSCALE from a FLOAT/DOUBLE image.  This
  fixes the problem of output integer images with two sets of BZERO/BSCALE
  keywords when input is type float.

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                                    CFITSIO
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Update to version 3.42:

- Fixed memory violation in ffmvec function.

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                                     XSPEC
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HEASoft 6.22.1 includes Xspec v12.9.1p. See the Xspec issues page for
more information:

 https://heasarc.gsfc.nasa.gov/lheasoft/xanadu/xspec/issues/issues.html

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                                      MISC
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- Updated PNG configure option to handle --without-png or --with-png=no,
  thereby allowing users to disable the PNG driver in PGPLOT (enabled by
  default).

- Only use "-ffloat-store" compiler flag for 32-bit builds; its use on
  64-bit processors was reducing optimization and causing some noticeable
  slowness in e.g. Xspec.