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29 lines
801 B
ReStructuredText
29 lines
801 B
ReStructuredText
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==============
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bitmask module
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==============
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The central part of this module is the :file:`bitmasks_module.f90` file. It contains
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the constants that will be used to define on which kind of integer the bitmasks
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will be defined.
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In the program, to represent a determinant as a pair of bitstrings,
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the determinant should be defined as
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.. code-block:: fortran
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use bitmasks
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integer(bit_kind) :: determinant(N_int,2)
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:file:`bitmasks_routines.irp.f` contains helper routines to manipulate bitmask, like
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transforming a bit string to a list of integers for example.
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`bit_kind_shift`, `bit_kind_size` and `bit_kind` are supposed to be consistent::
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2**bit_kind_shift = bit_kind_size
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bit_kind = bit_kind_size / 8
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For an example of how to use the bitmaks, see the file :file:`example.irp.f`.
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