/*
calculate arctan (x) with the following series:
x^3 x^5 x^7 x^9
arctan (x) == x - --- + --- - --- + --- ...
3 5 7 9
*/
void M_arctan_near_0(M_APM rr, int places, M_APM aa)
{
M_APM tmp0, tmpR, tmp2, tmpS, digit, term;
int tolerance, local_precision;
long m1;
tmp0 = M_get_stack_var();
tmp2 = M_get_stack_var();
tmpR = M_get_stack_var();
tmpS = M_get_stack_var();
term = M_get_stack_var();
digit = M_get_stack_var();
tolerance = aa->m_apm_exponent - places - 4;
local_precision = places + 8 - aa->m_apm_exponent;
m_apm_copy(term, aa);
m_apm_copy(tmpS, aa);
m_apm_multiply(tmp0, aa, aa);
m_apm_round(tmp2, (local_precision + 8), tmp0);
m1 = 1;
while (TRUE)
{
m1 += 2;
m_apm_set_long(digit, m1);
m_apm_multiply(tmp0, term, tmp2);
m_apm_round(term, local_precision, tmp0);
m_apm_divide(tmp0, local_precision, term, digit);
m_apm_subtract(tmpR, tmpS, tmp0);
if ((tmp0->m_apm_exponent < tolerance) || (tmp0->m_apm_sign == 0))
{
m_apm_round(rr, places, tmpR);
break;
}
m1 += 2;
m_apm_set_long(digit, m1);
m_apm_multiply(tmp0, term, tmp2);
m_apm_round(term, local_precision, tmp0);
m_apm_divide(tmp0, local_precision, term, digit);
m_apm_add(tmpS, tmpR, tmp0);
if ((tmp0->m_apm_exponent < tolerance) || (tmp0->m_apm_sign == 0))
{
m_apm_round(rr, places, tmpS);
break;
}
}
M_restore_stack(6); /* restore the 6 locals we used here */
}
/*
compute int *n = round_to_nearest_int(a / log(2))
M_APM b = MAPM version of *n
returns 0: OK
-1, 1: failure
*/
int M_exp_compute_nn(int *n, M_APM b, M_APM a)
{
M_APM tmp0, tmp1;
void *vp;
char *cp, sbuf[48];
int kk;
*n = 0;
vp = NULL;
cp = sbuf;
tmp0 = M_get_stack_var();
tmp1 = M_get_stack_var();
/* find 'n' and convert it to a normal C int */
/* we just need an approx 1/log(2) for this calculation */
m_apm_multiply(tmp1, a, MM_exp_log2R);
/* round to the nearest int */
if (tmp1->m_apm_sign >= 0)
{
m_apm_add(tmp0, tmp1, MM_0_5);
m_apm_floor(tmp1, tmp0);
}
else
{
m_apm_subtract(tmp0, tmp1, MM_0_5);
m_apm_ceil(tmp1, tmp0);
}
kk = tmp1->m_apm_exponent;
if (kk >= 42)
{
if ((vp = (void *)MAPM_MALLOC((kk + 16) * sizeof(char))) == NULL)
{
/* fatal, this does not return */
M_apm_log_error_msg(M_APM_FATAL, "\'M_exp_compute_nn\', Out of memory");
}
cp = (char *)vp;
}
m_apm_to_integer_string(cp, tmp1);
*n = atoi(cp);
m_apm_set_long(b, (long)(*n));
kk = m_apm_compare(b, tmp1);
if (vp != NULL)
MAPM_FREE(vp);
M_restore_stack(2);
return(kk);
}
/*
calculate log (1 + x) with the following series:
x
y = ----- ( |y| < 1 )
x + 2
[ 1 + y ] y^3 y^5 y^7
log [-------] = 2 * [ y + --- + --- + --- ... ]
[ 1 - y ] 3 5 7
*/
void M_log_near_1(M_APM rr, int places, M_APM xx)
{
M_APM tmp0, tmp1, tmp2, tmpS, term;
int tolerance, dplaces, local_precision;
long m1;
tmp0 = M_get_stack_var();
tmp1 = M_get_stack_var();
tmp2 = M_get_stack_var();
tmpS = M_get_stack_var();
term = M_get_stack_var();
