Merge pull request #127 from argriffing/interval-frobenius-norm

add interval frobenius norm
This commit is contained in:
Fredrik Johansson 2016-04-06 22:34:05 +02:00
commit 508583b0f8
12 changed files with 640 additions and 139 deletions

View file

@ -150,7 +150,9 @@ void acb_mat_transpose(acb_mat_t mat1, const acb_mat_t mat2);
void acb_mat_bound_inf_norm(mag_t b, const acb_mat_t A);
void acb_mat_bound_fro_norm(mag_t b, const acb_mat_t A);
void acb_mat_frobenius_norm(arb_t res, const acb_mat_t A, slong prec);
void acb_mat_bound_frobenius_norm(mag_t b, const acb_mat_t A);
/* Arithmetic */

View file

@ -26,7 +26,7 @@
#include "acb_mat.h"
void
acb_mat_bound_fro_norm(mag_t b, const acb_mat_t A)
acb_mat_bound_frobenius_norm(mag_t b, const acb_mat_t A)
{
slong i, j, r, c;
mag_t t;
@ -45,7 +45,7 @@ acb_mat_bound_fro_norm(mag_t b, const acb_mat_t A)
{
for (j = 0; j < c; j++)
{
acb_ptr z = acb_mat_entry(A, i, j);
acb_srcptr z = acb_mat_entry(A, i, j);
arb_get_mag(t, acb_realref(z));
mag_addmul(b, t, t);
arb_get_mag(t, acb_imagref(z));

52
acb_mat/frobenius_norm.c Normal file
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@ -0,0 +1,52 @@
/*=============================================================================
This file is part of ARB.
ARB is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
ARB is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ARB; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2016 Arb authors
******************************************************************************/
#include "acb_mat.h"
void
acb_mat_frobenius_norm(arb_t res, const acb_mat_t A, slong prec)
{
slong i, j, r, c;
r = acb_mat_nrows(A);
c = acb_mat_ncols(A);
arb_zero(res);
if (r == 0 || c == 0)
return;
for (i = 0; i < r; i++)
{
for (j = 0; j < c; j++)
{
acb_srcptr z = acb_mat_entry(A, i, j);
arb_addmul(res, acb_realref(z), acb_realref(z), prec);
arb_addmul(res, acb_imagref(z), acb_imagref(z), prec);
}
}
arb_sqrtpos(res, res, prec);
}

