void
add_numbers(void)
{
double a, b;
if (isrational(stack[tos - 1]) && isrational(stack[tos - 2])) {
qadd();
return;
}
save();
p2 = pop();
p1 = pop();
if (isdouble(p1))
a = p1->u.d;
else
a = convert_rational_to_double(p1);
if (isdouble(p2))
b = p2->u.d;
else
b = convert_rational_to_double(p2);
push_double(a + b);
restore();
}
void
divide_numbers(void)
{
double a, b;
if (isrational(stack[tos - 1]) && isrational(stack[tos - 2])) {
qdiv();
return;
}
save();
p2 = pop();
p1 = pop();
if (iszero(p2))
stop("divide by zero");
if (isdouble(p1))
a = p1->u.d;
else
a = convert_rational_to_double(p1);
if (isdouble(p2))
b = p2->u.d;
else
b = convert_rational_to_double(p2);
push_double(a / b);
restore();
}
int
compare_numbers(U *a, U *b)
{
double x, y;
if (isrational(a) && isrational(b))
return compare_rationals(a, b);
if (isdouble(a))
x = a->u.d;
else
x = convert_rational_to_double(a);
if (isdouble(b))
y = b->u.d;
else
y = convert_rational_to_double(b);
if (x < y)
return -1;
if (x > y)
return 1;
return 0;
}
void
yypower(void)
{
int n;
p2 = pop();
p1 = pop();
// both base and exponent are rational numbers?
if (isrational(p1) && isrational(p2)) {
push(p1);
push(p2);
qpow();
return;
}
// both base and exponent are either rational or double?
if (isnum(p1) && isnum(p2)) {
push(p1);
push(p2);
dpow();
return;
}
if (istensor(p1)) {
power_tensor();
return;
}
if (p1 == symbol(E) && car(p2) == symbol(LOG)) {
push(cadr(p2));
return;
}
if (p1 == symbol(E) && isdouble(p2)) {
push_double(exp(p2->u.d));
return;
}
// 1 ^ a -> 1
// a ^ 0 -> 1
if (equal(p1, one) || iszero(p2)) {
push(one);
return;
}
// a ^ 1 -> a
if (equal(p2, one)) {
push(p1);
return;
}
// (a * b) ^ c -> (a ^ c) * (b ^ c)
if (car(p1) == symbol(MULTIPLY)) {
p1 = cdr(p1);
push(car(p1));
push(p2);
power();
p1 = cdr(p1);
while (iscons(p1)) {
push(car(p1));
push(p2);
power();
multiply();
p1 = cdr(p1);
}
return;
}
// (a ^ b) ^ c -> a ^ (b * c)
if (car(p1) == symbol(POWER)) {
push(cadr(p1));
push(caddr(p1));
push(p2);
multiply();
power();
return;
}
// (a + b) ^ n -> (a + b) * (a + b) ...
if (expanding && isadd(p1) && isnum(p2)) {
push(p2);
n = pop_integer();
// this && n != 0x80000000 added by DDC
// as it's not always the case that 0x80000000
// is negative
if (n > 1 && n != 0x80000000) {
power_sum(n);
return;
}
}
// sin(x) ^ 2n -> (1 - cos(x) ^ 2) ^ n
if (trigmode == 1 && car(p1) == symbol(SIN) && iseveninteger(p2)) {
push_integer(1);
push(cadr(p1));
cosine();
push_integer(2);
power();
subtract();
push(p2);
push_rational(1, 2);
multiply();
power();
return;
}
// cos(x) ^ 2n -> (1 - sin(x) ^ 2) ^ n
if (trigmode == 2 && car(p1) == symbol(COS) && iseveninteger(p2)) {
push_integer(1);
push(cadr(p1));
sine();
push_integer(2);
power();
subtract();
push(p2);
push_rational(1, 2);
multiply();
power();
return;
}
// complex number? (just number, not expression)
if (iscomplexnumber(p1)) {
// integer power?
// n will be negative here, positive n already handled
if (isinteger(p2)) {
// / \ n
// -n | a - ib |
// (a + ib) = | -------- |
// | 2 2 |
// \ a + b /
push(p1);
conjugate();
p3 = pop();
push(p3);
push(p3);
push(p1);
multiply();
divide();
push(p2);
negate();
power();
return;
}
// noninteger or floating power?
if (isnum(p2)) {
#if 1 // use polar form
push(p1);
mag();
push(p2);
power();
push_integer(-1);
push(p1);
arg();
push(p2);
multiply();
push(symbol(PI));
divide();
power();
multiply();
#else // use exponential form
push(p1);
mag();
push(p2);
power();
push(symbol(E));
push(p1);
arg();
push(p2);
multiply();
push(imaginaryunit);
multiply();
power();
multiply();
#endif
return;
}
}
if (simplify_polar())
return;
push_symbol(POWER);
push(p1);
push(p2);
list(3);
}
