calculator/src/CalcManager/Ratpack/transh.cpp

227 lines
5.3 KiB
C++

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.
//-----------------------------------------------------------------------------
// Package Title ratpak
// File transh.c
// Copyright (C) 1995-96 Microsoft
// Date 01-16-95
//
//
// Description
//
// Contains hyperbolic sin, cos, and tan for rationals.
//
//
//-----------------------------------------------------------------------------
#include "ratpak.h"
bool IsValidForHypFunc(PRAT px, int32_t precision)
{
PRAT ptmp = nullptr;
bool bRet = true;
DUPRAT(ptmp, rat_min_exp);
divrat(&ptmp, rat_ten, precision);
if (rat_lt(px, ptmp, precision))
{
bRet = false;
}
destroyrat(ptmp);
return bRet;
}
//-----------------------------------------------------------------------------
//
// FUNCTION: sinhrat, _sinhrat
//
// ARGUMENTS: x PRAT representation of number to take the sine hyperbolic
// of
// RETURN: sinh of x in PRAT form.
//
// EXPLANATION: This uses Taylor series
//
// n
// ___ 2j+1
// \ ] X
// \ ---------
// / (2j+1)!
// /__]
// j=0
// or,
// n
// ___ 2
// \ ] X
// \ thisterm ; where thisterm = thisterm * ---------
// / j j+1 j (2j)*(2j+1)
// /__]
// j=0
//
// thisterm = X ; and stop when thisterm < precision used.
// 0 n
//
// if x is bigger than 1.0 (e^x-e^-x)/2 is used.
//
//-----------------------------------------------------------------------------
void _sinhrat(PRAT* px, int32_t precision)
{
if (!IsValidForHypFunc(*px, precision))
{
// Don't attempt exp of anything large or small
throw(CALC_E_DOMAIN);
}
CREATETAYLOR();
DUPRAT(pret, *px);
DUPRAT(thisterm, pret);
DUPNUM(n2, num_one);
do
{
NEXTTERM(xx, INC(n2) DIVNUM(n2) INC(n2) DIVNUM(n2), precision);
} while (!SMALL_ENOUGH_RAT(thisterm, precision));
DESTROYTAYLOR();
}
void sinhrat(_Inout_ PRAT* px, uint32_t radix, int32_t precision)
{
PRAT tmpx = nullptr;
if (rat_ge(*px, rat_one, precision))
{
DUPRAT(tmpx, *px);
exprat(px, radix, precision);
tmpx->pp->sign *= -1;
exprat(&tmpx, radix, precision);
subrat(px, tmpx, precision);
divrat(px, rat_two, precision);
destroyrat(tmpx);
}
else
{
_sinhrat(px, precision);
}
}
//-----------------------------------------------------------------------------
//
// FUNCTION: coshrat
//
// ARGUMENTS: x PRAT representation of number to take the cosine
// hyperbolic of
//
// RETURN: cosh of x in PRAT form.
//
// EXPLANATION: This uses Taylor series
//
// n
// ___ 2j
// \ ] X
// \ ---------
// / (2j)!
// /__]
// j=0
// or,
// n
// ___ 2
// \ ] X
// \ thisterm ; where thisterm = thisterm * ---------
// / j j+1 j (2j)*(2j+1)
// /__]
// j=0
//
// thisterm = 1 ; and stop when thisterm < precision used.
// 0 n
//
// if x is bigger than 1.0 (e^x+e^-x)/2 is used.
//
//-----------------------------------------------------------------------------
void _coshrat(PRAT* px, uint32_t radix, int32_t precision)
{
if (!IsValidForHypFunc(*px, precision))
{
// Don't attempt exp of anything large or small
throw(CALC_E_DOMAIN);
}
CREATETAYLOR();
pret->pp = i32tonum(1L, radix);
pret->pq = i32tonum(1L, radix);
DUPRAT(thisterm, pret)
n2 = i32tonum(0L, radix);
do
{
NEXTTERM(xx, INC(n2) DIVNUM(n2) INC(n2) DIVNUM(n2), precision);
} while (!SMALL_ENOUGH_RAT(thisterm, precision));
DESTROYTAYLOR();
}
void coshrat(_Inout_ PRAT* px, uint32_t radix, int32_t precision)
{
PRAT tmpx = nullptr;
(*px)->pp->sign = 1;
(*px)->pq->sign = 1;
if (rat_ge(*px, rat_one, precision))
{
DUPRAT(tmpx, *px);
exprat(px, radix, precision);
tmpx->pp->sign *= -1;
exprat(&tmpx, radix, precision);
addrat(px, tmpx, precision);
divrat(px, rat_two, precision);
destroyrat(tmpx);
}
else
{
_coshrat(px, radix, precision);
}
// Since *px might be epsilon below 1 due to TRIMIT
// we need this trick here.
if (rat_lt(*px, rat_one, precision))
{
DUPRAT(*px, rat_one);
}
}
//-----------------------------------------------------------------------------
//
// FUNCTION: tanhrat
//
// ARGUMENTS: x PRAT representation of number to take the tangent
// hyperbolic of
//
// RETURN: tanh of x in PRAT form.
//
// EXPLANATION: This uses sinhrat and coshrat
//
//-----------------------------------------------------------------------------
void tanhrat(_Inout_ PRAT* px, uint32_t radix, int32_t precision)
{
PRAT ptmp = nullptr;
DUPRAT(ptmp, *px);
sinhrat(px, radix, precision);
coshrat(&ptmp, radix, precision);
mulnumx(&((*px)->pp), ptmp->pq);
mulnumx(&((*px)->pq), ptmp->pp);
destroyrat(ptmp);
}