numerical Casimir–Polder integration
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| real(kind=wp), | intent(in) | :: | pol(23) |
pure function trapzd(pol) real(wp), intent(in) :: pol(23) real(wp) :: trapzd real(wp), parameter :: freq(23) = [ & & 0.000001_wp, 0.050000_wp, 0.100000_wp, & & 0.200000_wp, 0.300000_wp, 0.400000_wp, & & 0.500000_wp, 0.600000_wp, 0.700000_wp, & & 0.800000_wp, 0.900000_wp, 1.000000_wp, & & 1.200000_wp, 1.400000_wp, 1.600000_wp, & & 1.800000_wp, 2.000000_wp, 2.500000_wp, & & 3.000000_wp, 4.000000_wp, 5.000000_wp, & & 7.500000_wp, 10.00000_wp] real(wp), parameter :: weights(23) = 0.5_wp * [ & & ( freq (2) - freq (1) ), & & ( freq (2) - freq (1) ) + ( freq (3) - freq (2) ), & & ( freq (3) - freq (2) ) + ( freq (4) - freq (3) ), & & ( freq (4) - freq (3) ) + ( freq (5) - freq (4) ), & & ( freq (5) - freq (4) ) + ( freq (6) - freq (5) ), & & ( freq (6) - freq (5) ) + ( freq (7) - freq (6) ), & & ( freq (7) - freq (6) ) + ( freq (8) - freq (7) ), & & ( freq (8) - freq (7) ) + ( freq (9) - freq (8) ), & & ( freq (9) - freq (8) ) + ( freq(10) - freq (9) ), & & ( freq(10) - freq (9) ) + ( freq(11) - freq(10) ), & & ( freq(11) - freq(10) ) + ( freq(12) - freq(11) ), & & ( freq(12) - freq(11) ) + ( freq(13) - freq(12) ), & & ( freq(13) - freq(12) ) + ( freq(14) - freq(13) ), & & ( freq(14) - freq(13) ) + ( freq(15) - freq(14) ), & & ( freq(15) - freq(14) ) + ( freq(16) - freq(15) ), & & ( freq(16) - freq(15) ) + ( freq(17) - freq(16) ), & & ( freq(17) - freq(16) ) + ( freq(18) - freq(17) ), & & ( freq(18) - freq(17) ) + ( freq(19) - freq(18) ), & & ( freq(19) - freq(18) ) + ( freq(20) - freq(19) ), & & ( freq(20) - freq(19) ) + ( freq(21) - freq(20) ), & & ( freq(21) - freq(20) ) + ( freq(22) - freq(21) ), & & ( freq(22) - freq(21) ) + ( freq(23) - freq(22) ), & & ( freq(23) - freq(22) ) ] trapzd = sum(pol*weights) end function trapzd