fix dv in dft_crt

acb_dirichlet.h

@@ -316,7 +316,7 @@ typedef crt_struct crt_t[1];
 
 void crt_init(crt_t c, ulong n);
 
-void crt_decomp(acb_ptr y, acb_srcptr x, const crt_t c, ulong len);
+void crt_decomp(acb_ptr y, acb_srcptr x, slong dx, const crt_t c, ulong len);
 void crt_recomp(acb_ptr y, acb_srcptr x, const crt_t c, ulong len);
 
 typedef struct acb_dirichlet_dft_step_struct acb_dirichlet_dft_step_struct;
@@ -348,6 +348,7 @@ typedef struct
 {
     slong n;
     crt_t c;
+    slong dv;
     /* then a product */
     acb_dirichlet_dft_step_ptr cyc;
 }
@@ -402,6 +403,8 @@ acb_dirichlet_dft_step_struct
 
 /*typedef acb_dirichlet_dft_pre_struct acb_dirichlet_dft_pre_t[1];*/
 
+#define DFT_VERB 0
+
 enum
 {
     DFT_POL, DFT_CYC, DFT_PROD, DFT_CRT /*, DFT_2E, DFT_CONV */
@@ -462,18 +465,17 @@ ACB_DIRICHLET_INLINE void
 acb_dirichlet_dft_pol_clear(acb_dirichlet_dft_pol_t pol)
 {
     if (pol->zclear)
-    {
-        flint_printf("  ## clearing pol [len=%ld]....", pol->n);
         _acb_vec_clear(pol->z, pol->n);
-        flint_printf("done\n");
-    }
 }
 
+void _acb_dirichlet_dft_crt_init(acb_dirichlet_dft_crt_t crt, slong dv, slong len, slong prec);
+
 ACB_DIRICHLET_INLINE void
 acb_dirichlet_dft_crt_init(acb_dirichlet_dft_crt_t crt, slong len, slong prec)
 {
     crt->n = len;
     crt_init(crt->c, len);
+    crt->dv = 1;
     crt->cyc = _acb_dirichlet_dft_steps_prod(crt->c->m, crt->c->num, prec);
 }
 

acb_dirichlet/dft_crt.c

@@ -41,10 +41,9 @@ crt_print(const crt_t c)
     slong k;
     if (c->num == 0)
     {
-        flint_printf("trivial group, absurd\n");
+        flint_printf("trivial group\n");
         abort();
     }
-    flint_printf("crt decomp ");
     for (k = 0; k < c->num; k++)
         flint_printf("Z/%wuZ ", c->m[k]);
     flint_printf("\n");
@@ -100,7 +99,7 @@ reorder_from_crt(acb_srcptr v, crt_t c, ulong len)
 #endif
 
 void
-crt_decomp(acb_ptr y, acb_srcptr x, const crt_t c, ulong len)
+crt_decomp(acb_ptr y, acb_srcptr x, slong dv, const crt_t c, ulong len)
 {
     int j, e[CRT_MAX];
     ulong k, l;
@@ -111,8 +110,7 @@ crt_decomp(acb_ptr y, acb_srcptr x, const crt_t c, ulong len)
     l = 0;
     for(k = 0; k < len; k++)
     {
-        /*flint_printf("set y[%wu] = x[%wu]\n", k, l);*/
+        acb_set(y + k, x + l * dv);
-        acb_set(y + k, x + l);
         for (j = c->num - 1; j >= 0; e[j] = 0, j--)
         {
             e[j]++; l = nmod_add(l, c->vM[j], c->n);
@@ -145,17 +143,12 @@ crt_recomp(acb_ptr y, acb_srcptr x, const crt_t c, ulong len)
 }
 
 void
-acb_dirichlet_dft_crt(acb_ptr w, acb_srcptr v, slong len, slong prec)
+_acb_dirichlet_dft_crt_init(acb_dirichlet_dft_crt_t crt, slong dv, slong len, slong prec)
 {
-    crt_t c;
+    crt->n = len;
-    acb_ptr t;
+    crt_init(crt->c, len);
-    t = _acb_vec_init(len);
+    crt->dv = dv;
-    crt_init(c, len);
+    crt->cyc = _acb_dirichlet_dft_steps_prod(crt->c->m, crt->c->num, prec);
-    crt_print(c);
-    crt_decomp(w, v, c, len);
-    acb_dirichlet_dft_prod(t, w, c->m, c->num, prec);
-    crt_recomp(w, t, c, len);
-    _acb_vec_clear(t, len);
 }
 
