3.3.11. horton/gbasis/gbw.h – A four-center integral wrapper for the Cholesky code¶
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class
GB4IntegralWrapper¶ - #include <gbw.h>
A wrapper around a four-center integral implementation that is suitable for a Cholesky algorithm.
Public Functions
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GB4IntegralWrapper(GOBasis *gobasis, GB4Integral *gb4int)¶ Construct the wrapper.
- Parameters
gobasis: A Gaussian basis set for which the four-center integrals are to be computed.gb4int: A definition/implementation of a four-center integral.
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~GB4IntegralWrapper()¶
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long
get_nbasis()¶ The number of basis functions.
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void
select_2index(long index0, long index2, long *pbegin0, long *pend0, long *pbegin2, long *pend2)¶ Select a pair of shells to which a pair of basis indexes belong.
The output of this function is also stored internally for the next call to the compute method.
- Parameters
index0: The first basis index.index2: The third basis index. (Physicist notation!)pbegin0: Output argument. The begin of the range for the first shell.pend0: Output argument. The end (non-inclusive) of the range for the first shell.pbegin2: Output argument. The begin of the range for the third shell. (Physicist notation!)pend2: Output argument. The end (non-inclusive) of the range for the third shell. (Physicist notation!)
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void
compute()¶ Compute four-center integrals for the slices selected with the select_2index method.
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void
compute_diagonal(double *diagonal)¶ Compute the (double) diagonal of the four-index object. This is usually needed in the initialization of a Cholesky algorithm.
- Parameters
diagonal: The output array to which the result is written (size=nbasis*basis).
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double *
get_2index_slice(long index0, long index2)¶ Get a slice from the four-center integral computed with the last call to the compute method.
- Parameters
index0: The first index of the slice. (Absolute indexes, not relative within the currently selected shell.)index2: The third index of the slice. (Physicist notation!) (Absolute indexes, not relative within the currently selected shell.)
Private Functions
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void
compute_shell(long ishell1, long ishell3)¶ Compute four-center integrals for a quadruplet of shells (defined by ishell0, ishell1, ishell2 and ishell3).
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