Developer information

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Information for developers.

SQW Version of Horace

A new version of Horace has been released, with some major changes compared to the previous version. The main changes are as follows.

  • The addition of a new sqw object, in addition to the dnd objects which existed previously.
  • Changes to the graphics and underlying mathematics. These will now be handled by the Libisis software, replacing MGenie.
  • Changes to the syntax of some commands. Most commands have remained the same, and the information on this website corresponds to the latest release. If you are using an old version of Horace we encourage you to update, since we will not be providing user support for old versions. SQW data files generated by the old versions can still be read by the new version, however there have been a few changes to the cut_sqw command pertaining to the new sqw objects.

The reason for adding the new sqw object type is to allow the detector pixel information contributing to the intensity at any given (Q,E) to be retained. This means that, for example, simulations or fits which require instrumental resolution corrections can now be done properly. An sqw object can have any dimensionality, from 0 to 4, so can be considered to a first approximation as a dnd object with a few extra pieces of information.

The reason for changing the underlying graphics and mathematics to Libisis from MGenie is that MGenie is no longer being updated, corrected, or supported. Hence any low level code errors were unlikely to be found or fixed, which is clearly undesirable. Furthermore Libisis has been worked on more extensively and the speed of the code execution is faster due to improved Fortran routines.

Almost all of the syntax changes in previously extant commands are due to the need to accommodate the sqw object as well as dnd objects.