 void
@@ -163,9 +156,21 @@ acb_dirichlet_dft_crt_precomp(acb_ptr w, acb_srcptr v, const acb_dirichlet_dft_c
 {
     acb_ptr t;
     t = _acb_vec_init(crt->n);
-    crt_print(crt->c);
+    crt_decomp(w, v, crt->dv, crt->c, crt->n);
-    crt_decomp(w, v, crt->c, crt->n);
     acb_dirichlet_dft_step(t, w, crt->cyc, crt->c->num, prec);
     crt_recomp(w, t, crt->c, crt->n);
     _acb_vec_clear(t, crt->n);
 }
+
+void
+acb_dirichlet_dft_crt(acb_ptr w, acb_srcptr v, slong len, slong prec)
+{
+    crt_t c;
+    acb_ptr t;
+    t = _acb_vec_init(len);
+    crt_init(c, len);
+    crt_decomp(w, v, 1, c, len);
+    acb_dirichlet_dft_prod(t, w, c->m, c->num, prec);
+    crt_recomp(w, t, c, len);
+    _acb_vec_clear(t, len);
+}

acb_dirichlet/dft_cyc.c

@@ -24,14 +24,17 @@ _acb_dirichlet_dft_cyc_init_z_fac(acb_dirichlet_dft_cyc_t t, n_factor_t fac, slo
 
     if (z == NULL)
     {
-        flint_printf("dft_cyc: compute roots of order %wu\n", t->n);
         z = _acb_vec_init(t->n);
         acb_dirichlet_vec_nth_roots(z, t->n, prec);
         dz = 1;
         t->zclear = 1;
     }
     else
+    {
+        if (DFT_VERB)
+            flint_printf("dft_cyc: roots of order %wu already computed\n", t->n);
         t->zclear = 0;
+    }
 
     t->z = z;
 

acb_dirichlet/dft_pol.c

@@ -44,10 +44,10 @@ _acb_dirichlet_dft_pol_init(acb_dirichlet_dft_pol_t pol, slong dv, acb_ptr z, sl
     pol->n = len;
     pol->dv = dv;
 
-    /* warning: if set here, must be cleared somewhere */
     if (z == NULL)
     {
-        flint_printf("warning: init z in dft_pol, should be avoided\n");
+        if (DFT_VERB)
+            flint_printf("warning: init z[%ld] in dft_pol, should be avoided\n",len);
         pol->z = _acb_vec_init(len);
         acb_dirichlet_vec_nth_roots(pol->z, len, prec);
         pol->dz = 1;
@@ -59,5 +59,4 @@ _acb_dirichlet_dft_pol_init(acb_dirichlet_dft_pol_t pol, slong dv, acb_ptr z, sl
         pol->dz = dz;
         pol->zclear = 0;
     }
-    flint_printf("init dft_pol len = %ld, dz = %ld, dv = %ld\n", pol->n, pol->dz, pol->dv);
 }

acb_dirichlet/dft_precomp.c

@@ -41,7 +41,7 @@ _acb_dirichlet_dft_precomp_init(acb_dirichlet_dft_pre_t pre, slong dv, acb_ptr z
         else
         {
             pre->type = DFT_CRT;
-            acb_dirichlet_dft_crt_init(pre->t.crt, len, prec);
+            _acb_dirichlet_dft_crt_init(pre->t.crt, dv, len, prec);
         }
     }
 }

acb_dirichlet/dft_step.c

@@ -54,13 +54,12 @@ acb_dirichlet_dft_step(acb_ptr w, acb_srcptr v, acb_dirichlet_dft_step_ptr cyc,
         }
 
 #if REORDER
-        /* reorder w to avoid shifting in next DFT */
+        /* reorder w to avoid dv shifts in next DFT */
         w2 = flint_malloc(m * M * sizeof(acb_struct)); 
         for (j = 0; j < M; j++)
             for (i = 0; i < m; i++)
                 w2[j + M * i] = w[i + m * j];
 #endif
-        
 
         /* M DFT of size m */
         for (j = 0; j < M; j++)

acb_dirichlet/test/t-dft.c

@@ -19,8 +19,7 @@ int main()
     slong k;
     slong prec = 100, digits = 30;
     slong nq = 13;
-    /*ulong q[13] = { 2, 3, 4, 5, 6, 23, 10, 15, 30, 59, 308, 335, 961};*/
+    ulong q[13] = { 2, 3, 4, 5, 6, 23, 10, 15, 30, 59, 308, 335, 961};
-    ulong q[13] = { 20, 3, 4, 5, 6, 23, 10, 15, 30, 59, 308, 335, 961};
     flint_rand_t state;
 
     slong f, nf = 3;
@@ -50,7 +49,6 @@ int main()
 
             acb_ptr w = (f == 0) ? w1 : w2;
 
-            flint_printf("\ndo dft %s on Z/%wuZ\n", name[f], q[k]);
             func[f](w, v, q[k], prec);
 
             if (f == 0)