tolerance = xx->m_apm_exponent - (places + 6);
dplaces = (places + 12) - xx->m_apm_exponent;
m_apm_add(tmp0, xx, MM_Two);
m_apm_divide(tmpS, (dplaces + 6), xx, tmp0);
m_apm_copy(term, tmpS);
m_apm_multiply(tmp0, tmpS, tmpS);
m_apm_round(tmp2, (dplaces + 6), tmp0);
m1 = 3L;
while (TRUE)
{
m_apm_multiply(tmp0, term, tmp2);
if ((tmp0->m_apm_exponent < tolerance) || (tmp0->m_apm_sign == 0))
break;
local_precision = dplaces + tmp0->m_apm_exponent;
if (local_precision < 20)
local_precision = 20;
m_apm_set_long(tmp1, m1);
m_apm_round(term, local_precision, tmp0);
m_apm_divide(tmp0, local_precision, term, tmp1);
m_apm_add(tmp1, tmpS, tmp0);
m_apm_copy(tmpS, tmp1);
m1 += 2;
}
m_apm_multiply(tmp0, MM_Two, tmpS);
m_apm_round(rr, places, tmp0);
M_restore_stack(5); /* restore the 5 locals we used here */
}
/*
calculate the exponential function using the following series :
x^2 x^3 x^4 x^5
exp(x) == 1 + x + --- + --- + --- + --- ...
2! 3! 4! 5!
*/
void M_raw_exp(M_APM rr, int places, M_APM xx)
{
M_APM tmp0, digit, term;
int tolerance, local_precision, prev_exp;
long m1;
tmp0 = M_get_stack_var();
term = M_get_stack_var();
digit = M_get_stack_var();
local_precision = places + 8;
tolerance = -(places + 4);
prev_exp = 0;
m_apm_add(rr, MM_One, xx);
m_apm_copy(term, xx);
m1 = 2L;
while (TRUE)
{
m_apm_set_long(digit, m1);
m_apm_multiply(tmp0, term, xx);
m_apm_divide(term, local_precision, tmp0, digit);
m_apm_add(tmp0, rr, term);
m_apm_copy(rr, tmp0);
if ((term->m_apm_exponent < tolerance) || (term->m_apm_sign == 0))
break;
if (m1 != 2L)
{
local_precision = local_precision + term->m_apm_exponent - prev_exp;
if (local_precision < 20)
local_precision = 20;
}
prev_exp = term->m_apm_exponent;
m1++;
}
M_restore_stack(3); /* restore the 3 locals we used here */
}
/*
* functions returns TRUE if the M_APM input number is prime
* FALSE if it is not
*/
int is_number_prime(M_APM input)
{
int ii, ret, index;
char sbuf[32];
/*
* for reference:
*
* table size of 2 to filter multiples of 2 and 3
* table size of 8 to filter multiples of 2, 3 and 5
* table size of 480 to filter multiples of 2,3,5,7, and 11
*
* this increment table will filter out all numbers
* that are multiples of 2,3,5 and 7.
*/
static char incr_table[48] = {
2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 6, 6, 2, 6, 4, 2,
6, 4, 6, 8, 4, 2, 4, 2, 4, 8, 6, 4, 6, 2, 4, 6,
2, 6, 6, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 10, 2, 10 };
/*
* since the real algorithm starts at 11 (to syncronize
* with the increment table), we will cheat for numbers < 10.
*/
if (m_apm_compare(input, MM_Ten) <= 0)
{
m_apm_to_integer_string(sbuf, input);
ii = atoi(sbuf);
if (ii == 2 || ii == 3 || ii == 5 || ii == 7)
return(TRUE);
else
return(FALSE);
}
ret = FALSE;
index = 0;
/*
* see if the input number is a
* multiple of 3, 5, or 7.
