Graphics Plus/Graphics Plus.iso/amiga/plotting/gnuplot3.lzh/gnuplot/internal.c

C/C++ Source or Header | 1991-08-22 | 16KB | 859 lines

/* GNUPLOT - internal.c */
/*
 * Copyright (C) 1986, 1987, 1990, 1991   Thomas Williams, Colin Kelley
 *
 * Permission to use, copy, and distribute this software and its
 * documentation for any purpose with or without fee is hereby granted,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.
 *
 * Permission to modify the software is granted, but not the right to
 * distribute the modified code.  Modifications are to be distributed
 * as patches to released version.
 *
 * This software is provided "as is" without express or implied warranty.
 *
 *
 * AUTHORS
 *
 *   Original Software:
 *     Thomas Williams,  Colin Kelley.
 *
 *   Gnuplot 2.0 additions:
 *       Russell Lang, Dave Kotz, John Campbell.
 *
 *   Gnuplot 3.0 additions:
 *       Gershon Elber and many others.
 *
 * Send your comments or suggestions to
 *  pixar![e-mail].
 * This is a mailing list; to join it send a note to
 *  pixar![e-mail].
 * Send bug reports to
 *  pixar![e-mail].
 */

#include <math.h>
#include <stdio.h>
#include "plot.h"

BOOLEAN undefined;

char *strcpy();

struct value *pop(), *complex(), *integer();
double magnitude(), angle(), real();

struct value stack[STACK_DEPTH];

int s_p = -1;   /* stack pointer */


/*
 * System V and MSC 4.0 call this when they wants to print an error message.
 * Don't!
 */
#ifdef MSDOS
#ifdef __TURBOC__
int matherr()    /* Turbo C */
#else
int matherr(x)    /* MSC 5.1 */
struct exception *x;
#endif /* TURBOC */
#else /* not MSDOS */
#ifdef apollo
int matherr(struct exception *x)    /* apollo */
#else /* apollo */
#ifdef AMIGA_LC_5_1
int matherr(x)    /* AMIGA_LC_5_1 */
struct exception *x;
#else    /* Most everyone else (not apollo). */
int matherr()
#endif /* AMIGA_LC_5_1 */
#endif /* apollo */
#endif /* MSDOS */
{
    return (undefined = TRUE);        /* don't print error message */
}


reset_stack()
{
    s_p = -1;
}


check_stack()    /* make sure stack's empty */
{
    if (s_p != -1)
        fprintf(stderr,"\nwarning:  internal error--stack not empty!\n");
}


struct value *pop(x)
struct value *x;
{
    if (s_p  < 0 )
        int_error("stack underflow",NO_CARET);
    *x = stack[s_p--];
    return(x);
}


push(x)
struct value *x;
{
    if (s_p == STACK_DEPTH - 1)
        int_error("stack overflow",NO_CARET);
    stack[++s_p] = *x;
}


#define ERR_VAR "undefined variable: "

f_push(x)
union argument *x;        /* contains pointer to value to push; */
{
static char err_str[sizeof(ERR_VAR) + MAX_ID_LEN] = ERR_VAR;
struct udvt_entry *udv;

    udv = x->udv_arg;
    if (udv->udv_undef) {     /* undefined */
        (void) strcpy(&err_str[sizeof(ERR_VAR) - 1], udv->udv_name);
        int_error(err_str,NO_CARET);
    }
    push(&(udv->udv_value));
}


f_pushc(x)
union argument *x;
{
    push(&(x->v_arg));
}


f_pushd1(x)
union argument *x;
{
    push(&(x->udf_arg->dummy_values[0]));
}


f_pushd2(x)
union argument *x;
{
    push(&(x->udf_arg->dummy_values[1]));
}


#define ERR_FUN "undefined function: "

f_call(x)  /* execute a udf */
union argument *x;
{
static char err_str[sizeof(ERR_FUN) + MAX_ID_LEN] = ERR_FUN;
register struct udft_entry *udf;
struct value save_dummy;

    udf = x->udf_arg;
    if (!udf->at) { /* undefined */
        (void) strcpy(&err_str[sizeof(ERR_FUN) - 1],
                udf->udf_name);
        int_error(err_str,NO_CARET);
    }
    save_dummy = udf->dummy_values[0];
    (void) pop(&(udf->dummy_values[0]));

    execute_at(udf->at);
    udf->dummy_values[0] = save_dummy;
}

f_call2(x)  /* execute a udf of two variables */
union argument *x;
{
static char err_str[sizeof(ERR_FUN) + MAX_ID_LEN] = ERR_FUN;
register struct udft_entry *udf;
struct value save_dummy0, save_dummy1;

