#include "gr_special.h"
#include "gr_vec.h"
#include "gr_poly.h"
int
_gr_poly_sin_cos_series_basecase(gr_ptr s, gr_ptr c, gr_srcptr h, slong hlen,
slong n, int times_pi, gr_ctx_t ctx)
{
slong sz = ctx->sizeof_elem;
int status = GR_SUCCESS;
slong k, alen = FLINT_MIN(n, hlen);
gr_ptr a, t, u;
hlen = FLINT_MIN(hlen, n);
if (times_pi)
status |= gr_sin_cos_pi(s, c, h, ctx);
else
status |= gr_sin_cos(s, c, h, ctx);
if (hlen == 1)
{
status |= _gr_vec_zero(GR_ENTRY(s, 1, sz), n - 1, ctx);
status |= _gr_vec_zero(GR_ENTRY(c, 1, sz), n - 1, ctx);
return status;
}
GR_TMP_INIT_VEC(a, alen + 2, ctx);
t = GR_ENTRY(a, alen, sz);
u = GR_ENTRY(t, 1, sz);
for (k = 1; k < alen; k++)
status |= gr_mul_ui(GR_ENTRY(a, k, sz), GR_ENTRY(h, k, sz), k, ctx);
if (times_pi)
{
status |= gr_pi(t, ctx);
status |= _gr_vec_mul_scalar(GR_ENTRY(a, 1, sz), GR_ENTRY(a, 1, sz), alen - 1, t, ctx);
}
for (k = 1; k < n; k++)
{
slong l = FLINT_MIN(k, hlen - 1);
status |= _gr_vec_dot_rev(t, NULL, 1, GR_ENTRY(a, 1, sz), GR_ENTRY(s, k - l, sz), l, ctx);
status |= _gr_vec_dot_rev(u, NULL, 0, GR_ENTRY(a, 1, sz), GR_ENTRY(c, k - l, sz), l, ctx);
status |= gr_div_ui(GR_ENTRY(c, k, sz), t, k, ctx);
status |= gr_div_ui(GR_ENTRY(s, k, sz), u, k, ctx);
}
GR_TMP_CLEAR_VEC(a, alen + 2, ctx);
return status;
}
int
gr_poly_sin_cos_series_basecase(gr_poly_t s, gr_poly_t c,
const gr_poly_t h, slong n, int times_pi, gr_ctx_t ctx)
{
slong hlen = h->length;
int status = GR_SUCCESS;
if (n == 0)
{
status |= gr_poly_zero(s, ctx);
status |= gr_poly_zero(c, ctx);
return status;
}
if (hlen == 0)
{
status |= gr_poly_zero(s, ctx);
status |= gr_poly_one(c, ctx);
return status;
}
if (hlen == 1)
n = 1;
gr_poly_fit_length(s, n, ctx);
gr_poly_fit_length(c, n, ctx);
status |= _gr_poly_sin_cos_series_basecase(s->coeffs, c->coeffs, h->coeffs, hlen, n, times_pi, ctx);
_gr_poly_set_length(s, n, ctx);
_gr_poly_normalise(s, ctx);
_gr_poly_set_length(c, n, ctx);
_gr_poly_normalise(c, ctx);
return status;
}