196 lines
2.3 KiB
C++
196 lines
2.3 KiB
C++
#include "stdafx.h"
|
|
|
|
#include "defs.h"
|
|
|
|
static void __cosine(void);
|
|
static void expcos(void);
|
|
|
|
void
|
|
eval_cos(void)
|
|
{
|
|
push(cadr(p1));
|
|
eval();
|
|
cosine();
|
|
}
|
|
|
|
void
|
|
cosine(void)
|
|
{
|
|
save();
|
|
__cosine();
|
|
restore();
|
|
}
|
|
|
|
static void
|
|
__cosine(void)
|
|
{
|
|
int n;
|
|
double d;
|
|
|
|
p1 = pop();
|
|
|
|
if (p1->k == DOUBLE) {
|
|
d = cos(p1->u.d);
|
|
if (fabs(d) < 1e-10)
|
|
d = 0.0;
|
|
push_double(d);
|
|
return;
|
|
}
|
|
|
|
if (expomode == 1) {
|
|
push(p1);
|
|
expcos();
|
|
return;
|
|
}
|
|
|
|
// multiply by 180/pi
|
|
|
|
push(p1);
|
|
push_integer(180);
|
|
multiply();
|
|
push_symbol(PI);
|
|
divide();
|
|
|
|
n = pop_integer();
|
|
|
|
if (n == (int) 0x80000000) {
|
|
push_symbol(COS);
|
|
push(p1);
|
|
list(2);
|
|
return;
|
|
}
|
|
|
|
if (n < 0)
|
|
n = -n;
|
|
|
|
switch (n % 360) {
|
|
case 0:
|
|
push_integer(1);
|
|
break;
|
|
case 60:
|
|
push_rational(1, 2);
|
|
break;
|
|
case 90:
|
|
push_integer(0);
|
|
break;
|
|
case 120:
|
|
push_rational(-1, 2);
|
|
break;
|
|
case 180:
|
|
push_integer(-1);
|
|
break;
|
|
case 240:
|
|
push_rational(-1, 2);
|
|
break;
|
|
case 270:
|
|
push_integer(0);
|
|
break;
|
|
case 300:
|
|
push_rational(1, 2);
|
|
break;
|
|
default:
|
|
push_symbol(COS);
|
|
push(p1);
|
|
list(2);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void
|
|
expcos(void)
|
|
{
|
|
save();
|
|
p1 = pop();
|
|
|
|
push(unit_imaginary);
|
|
push(p1);
|
|
multiply();
|
|
exponential();
|
|
push_integer(2);
|
|
divide();
|
|
|
|
push(unit_imaginary);
|
|
negate();
|
|
push(p1);
|
|
multiply();
|
|
exponential();
|
|
push_integer(2);
|
|
divide();
|
|
|
|
add();
|
|
|
|
restore();
|
|
}
|
|
|
|
static char *s[] = {
|
|
|
|
"expomode=0",
|
|
"",
|
|
|
|
"cos(-pi)", // -180 degrees
|
|
"-1",
|
|
|
|
"cos(-5/6*pi)", // -150 degrees
|
|
"cos(-5/6*pi)",
|
|
|
|
"cos(-3/4*pi)", // -135 degrees
|
|
"cos(-3/4*pi)",
|
|
|
|
"cos(-pi*2/3)", // -120 degrees
|
|
"-1/2",
|
|
|
|
"cos(-pi/2)", // -90 degrees
|
|
"0",
|
|
|
|
"cos(-pi/3)", // -60 degrees
|
|
"1/2",
|
|
|
|
"cos(-1/4*pi)", // -45 degrees
|
|
"cos(-1/4*pi)",
|
|
|
|
"cos(-1/6*pi)", // -30 degrees
|
|
"cos(-1/6*pi)",
|
|
|
|
"cos(0)", // 0 degrees
|
|
"1",
|
|
|
|
"cos(1/6*pi)", // 30 degrees
|
|
"cos(1/6*pi)",
|
|
|
|
"cos(1/4*pi)", // 45 degrees
|
|
"cos(1/4*pi)",
|
|
|
|
"cos(pi/3)", // 60 degrees
|
|
"1/2",
|
|
|
|
"cos(pi/2)", // 90 degrees
|
|
"0",
|
|
|
|
"cos(pi*2/3)", // 120 degrees
|
|
"-1/2",
|
|
|
|
"cos(3/4*pi)", // 135 degrees
|
|
"cos(3/4*pi)",
|
|
|
|
"cos(5/6*pi)", // 150 degrees
|
|
"cos(5/6*pi)",
|
|
|
|
"cos(pi)", // 180 degrees
|
|
"-1",
|
|
|
|
"expomode=1",
|
|
"",
|
|
|
|
"cos(x)",
|
|
"1/2*exp(-i*x)+1/2*exp(i*x)",
|
|
|
|
"expomode=0",
|
|
"",
|
|
};
|
|
|
|
void
|
|
test_cos(void)
|
|
{
|
|
test(__FILE__, s, sizeof s / sizeof (char *));
|
|
}
|