    udf = x->udf_arg;
    if (!udf->at) { /* undefined */
        (void) strcpy(&err_str[sizeof(ERR_FUN) - 1],
                udf->udf_name);
        int_error(err_str,NO_CARET);
    }
    save_dummy1 = udf->dummy_values[1];
    save_dummy0 = udf->dummy_values[0];
    (void) pop(&(udf->dummy_values[1]));
    (void) pop(&(udf->dummy_values[0]));

    execute_at(udf->at);
    udf->dummy_values[1] = save_dummy1;
    udf->dummy_values[0] = save_dummy0;
}


static int_check(v)
struct value *v;
{
    if (v->type != INT)
        int_error("non-integer passed to boolean operator",NO_CARET);
}


f_lnot()
{
struct value a;
    int_check(pop(&a));
    push(integer(&a,!a.v.int_val) );
}


f_bnot()
{
struct value a;
    int_check(pop(&a));
    push( integer(&a,~a.v.int_val) );
}


f_bool()
{            /* converts top-of-stack to boolean */
    int_check(&top_of_stack);
    top_of_stack.v.int_val = !!top_of_stack.v.int_val;
}


f_lor()
{
struct value a,b;
    int_check(pop(&b));
    int_check(pop(&a));
    push( integer(&a,a.v.int_val || b.v.int_val) );
}

f_land()
{
struct value a,b;
    int_check(pop(&b));
    int_check(pop(&a));
    push( integer(&a,a.v.int_val && b.v.int_val) );
}


f_bor()
{
struct value a,b;
    int_check(pop(&b));
    int_check(pop(&a));
    push( integer(&a,a.v.int_val | b.v.int_val) );
}


f_xor()
{
struct value a,b;
    int_check(pop(&b));
    int_check(pop(&a));
    push( integer(&a,a.v.int_val ^ b.v.int_val) );
}


f_band()
{
struct value a,b;
    int_check(pop(&b));
    int_check(pop(&a));
    push( integer(&a,a.v.int_val & b.v.int_val) );
}


f_uminus()
{
struct value a;
    (void) pop(&a);
    switch(a.type) {
        case INT:
            a.v.int_val = -a.v.int_val;
            break;
        case CMPLX:
            a.v.cmplx_val.real =
                -a.v.cmplx_val.real;
            a.v.cmplx_val.imag =
                -a.v.cmplx_val.imag;
    }
    push(&a);
}


f_eq() /* note: floating point equality is rare because of roundoff error! */
{
struct value a, b;
    register int result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    result = (a.v.int_val ==
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.int_val ==
                        b.v.cmplx_val.real &&
                       b.v.cmplx_val.imag == 0.0);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    result = (b.v.int_val == a.v.cmplx_val.real &&
                       a.v.cmplx_val.imag == 0.0);
                    break;
                case CMPLX:
                    result = (a.v.cmplx_val.real==
                        b.v.cmplx_val.real &&
                        a.v.cmplx_val.imag==
                        b.v.cmplx_val.imag);
            }
    }
    push(integer(&a,result));
}


f_ne()
{
struct value a, b;
    register int result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    result = (a.v.int_val !=
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.int_val !=
                        b.v.cmplx_val.real ||
                       b.v.cmplx_val.imag != 0.0);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    result = (b.v.int_val !=
                        a.v.cmplx_val.real ||
                       a.v.cmplx_val.imag != 0.0);
                    break;
                case CMPLX:
                    result = (a.v.cmplx_val.real !=
                        b.v.cmplx_val.real ||
                        a.v.cmplx_val.imag !=
                        b.v.cmplx_val.imag);
            }
    }
    push(integer(&a,result));
}


f_gt()
{
struct value a, b;
    register int result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    result = (a.v.int_val >
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.int_val >
                        b.v.cmplx_val.real);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    result = (a.v.cmplx_val.real >
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.cmplx_val.real >
                        b.v.cmplx_val.real);
            }
    }
    push(integer(&a,result));
}


f_lt()
{
struct value a, b;
    register int result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    result = (a.v.int_val <
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.int_val <
                        b.v.cmplx_val.real);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    result = (a.v.cmplx_val.real <
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.cmplx_val.real <
                        b.v.cmplx_val.real);
            }
    }
    push(integer(&a,result));
}


f_ge()
{
struct value a, b;
    register int result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    result = (a.v.int_val >=
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.int_val >=
                        b.v.cmplx_val.real);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    result = (a.v.cmplx_val.real >=
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.cmplx_val.real >=
                        b.v.cmplx_val.real);
            }
    }
    push(integer(&a,result));
}


f_le()
{
struct value a, b;
    register int result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    result = (a.v.int_val <=
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.int_val <=
                        b.v.cmplx_val.real);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    result = (a.v.cmplx_val.real <=
                        b.v.int_val);
                    break;
                case CMPLX:
                    result = (a.v.cmplx_val.real <=
                        b.v.cmplx_val.real);
            }
    }
    push(integer(&a,result));
}


