From cd85d3696be4a7ee65b0cf6669fc62dc4841aef3 Mon Sep 17 00:00:00 2001 From: Jaron Kent-Dobias Date: Wed, 18 Jul 2018 15:37:27 -0400 Subject: - added support for computing spatial fourier transforms - measurements now are functions passed to wolff in array --- lib/correlation.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 lib/correlation.h (limited to 'lib/correlation.h') diff --git a/lib/correlation.h b/lib/correlation.h new file mode 100644 index 0000000..5722aab --- /dev/null +++ b/lib/correlation.h @@ -0,0 +1,36 @@ + +#pragma once + +#include "types.h" +#include "state.h" + +#include + +template +double correlation_length(const state_t *s) { + double *data = (double *)fftw_malloc(s->nv * sizeof(double)); + int rank = s->D; + int *n = (int *)malloc(rank * sizeof(int)); + fftw_r2r_kind *kind = (fftw_r2r_kind *)malloc(rank * sizeof(fftw_r2r_kind)); + for (D_t i = 0; i < rank; i++) { + n[i] = s->L; + kind[i] = FFTW_R2HC; + } + fftw_plan plan = fftw_plan_r2r(rank, n, data, data, kind, 0); + + for (v_t i = 0; i < s->nv; i++) { + data[i] = correlation_component(s->spins[i]); + } + + fftw_execute(plan); + + double length = pow(data[0], 2); + + fftw_destroy_plan(plan); + fftw_free(data); + free(n); + free(kind); + + return length; +} + -- cgit v1.2.3-70-g09d2