From 43f06890e2689af2ef54c4480fe5790692a24f65 Mon Sep 17 00:00:00 2001 From: Elizabeth Hunt Date: Wed, 11 Oct 2023 10:04:04 -0600 Subject: deprecate common lisp solutions and write c; it's too much effort to keep up with the requirements for an archive. --- src/lin.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 src/lin.c (limited to 'src/lin.c') diff --git a/src/lin.c b/src/lin.c new file mode 100644 index 0000000..2df6f28 --- /dev/null +++ b/src/lin.c @@ -0,0 +1,19 @@ +#include "lizfcm.h" +#include + +Line *least_squares_lin_reg(Array_double *x, Array_double *y) { + assert(x->size == y->size); + + uint64_t n = x->size; + double sum_x = sum_v(x); + double sum_y = sum_v(y); + double sum_xy = dot_v(x, y); + double sum_xx = dot_v(x, x); + double denom = ((n * sum_xx) - (sum_x * sum_x)); + + Line *line = malloc(sizeof(Line)); + line->m = ((sum_xy * n) - (sum_x * sum_y)) / denom; + line->a = ((sum_y * sum_xx) - (sum_x * sum_xy)) / denom; + + return line; +} -- cgit v1.3