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@ -0,0 +1,278 @@
/*=============================================================================
This file is part of ARB.
ARB is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
ARB is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ARB; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2016 Arb authors
******************************************************************************/
#include "acb_mat.h"
static void
_acb_mat_set_fmpq_mat_fmpq_mat(acb_mat_t C,
const fmpq_mat_t rsrc, const fmpq_mat_t isrc, slong prec)
{
slong i, j;
for (i = 0; i < acb_mat_nrows(C); i++)
{
for (j = 0; j < acb_mat_ncols(C); j++)
{
arb_set_fmpq(acb_realref(acb_mat_entry(C, i, j)),
fmpq_mat_entry(rsrc, i, j), prec);
arb_set_fmpq(acb_imagref(acb_mat_entry(C, i, j)),
fmpq_mat_entry(isrc, i, j), prec);
}
}
}
static void
_acb_mat_conjugate_transpose(acb_mat_t B, const acb_mat_t A)
{
slong i, j;
acb_mat_transpose(B, A);
for (i = 0; i < acb_mat_nrows(B); i++)
for (j = 0; j < acb_mat_ncols(B); j++)
acb_conj(acb_mat_entry(B, i, j), acb_mat_entry(B, i, j));
}
static void
_fmpq_mat_sum_of_squares(fmpq_t res, const fmpq_mat_t Q)
{
slong i, j;
fmpq_zero(res);
for (i = 0; i < fmpq_mat_nrows(Q); i++)
{
for (j = 0; j < fmpq_mat_ncols(Q); j++)
{
fmpq_addmul(res, fmpq_mat_entry(Q, i, j), fmpq_mat_entry(Q, i, j));
}
}
}
int main()
{
slong iter;
flint_rand_t state;
flint_printf("frobenius_norm....");
fflush(stdout);
flint_randinit(state);
/* compare to the exact rational norm */
for (iter = 0; iter < 10000; iter++)
{
fmpq_mat_t Qr, Qi;
fmpq_t q;
acb_mat_t A;
slong n, qbits, prec;
n = n_randint(state, 8);
qbits = 1 + n_randint(state, 100);
prec = 2 + n_randint(state, 200);
fmpq_mat_init(Qr, n, n);
fmpq_mat_init(Qi, n, n);
fmpq_init(q);
acb_mat_init(A, n, n);
fmpq_mat_randtest(Qr, state, qbits);
fmpq_mat_randtest(Qi, state, qbits);
/* compute the square of the exact rational norm */
{
fmpq_t qr, qi;
fmpq_init(qr);
fmpq_init(qi);
_fmpq_mat_sum_of_squares(qr, Qr);
_fmpq_mat_sum_of_squares(qi, Qi);
fmpq_add(q, qr, qi);
fmpq_clear(qr);
fmpq_clear(qi);
}
_acb_mat_set_fmpq_mat_fmpq_mat(A, Qr, Qi, prec);
/* check that the arb interval contains the exact value */
{
arb_t a;
arb_init(a);
acb_mat_frobenius_norm(a, A, prec);
arb_mul(a, a, a, prec);
if (!arb_contains_fmpq(a, q))
{
flint_printf("FAIL (containment, iter = %wd)\n", iter);
flint_printf("n = %wd, prec = %wd\n", n, prec);
flint_printf("\n");
flint_printf("Qr = \n"); fmpq_mat_print(Qr); flint_printf("\n\n");
flint_printf("Qi = \n"); fmpq_mat_print(Qi); flint_printf("\n\n");
flint_printf("frobenius_norm(Q)^2 = \n");
fmpq_print(q); flint_printf("\n\n");
flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("frobenius_norm(A)^2 = \n");
arb_printd(a, 15); flint_printf("\n\n");
flint_printf("frobenius_norm(A)^2 = \n");
arb_print(a); flint_printf("\n\n");
abort();
}
arb_clear(a);
}
/* check that the upper bound is not less than the exact value */
{
mag_t b;
fmpq_t y;
mag_init(b);
fmpq_init(y);
acb_mat_bound_frobenius_norm(b, A);
mag_mul(b, b, b);
mag_get_fmpq(y, b);
if (fmpq_cmp(q, y) > 0)
{
flint_printf("FAIL (bound, iter = %wd)\n", iter);
flint_printf("n = %wd, prec = %wd\n", n, prec);
flint_printf("\n");
flint_printf("Qr = \n"); fmpq_mat_print(Qr); flint_printf("\n\n");
flint_printf("Qi = \n"); fmpq_mat_print(Qi); flint_printf("\n\n");
flint_printf("frobenius_norm(Q)^2 = \n");
fmpq_print(q); flint_printf("\n\n");
flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("bound_frobenius_norm(A)^2 = \n");
mag_printd(b, 15); flint_printf("\n\n");
flint_printf("bound_frobenius_norm(A)^2 = \n");
mag_print(b); flint_printf("\n\n");
abort();
}
mag_clear(b);
fmpq_clear(y);
}
fmpq_mat_clear(Qr);
fmpq_mat_clear(Qi);
fmpq_clear(q);
acb_mat_clear(A);
}
/* check trace(A^H A) = frobenius_norm(A)^2 */
for (iter = 0; iter < 10000; iter++)
{
slong m, n, prec;
acb_mat_t A, AH, AHA;
acb_t t;
prec = 2 + n_randint(state, 200);
m = n_randint(state, 10);
n = n_randint(state, 10);
acb_mat_init(A, m, n);
acb_mat_init(AH, n, m);
acb_mat_init(AHA, n, n);
acb_init(t);
acb_mat_randtest(A, state, 2 + n_randint(state, 100), 10);
_acb_mat_conjugate_transpose(AH, A);
acb_mat_mul(AHA, AH, A, prec);
acb_mat_trace(t, AHA, prec);
acb_sqrt(t, t, prec);
/* check the norm bound */
{
mag_t low, frobenius;
mag_init(low);
acb_get_mag_lower(low, t);
mag_init(frobenius);
acb_mat_bound_frobenius_norm(frobenius, A);
if (mag_cmp(low, frobenius) > 0)
{
flint_printf("FAIL (frobenius norm bound)\n", iter);
flint_printf("m = %wd, n = %wd, prec = %wd\n", m, n, prec);
flint_printf("\n");
flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("lower(sqrt(trace(A^H A))) = \n");
mag_printd(low, 15); flint_printf("\n\n");
flint_printf("bound_frobenius_norm(A) = \n");
mag_printd(frobenius, 15); flint_printf("\n\n");
abort();
}
mag_clear(low);
mag_clear(frobenius);
}
/* check the norm interval */
{
arb_t frobenius;
arb_init(frobenius);
acb_mat_frobenius_norm(frobenius, A, prec);
if (!arb_overlaps(acb_realref(t), frobenius))
{
flint_printf("FAIL (frobenius norm overlap)\n", iter);
flint_printf("m = %wd, n = %wd, prec = %wd\n", m, n, prec);
flint_printf("\n");
flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("sqrt(trace(A^H A)) = \n");
acb_printd(t, 15); flint_printf("\n\n");
flint_printf("frobenius_norm(A) = \n");
arb_printd(frobenius, 15); flint_printf("\n\n");
abort();
}
arb_clear(frobenius);
}
acb_mat_clear(A);
acb_mat_clear(AH);
acb_mat_clear(AHA);
acb_clear(t);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");
return EXIT_SUCCESS;
}