*/
m_apm_integer_div_rem(M_quot, M_rem, input, MM_Three);
if (m_apm_sign(M_rem) == 0) /* remainder == 0 */
return(ret);
m_apm_integer_div_rem(M_quot, M_rem, input, MM_Five);
if (m_apm_sign(M_rem) == 0)
return(ret);
m_apm_set_long(M_digit, 7L);
m_apm_integer_div_rem(M_quot, M_rem, input, M_digit);
if (m_apm_sign(M_rem) == 0)
return(ret);
ii = m_apm_exponent(input) + 16;
m_apm_sqrt(M_tmp1, ii, input);
m_apm_add(M_limit, MM_Two, M_tmp1);
m_apm_set_long(M_digit, 11L); /* now start at '11' to check */
while (TRUE)
{
if (m_apm_compare(M_digit, M_limit) >= 0)
{
ret = TRUE;
break;
}
m_apm_integer_div_rem(M_quot, M_rem, input, M_digit);
if (m_apm_sign(M_rem) == 0) /* remainder == 0 */
break;
m_apm_set_long(M_tmp1, (long)incr_table[index]);
m_apm_add(M_tmp0, M_digit, M_tmp1);
m_apm_copy(M_digit, M_tmp0);
if (++index == 48)
index = 0;
}
return(ret);
}
void m_apm_set_long_mt(M_APM atmp, long mm)
{
m_apm_enter();
m_apm_set_long(atmp,mm);
m_apm_leave();
}
MAPM & MAPM::operator=(long l)
{
m_apm_set_long(val(),l);
return *this;
}
MAPM::MAPM(long l)
{
create();
m_apm_set_long(val(),l);
}
void m_apm_log(M_APM r, int places, M_APM a)
{
M_APM tmp0, tmp1, tmp2;
int mexp, dplaces;
if (a->m_apm_sign <= 0)
{
M_apm_log_error_msg(M_APM_RETURN,
"Warning! ... \'m_apm_log\', Negative argument");
M_set_to_zero(r);
return;
}
tmp0 = M_get_stack_var();
tmp1 = M_get_stack_var();
tmp2 = M_get_stack_var();
dplaces = places + 8;
/*
* if the input is real close to 1, use the series expansion
* to compute the log.
*
* 0.9999 < a < 1.0001
*/
m_apm_subtract(tmp0, a, MM_One);
if (tmp0->m_apm_sign == 0) /* is input exactly 1 ?? */
{ /* if so, result is 0 */
M_set_to_zero(r);
M_restore_stack(3);
return;
}
if (tmp0->m_apm_exponent <= -4)
{
M_log_near_1(r, places, tmp0);
M_restore_stack(3);
return;
}
/* make sure our log(10) is accurate enough for this calculation */
/* (and log(2) which is called from M_log_basic_iteration) */
M_check_log_places(dplaces + 25);
mexp = a->m_apm_exponent;
if (mexp >= -4 && mexp <= 4)
{
M_log_basic_iteration(r, places, a);
}
else
{
/*
* use log (x * y) = log(x) + log(y)
*
* here we use y = exponent of our base 10 number.
*
* let 'C' = log(10) = 2.3025850929940....
*
* then log(x * y) = log(x) + ( C * base_10_exponent )
*/
m_apm_copy(tmp2, a);
mexp = tmp2->m_apm_exponent - 2;
tmp2->m_apm_exponent = 2; /* force number between 10 & 100 */
M_log_basic_iteration(tmp0, dplaces, tmp2);
m_apm_set_long(tmp1, (long)mexp);
m_apm_multiply(tmp2, tmp1, MM_lc_log10);
m_apm_add(tmp1, tmp2, tmp0);
m_apm_round(r, places, tmp1);
}
M_restore_stack(3); /* restore the 3 locals we used here */
}
/*
* From Knuth, The Art of Computer Programming:
*
* This is the binary GCD algorithm as described
* in the book (Algorithm B)
*/
void m_apm_gcd(M_APM r, M_APM u, M_APM v)
{
M_APM tmpM, tmpN, tmpT, tmpU, tmpV;
int kk, kr, mm;
long pow_2;
/* 'is_integer' will return 0 || 1 */
if ((m_apm_is_integer(u) + m_apm_is_integer(v)) != 2)
{
M_apm_log_error_msg(M_APM_RETURN,
"Warning! \'m_apm_gcd\', Non-integer input");
M_set_to_zero(r);
return;
}
if (u->m_apm_sign == 0)
{
m_apm_absolute_value(r, v);
return;
}
if (v->m_apm_sign == 0)
{
m_apm_absolute_value(r, u);
return;
}
tmpM = M_get_stack_var();
tmpN = M_get_stack_var();
tmpT = M_get_stack_var();
tmpU = M_get_stack_var();
tmpV = M_get_stack_var();
m_apm_absolute_value(tmpU, u);
m_apm_absolute_value(tmpV, v);
/* Step B1 */
kk = 0;
while (TRUE)
{
mm = 1;
if (m_apm_is_odd(tmpU))
break;
mm = 0;
if (m_apm_is_odd(tmpV))
break;
m_apm_multiply(tmpN, MM_0_5, tmpU);
m_apm_copy(tmpU, tmpN);
m_apm_multiply(tmpN, MM_0_5, tmpV);
m_apm_copy(tmpV, tmpN);
kk++;
}
/* Step B2 */
if (mm)
{
m_apm_negate(tmpT, tmpV);
goto B4;
}
m_apm_copy(tmpT, tmpU);
/* Step: */
B3:
m_apm_multiply(tmpN, MM_0_5, tmpT);
m_apm_copy(tmpT, tmpN);
/* Step: */
B4:
if (m_apm_is_even(tmpT))
goto B3;
/* Step B5 */
if (tmpT->m_apm_sign == 1)
m_apm_copy(tmpU, tmpT);
else
m_apm_negate(tmpV, tmpT);
/* Step B6 */
m_apm_subtract(tmpT, tmpU, tmpV);
if (tmpT->m_apm_sign != 0)
goto B3;
/*
* result = U * 2 ^ kk
*/
if (kk == 0)
m_apm_copy(r, tmpU);
else
{
if (kk == 1)
m_apm_multiply(r, tmpU, MM_Two);
if (kk == 2)
m_apm_multiply(r, tmpU, MM_Four);
if (kk >= 3)
{
mm = kk / 28;
kr = kk % 28;
pow_2 = 1L << kr;
if (mm == 0)
{
m_apm_set_long(tmpN, pow_2);
m_apm_multiply(r, tmpU, tmpN);
}
else
{
m_apm_copy(tmpN, MM_One);
m_apm_set_long(tmpM, 0x10000000L); /* 2 ^ 28 */
while (TRUE)
{
m_apm_multiply(tmpT, tmpN, tmpM);
m_apm_copy(tmpN, tmpT);
if (--mm == 0)
break;
}
if (kr == 0)
{
m_apm_multiply(r, tmpU, tmpN);
}
else
{
m_apm_set_long(tmpM, pow_2);
m_apm_multiply(tmpT, tmpN, tmpM);
m_apm_multiply(r, tmpU, tmpT);
}
}
}
}
M_restore_stack(5);
}
void M_apm_sdivide(M_APM r, int places, M_APM a, M_APM b)
{
int j, k, m, b0, sign, nexp, indexr, icompare, iterations;
long trial_numer;
void *vp;
if (M_div_firsttime)
{
M_div_firsttime = FALSE;
M_div_worka = m_apm_init();
M_div_workb = m_apm_init();
M_div_tmp7 = m_apm_init();
M_div_tmp8 = m_apm_init();
M_div_tmp9 = m_apm_init();
}
sign = a->m_apm_sign * b->m_apm_sign;
if (sign == 0) /* one number is zero, result is zero */
{
if (b->m_apm_sign == 0)
{
M_apm_log_error_msg(M_APM_RETURN, "\'M_apm_sdivide\', Divide by 0");
}
M_set_to_zero(r);
return;
}
/*
* Knuth step D1. Since base = 100, base / 2 = 50.
