Specifying a unit cell on the command line

Many of the collect programs accept a "unit cell orientation" on the command line in the form of a ".rmat" or ".x" file name. Most programs that accept such arguments also accept a number of options to change the cell reduction/standardization algorithms:

notransformtrigonal: Keep trigonal cells in primitive setting
transformtrigonal: Transform trigonal cells to R-centered hexagonal setting. This is the default.
nostandardize: Keep unit cell unchanged, do not attempt to find lattice symmetry.
standardize: Automatically find lattice symmetry. This is the default.
axcrit=#.##: Use the given axis criterium for the cell standardization. By default it will use the same value as has been used before in any cell reduction, or if none has been specified ever, 0.2 degrees. If this criterium is increased, higher symmetry will be generated more easily.
pointgroup=pg: Specify the point group for the data set. By default, the lowest laue group for the crystal system is assumed. A pointgroup can be explicitly specified if the symmetry is known to be higher, or if Friedel opposites are to be treated separately.

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