View file

@ -25,16 +25,6 @@
#include "acb_mat.h"
static void
_acb_mat_conjugate_transpose(acb_mat_t B, const acb_mat_t A)
{
slong i, j;
acb_mat_transpose(B, A);
for (i = 0; i < acb_mat_nrows(B); i++)
for (j = 0; j < acb_mat_ncols(B); j++)
acb_conj(acb_mat_entry(B, i, j), acb_mat_entry(B, i, j));
}
int main()
{
slong iter;
@ -134,6 +124,7 @@ int main()
flint_printf("trace(ab) = \n"); acb_printd(trab, 15); flint_printf("\n\n");
flint_printf("trace(ba) = \n"); acb_printd(trba, 15); flint_printf("\n\n");
abort();
}
acb_clear(trab);
@ -145,65 +136,6 @@ int main()
acb_mat_clear(ba);
}
/* check trace(A^H A) = frobenius_norm(A)^2 */
for (iter = 0; iter < 10000; iter++)
{
slong m, n, prec;
acb_mat_t A, AH, AHA;
acb_t t;
mag_t low, fro;
prec = 2 + n_randint(state, 200);
m = n_randint(state, 10);
n = n_randint(state, 10);
acb_mat_init(A, m, n);
acb_mat_randtest(A, state, 2 + n_randint(state, 100), 10);
acb_mat_init(AH, n, m);
_acb_mat_conjugate_transpose(AH, A);
acb_mat_init(AHA, n, n);
acb_mat_mul(AHA, AH, A, prec);
acb_init(t);
acb_mat_trace(t, AHA, prec);
acb_sqrt(t, t, prec);
mag_init(low);
acb_get_mag_lower(low, t);
mag_init(fro);
acb_mat_bound_fro_norm(fro, A);
if (mag_cmp(low, fro) > 0)
{
flint_printf("FAIL (frobenius norm)\n", iter);
flint_printf("m = %wd, n = %wd, prec = %wd\n", m, n, prec);
flint_printf("\n");
flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("lower(sqrt(trace(A^H A))) = \n");
mag_printd(low, 15); flint_printf("\n\n");
flint_printf("upper(frobenius_norm(A)) = \n");
mag_printd(fro, 15); flint_printf("\n\n");
abort();
}
acb_clear(t);
mag_clear(low);
mag_clear(fro);
acb_mat_clear(A);
acb_mat_clear(AH);
acb_mat_clear(AHA);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");

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@ -142,7 +142,9 @@ void arb_mat_transpose(arb_mat_t mat1, const arb_mat_t mat2);
void arb_mat_bound_inf_norm(mag_t b, const arb_mat_t A);
void arb_mat_bound_fro_norm(mag_t b, const arb_mat_t A);
void arb_mat_frobenius_norm(arb_t res, const arb_mat_t A, slong prec);
void arb_mat_bound_frobenius_norm(mag_t b, const arb_mat_t A);
/* Arithmetic */

View file

@ -26,7 +26,7 @@
#include "arb_mat.h"
void
arb_mat_bound_fro_norm(mag_t b, const arb_mat_t A)
arb_mat_bound_frobenius_norm(mag_t b, const arb_mat_t A)
{
slong i, j, r, c;
mag_t t;

51
arb_mat/frobenius_norm.c Normal file
View file

@ -0,0 +1,51 @@
/*=============================================================================
This file is part of ARB.
ARB is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
ARB is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ARB; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2016 Arb authors
******************************************************************************/
#include "arb_mat.h"
void
arb_mat_frobenius_norm(arb_t res, const arb_mat_t A, slong prec)
{
slong i, j, r, c;
r = arb_mat_nrows(A);
c = arb_mat_ncols(A);
arb_zero(res);
if (r == 0 || c == 0)
return;
for (i = 0; i < r; i++)
{
for (j = 0; j < c; j++)
{
arb_srcptr x = arb_mat_entry(A, i, j);
arb_addmul(res, x, x, prec);
}
}
arb_sqrtpos(res, res, prec);
}

