Type | Intent | Optional | Attributes | Name | ||
---|---|---|---|---|---|---|
integer, | intent(in) | :: | i | |||
integer, | intent(in) | :: | j | |||
integer, | intent(in) | :: | a | |||
integer, | intent(in) | :: | b |
pure integer function ind2(i, j, a, b)
implicit none
integer, intent(in) :: i, j, a, b
integer :: ij, ab, nvirt, nab
ij = (j - 1) * j / 2 + i
ab = (b - 1) * b / 2 + a
nvirt = nbasis - nel
nab = nvirt * (nvirt + 1) / 2
ind2 = (ij - 1) * nab + ab
return
end function ind2