* (also make the working copies positive)
*/
if (b->m_apm_data[0] >= 50)
{
m_apm_absolute_value(M_div_worka, a);
m_apm_absolute_value(M_div_workb, b);
}
else /* 'normal' step D1 */
{
k = 100 / (b->m_apm_data[0] + 1);
m_apm_set_long(M_div_tmp9, (long)k);
m_apm_multiply(M_div_worka, M_div_tmp9, a);
m_apm_multiply(M_div_workb, M_div_tmp9, b);
M_div_worka->m_apm_sign = 1;
M_div_workb->m_apm_sign = 1;
}
/* setup trial denominator for step D3 */
b0 = 100 * (int)M_div_workb->m_apm_data[0];
if (M_div_workb->m_apm_datalength >= 3)
b0 += M_div_workb->m_apm_data[1];
nexp = M_div_worka->m_apm_exponent - M_div_workb->m_apm_exponent;
if (nexp > 0)
iterations = nexp + places + 1;
else
iterations = places + 1;
k = (iterations + 1) >> 1; /* required size of result, in bytes */
if (k > r->m_apm_malloclength)
{
if ((vp = MAPM_REALLOC(r->m_apm_data, (k + 32))) == NULL)
{
/* fatal, this does not return */
M_apm_log_error_msg(M_APM_FATAL, "\'M_apm_sdivide\', Out of memory");
}
r->m_apm_malloclength = k + 28;
r->m_apm_data = (UCHAR *)vp;
}
/* clear the exponent in the working copies */
M_div_worka->m_apm_exponent = 0;
M_div_workb->m_apm_exponent = 0;
/* if numbers are equal, ratio == 1.00000... */
if ((icompare = m_apm_compare(M_div_worka, M_div_workb)) == 0)
{
iterations = 1;
r->m_apm_data[0] = 10;
nexp++;
}
else /* ratio not 1, do the real division */
{
if (icompare == 1) /* numerator > denominator */
{
nexp++; /* to adjust the final exponent */
M_div_worka->m_apm_exponent += 1; /* multiply numerator by 10 */
}
else /* numerator < denominator */
{
M_div_worka->m_apm_exponent += 2; /* multiply numerator by 100 */
}
indexr = 0;
m = 0;
while (TRUE)
{
/*
* Knuth step D3. Only use the 3rd -> 6th digits if the number
* actually has that many digits.
*/
trial_numer = 10000L * (long)M_div_worka->m_apm_data[0];
if (M_div_worka->m_apm_datalength >= 5)
{
trial_numer += 100 * M_div_worka->m_apm_data[1]
+ M_div_worka->m_apm_data[2];
}
else
{
if (M_div_worka->m_apm_datalength >= 3)
trial_numer += 100 * M_div_worka->m_apm_data[1];
}
j = (int)(trial_numer / b0);
/*
* Since the library 'normalizes' all the results, we need
* to look at the exponent of the number to decide if we
* have a lead in 0n or 00.
*/
if ((k = 2 - M_div_worka->m_apm_exponent) > 0)
{
while (TRUE)
{
j /= 10;
if (--k == 0)
break;
}
}
if (j == 100) /* qhat == base ?? */
j = 99; /* if so, decrease by 1 */
m_apm_set_long(M_div_tmp8, (long)j);
m_apm_multiply(M_div_tmp7, M_div_tmp8, M_div_workb);
/*
* Compare our q-hat (j) against the desired number.
* j is either correct, 1 too large, or 2 too large
* per Theorem B on pg 272 of Art of Compter Programming,
* Volume 2, 3rd Edition.
*
* The above statement is only true if using the 2 leading
* digits of the numerator and the leading digit of the
* denominator. Since we are using the (3) leading digits
* of the numerator and the (2) leading digits of the
* denominator, we eliminate the case where our q-hat is
* 2 too large, (and q-hat being 1 too large is quite remote).
*/
if (m_apm_compare(M_div_tmp7, M_div_worka) == 1)
{
j--;
m_apm_subtract(M_div_tmp8, M_div_tmp7, M_div_workb);
m_apm_copy(M_div_tmp7, M_div_tmp8);
}
/*
* Since we know q-hat is correct, step D6 is unnecessary.
*
* Store q-hat, step D5. Since D6 is unnecessary, we can
* do D5 before D4 and decide if we are done.
*/
r->m_apm_data[indexr++] = (UCHAR)j; /* j == 'qhat' */
m += 2;
if (m >= iterations)
break;
/* step D4 */
m_apm_subtract(M_div_tmp9, M_div_worka, M_div_tmp7);
/*
* if the subtraction yields zero, the division is exact
* and we are done early.
*/
if (M_div_tmp9->m_apm_sign == 0)
{
iterations = m;
break;
}
/* multiply by 100 and re-save */
M_div_tmp9->m_apm_exponent += 2;
m_apm_copy(M_div_worka, M_div_tmp9);
}
}
r->m_apm_sign = sign;
r->m_apm_exponent = nexp;
r->m_apm_datalength = iterations;
M_apm_normalize(r);
}