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@ -0,0 +1,235 @@
/*=============================================================================
This file is part of ARB.
ARB is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
ARB is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ARB; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2016 Arb authors
******************************************************************************/
#include "arb_mat.h"
static void
_fmpq_mat_sum_of_squares(fmpq_t res, const fmpq_mat_t Q)
{
slong i, j;
fmpq_zero(res);
for (i = 0; i < fmpq_mat_nrows(Q); i++)
{
for (j = 0; j < fmpq_mat_ncols(Q); j++)
{
fmpq_addmul(res, fmpq_mat_entry(Q, i, j), fmpq_mat_entry(Q, i, j));
}
}
}
int main()
{
slong iter;
flint_rand_t state;
flint_printf("frobenius_norm....");
fflush(stdout);
flint_randinit(state);
/* compare to the exact rational norm */
for (iter = 0; iter < 10000; iter++)
{
fmpq_mat_t Q;
fmpq_t q;
arb_mat_t A;
slong n, qbits, prec;
n = n_randint(state, 8);
qbits = 1 + n_randint(state, 100);
prec = 2 + n_randint(state, 200);
fmpq_mat_init(Q, n, n);
fmpq_init(q);
arb_mat_init(A, n, n);
fmpq_mat_randtest(Q, state, qbits);
_fmpq_mat_sum_of_squares(q, Q);
arb_mat_set_fmpq_mat(A, Q, prec);
/* check that the arb interval contains the exact value */
{
arb_t a;
arb_init(a);
arb_mat_frobenius_norm(a, A, prec);
arb_mul(a, a, a, prec);
if (!arb_contains_fmpq(a, q))
{
flint_printf("FAIL (containment, iter = %wd)\n", iter);
flint_printf("n = %wd, prec = %wd\n", n, prec);
flint_printf("\n");
flint_printf("Q = \n"); fmpq_mat_print(Q); flint_printf("\n\n");
flint_printf("frobenius_norm(Q)^2 = \n");
fmpq_print(q); flint_printf("\n\n");
flint_printf("A = \n"); arb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("frobenius_norm(A)^2 = \n");
arb_printd(a, 15); flint_printf("\n\n");
flint_printf("frobenius_norm(A)^2 = \n");
arb_print(a); flint_printf("\n\n");
abort();
}
arb_clear(a);
}
/* check that the upper bound is not less than the exact value */
{
mag_t b;
fmpq_t y;
mag_init(b);
fmpq_init(y);
arb_mat_bound_frobenius_norm(b, A);
mag_mul(b, b, b);
mag_get_fmpq(y, b);
if (fmpq_cmp(q, y) > 0)
{
flint_printf("FAIL (bound, iter = %wd)\n", iter);
flint_printf("n = %wd, prec = %wd\n", n, prec);
flint_printf("\n");
flint_printf("Q = \n"); fmpq_mat_print(Q); flint_printf("\n\n");
flint_printf("frobenius_norm(Q)^2 = \n");
fmpq_print(q); flint_printf("\n\n");
flint_printf("A = \n"); arb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("bound_frobenius_norm(A)^2 = \n");
mag_printd(b, 15); flint_printf("\n\n");
flint_printf("bound_frobenius_norm(A)^2 = \n");
mag_print(b); flint_printf("\n\n");
abort();
}
mag_clear(b);
fmpq_clear(y);
}
fmpq_mat_clear(Q);
fmpq_clear(q);
arb_mat_clear(A);
}
/* check trace(A^T A) = frobenius_norm(A)^2 */
for (iter = 0; iter < 10000; iter++)
{
slong m, n, prec;
arb_mat_t A, AT, ATA;
arb_t t;
prec = 2 + n_randint(state, 200);
m = n_randint(state, 10);
n = n_randint(state, 10);
arb_mat_init(A, m, n);
arb_mat_init(AT, n, m);
arb_mat_init(ATA, n, n);
arb_init(t);
arb_mat_randtest(A, state, 2 + n_randint(state, 100), 10);
arb_mat_transpose(AT, A);
arb_mat_mul(ATA, AT, A, prec);
arb_mat_trace(t, ATA, prec);
arb_sqrt(t, t, prec);
/* check the norm bound */
{
mag_t low, frobenius;
mag_init(low);
arb_get_mag_lower(low, t);
mag_init(frobenius);
arb_mat_bound_frobenius_norm(frobenius, A);
if (mag_cmp(low, frobenius) > 0)
{
flint_printf("FAIL (bound)\n", iter);
flint_printf("m = %wd, n = %wd, prec = %wd\n", m, n, prec);
flint_printf("\n");
flint_printf("A = \n"); arb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("lower(sqrt(trace(A^T A))) = \n");
mag_printd(low, 15); flint_printf("\n\n");
flint_printf("bound_frobenius_norm(A) = \n");
mag_printd(frobenius, 15); flint_printf("\n\n");
abort();
}
mag_clear(low);
mag_clear(frobenius);
}
/* check the norm interval */
{
arb_t frobenius;
arb_init(frobenius);
arb_mat_frobenius_norm(frobenius, A, prec);
if (!arb_overlaps(t, frobenius))
{
flint_printf("FAIL (overlap)\n", iter);
flint_printf("m = %wd, n = %wd, prec = %wd\n", m, n, prec);
flint_printf("\n");
flint_printf("A = \n"); arb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("sqrt(trace(A^T A)) = \n");
arb_printd(t, 15); flint_printf("\n\n");
flint_printf("frobenius_norm(A) = \n");
arb_printd(frobenius, 15); flint_printf("\n\n");
abort();
}
arb_clear(frobenius);
}
arb_mat_clear(A);
arb_mat_clear(AT);
arb_mat_clear(ATA);
arb_clear(t);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");
return EXIT_SUCCESS;
}

