* M_APM - mapmhasn.c
*
* Copyright (C) 2000 - 2007 Michael C. Ring
*
* Permission to use, copy, and distribute this software and its
* documentation for any purpose with or without fee is hereby granted,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation.
*
* Permission to modify the software is granted. Permission to distribute
* the modified code is granted. Modifications are to be distributed by
* using the file 'license.txt' as a template to modify the file header.
* 'license.txt' is available in the official MAPM distribution.
*
* This software is provided "as is" without express or implied warranty.
*/
* $Id: mapmhasn.c,v 1.7 2007/12/03 01:53:33 mike Exp $
*
* This file contains the Inverse Hyperbolic SIN, COS, & TAN functions.
*
* $Log: mapmhasn.c,v $
* Revision 1.7 2007/12/03 01:53:33 mike
* Update license
*
* Revision 1.6 2003/07/24 16:28:50 mike
* update arcsinh
*
* Revision 1.5 2003/07/23 23:08:27 mike
* fix problem with arcsinh when input is a very large
* negative number.
*
* Revision 1.4 2003/07/21 20:36:33 mike
* Modify error messages to be in a consistent format.
*
* Revision 1.3 2003/03/31 21:53:21 mike
* call generic error handling function
*
* Revision 1.2 2002/11/03 21:25:03 mike
* Updated function parameters to use the modern style
*
* Revision 1.1 2000/04/03 18:16:29 mike
* Initial revision
*/
#include "m_apm_lc.h"
* arcsinh(x) == log [ x + sqrt(x^2 + 1) ]
*
* also, use arcsinh(-x) == -arcsinh(x)
*/
void m_apm_arcsinh(M_APM rr, int places, M_APM aa)
{
M_APM tmp0, tmp1, tmp2;
if (aa->m_apm_sign == 0)
{
M_set_to_zero(rr);
return;
}
tmp0 = M_get_stack_var();
tmp1 = M_get_stack_var();
tmp2 = M_get_stack_var();
m_apm_absolute_value(tmp0, aa);
m_apm_multiply(tmp1, tmp0, tmp0);
m_apm_add(tmp2, tmp1, MM_One);
m_apm_sqrt(tmp1, (places + 6), tmp2);
m_apm_add(tmp2, tmp0, tmp1);
m_apm_log(rr, places, tmp2);
rr->m_apm_sign = aa->m_apm_sign;
M_restore_stack(3);
}
* arccosh(x) == log [ x + sqrt(x^2 - 1) ]
*
* x >= 1.0
*/
void m_apm_arccosh(M_APM rr, int places, M_APM aa)
{
M_APM tmp1, tmp2;
int ii;
ii = m_apm_compare(aa, MM_One);
if (ii == -1)
{
M_apm_log_error_msg(M_APM_RETURN, "\'m_apm_arccosh\', Argument < 1");
M_set_to_zero(rr);
return;
}
tmp1 = M_get_stack_var();
tmp2 = M_get_stack_var();
m_apm_multiply(tmp1, aa, aa);
m_apm_subtract(tmp2, tmp1, MM_One);
m_apm_sqrt(tmp1, (places + 6), tmp2);
m_apm_add(tmp2, aa, tmp1);
m_apm_log(rr, places, tmp2);
M_restore_stack(2);
}
* arctanh(x) == 0.5 * log [ (1 + x) / (1 - x) ]
*
* |x| < 1.0
*/
void m_apm_arctanh(M_APM rr, int places, M_APM aa)
{
M_APM tmp1, tmp2, tmp3;
int ii, local_precision;
tmp1 = M_get_stack_var();
m_apm_absolute_value(tmp1, aa);
ii = m_apm_compare(tmp1, MM_One);
if (ii >= 0)
{
M_apm_log_error_msg(M_APM_RETURN, "\'m_apm_arctanh\', |Argument| >= 1");
M_set_to_zero(rr);
M_restore_stack(1);
return;
}
tmp2 = M_get_stack_var();
tmp3 = M_get_stack_var();
local_precision = places + 8;
m_apm_add(tmp1, MM_One, aa);
m_apm_subtract(tmp2, MM_One, aa);
m_apm_divide(tmp3, local_precision, tmp1, tmp2);
m_apm_log(tmp2, local_precision, tmp3);
m_apm_multiply(tmp1, tmp2, MM_0_5);
m_apm_round(rr, places, tmp1);
M_restore_stack(3);
}
