eigenmath/abs.cpp
2005-08-06 13:57:37 -07:00

121 lines
1.3 KiB
C++

#include "stdafx.h"
#include "defs.h"
extern void conjugate(void);
extern int isnegativeterm(U *);
static void yabsval(void);
static void absval_tensor(void);
void
eval_abs(void)
{
push(cadr(p1));
eval();
absval();
}
void
absval(void)
{
save();
yabsval();
restore();
}
static void
yabsval(void)
{
p1 = pop();
if (istensor(p1)) {
absval_tensor();
return;
}
if (isnum(p1)) {
push(p1);
if (isnegativenumber(p1))
negate();
return;
}
if (iscomplexnumber(p1)) {
push(p1);
push(p1);
conjugate();
multiply();
push_rational(1, 2);
power();
return;
}
if (isnegativeterm(p1) || (car(p1) == symbol(ADD) && isnegativeterm(cadr(p1)))) {
push(p1);
negate();
p1 = pop();
}
push_symbol(ABS);
push(p1);
list(2);
}
static void
absval_tensor(void)
{
if (p1->u.tensor->ndim != 1)
stop("abs(tensor) with tensor rank > 1");
push(p1);
push(p1);
conjugate();
inner();
push_rational(1, 2);
power();
}
static char *s[] = {
"abs(2)",
"2",
"abs(2.0)",
"2",
"abs(-2)",
"2",
"abs(-2.0)",
"2",
"abs(a)",
"abs(a)",
"abs(-a)",
"abs(a)",
"abs(2*a)",
"abs(2*a)",
"abs(-2*a)",
"abs(2*a)",
"abs(2.0*a)",
"abs(2*a)",
"abs(-2.0*a)",
"abs(2*a)",
"abs(a-b)+abs(b-a)",
"2*abs(a-b)",
"abs(3 + 4 i)",
"5",
"abs((2,3,4))",
"29^(1/2)",
};
void
test_abs(void)
{
test(__FILE__, s, sizeof s / sizeof (char *));
}