View file

@ -136,65 +136,6 @@ int main()
arb_mat_clear(ba);
}
/* check trace(A^T A) = frobenius_norm(A)^2 */
for (iter = 0; iter < 10000; iter++)
{
slong m, n, prec;
arb_mat_t A, AT, ATA;
arb_t t;
mag_t low, fro;
prec = 2 + n_randint(state, 200);
m = n_randint(state, 10);
n = n_randint(state, 10);
arb_mat_init(A, m, n);
arb_mat_randtest(A, state, 2 + n_randint(state, 100), 10);
arb_mat_init(AT, n, m);
arb_mat_transpose(AT, A);
arb_mat_init(ATA, n, n);
arb_mat_mul(ATA, AT, A, prec);
arb_init(t);
arb_mat_trace(t, ATA, prec);
arb_sqrt(t, t, prec);
mag_init(low);
arb_get_mag_lower(low, t);
mag_init(fro);
arb_mat_bound_fro_norm(fro, A);
if (mag_cmp(low, fro) > 0)
{
flint_printf("FAIL (frobenius norm)\n", iter);
flint_printf("m = %wd, n = %wd, prec = %wd\n", m, n, prec);
flint_printf("\n");
flint_printf("A = \n"); arb_mat_printd(A, 15); flint_printf("\n\n");
flint_printf("lower(sqrt(trace(A^T A))) = \n");
mag_printd(low, 15); flint_printf("\n\n");
flint_printf("upper(frobenius_norm(A)) = \n");
mag_printd(fro, 15); flint_printf("\n\n");
abort();
}
arb_clear(t);
mag_clear(low);
mag_clear(fro);
arb_mat_clear(A);
arb_mat_clear(AT);
arb_mat_clear(ATA);
}
flint_randclear(state);
flint_cleanup();
flint_printf("PASS\n");

View file

@ -161,10 +161,14 @@ Norms
Sets *b* to an upper bound for the infinity norm (i.e. the largest
absolute value row sum) of *A*.
.. function:: void acb_mat_bound_fro_norm(mag_t b, const acb_mat_t A)
.. function:: void acb_mat_frobenius_norm(acb_t res, const acb_mat_t A, slong prec)
Sets *b* to an upper bound for the Frobenius norm (i.e. the square root
of the sum of squares of magnitudes of entries) of *A*.
Sets *res* to the Frobenius norm (i.e. the square root of the sum
of squares of entries) of *A*.
.. function:: void acb_mat_bound_frobenius_norm(mag_t res, const acb_mat_t A)
Sets *res* to an upper bound for the Frobenius norm of *A*.
Arithmetic

View file

@ -152,10 +152,14 @@ Norms
Sets *b* to an upper bound for the infinity norm (i.e. the largest
absolute value row sum) of *A*.
.. function:: void arb_mat_bound_fro_norm(mag_t b, const arb_mat_t A)
.. function:: void arb_mat_frobenius_norm(arb_t res, const arb_mat_t A, slong prec)
Sets *b* to an upper bound for the Frobenius norm (i.e. the square root
of the sum of squares of entries) of *A*.
Sets *res* to the Frobenius norm (i.e. the square root of the sum
of squares of entries) of *A*.
.. function:: void arb_mat_bound_frobenius_norm(mag_t res, const arb_mat_t A)
Sets *res* to an upper bound for the Frobenius norm of *A*.
Arithmetic
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