f_plus()
{
struct value a, b, result;
    (void) pop(&b);
    (void) pop(&a);
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    (void) integer(&result,a.v.int_val +
                        b.v.int_val);
                    break;
                case CMPLX:
                    (void) complex(&result,a.v.int_val +
                        b.v.cmplx_val.real,
                       b.v.cmplx_val.imag);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    (void) complex(&result,b.v.int_val +
                        a.v.cmplx_val.real,
                       a.v.cmplx_val.imag);
                    break;
                case CMPLX:
                    (void) complex(&result,a.v.cmplx_val.real+
                        b.v.cmplx_val.real,
                        a.v.cmplx_val.imag+
                        b.v.cmplx_val.imag);
            }
    }
    push(&result);
}


f_minus()
{
struct value a, b, result;
    (void) pop(&b);
    (void) pop(&a);        /* now do a - b */
    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    (void) integer(&result,a.v.int_val -
                        b.v.int_val);
                    break;
                case CMPLX:
                    (void) complex(&result,a.v.int_val -
                        b.v.cmplx_val.real,
                       -b.v.cmplx_val.imag);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    (void) complex(&result,a.v.cmplx_val.real -
                        b.v.int_val,
                        a.v.cmplx_val.imag);
                    break;
                case CMPLX:
                    (void) complex(&result,a.v.cmplx_val.real-
                        b.v.cmplx_val.real,
                        a.v.cmplx_val.imag-
                        b.v.cmplx_val.imag);
            }
    }
    push(&result);
}


f_mult()
{
struct value a, b, result;
    (void) pop(&b);
    (void) pop(&a);    /* now do a*b */

    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    (void) integer(&result,a.v.int_val *
                        b.v.int_val);
                    break;
                case CMPLX:
                    (void) complex(&result,a.v.int_val *
                        b.v.cmplx_val.real,
                        a.v.int_val *
                        b.v.cmplx_val.imag);
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    (void) complex(&result,b.v.int_val *
                        a.v.cmplx_val.real,
                        b.v.int_val *
                        a.v.cmplx_val.imag);
                    break;
                case CMPLX:
                    (void) complex(&result,a.v.cmplx_val.real*
                        b.v.cmplx_val.real-
                        a.v.cmplx_val.imag*
                        b.v.cmplx_val.imag,
                        a.v.cmplx_val.real*
                        b.v.cmplx_val.imag+
                        a.v.cmplx_val.imag*
                        b.v.cmplx_val.real);
            }
    }
    push(&result);
}


f_div()
{
struct value a, b, result;
register double square;
    (void) pop(&b);
    (void) pop(&a);    /* now do a/b */

    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    if (b.v.int_val)
                      (void) integer(&result,a.v.int_val /
                        b.v.int_val);
                    else {
                      (void) integer(&result,0);
                      undefined = TRUE;
                    }
                    break;
                case CMPLX:
                    square = b.v.cmplx_val.real*
                        b.v.cmplx_val.real +
                        b.v.cmplx_val.imag*
                        b.v.cmplx_val.imag;
                    if (square)
                        (void) complex(&result,a.v.int_val*
                        b.v.cmplx_val.real/square,
                        -a.v.int_val*
                        b.v.cmplx_val.imag/square);
                    else {
                        (void) complex(&result,0.0,0.0);
                        undefined = TRUE;
                    }
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    if (b.v.int_val)

                      (void) complex(&result,a.v.cmplx_val.real/
                        b.v.int_val,
                        a.v.cmplx_val.imag/
                        b.v.int_val);
                    else {
                        (void) complex(&result,0.0,0.0);
                        undefined = TRUE;
                    }
                    break;
                case CMPLX:
                    square = b.v.cmplx_val.real*
                        b.v.cmplx_val.real +
                        b.v.cmplx_val.imag*
                        b.v.cmplx_val.imag;
                    if (square)
                    (void) complex(&result,(a.v.cmplx_val.real*
                        b.v.cmplx_val.real+
                        a.v.cmplx_val.imag*
                        b.v.cmplx_val.imag)/square,
                        (a.v.cmplx_val.imag*
                        b.v.cmplx_val.real-
                        a.v.cmplx_val.real*
                        b.v.cmplx_val.imag)/
                            square);
                    else {
                        (void) complex(&result,0.0,0.0);
                        undefined = TRUE;
                    }
            }
    }
    push(&result);
}


f_mod()
{
struct value a, b;
    (void) pop(&b);
    (void) pop(&a);    /* now do a%b */

    if (a.type != INT || b.type != INT)
        int_error("can only mod ints",NO_CARET);
    if (b.v.int_val)
        push(integer(&a,a.v.int_val % b.v.int_val));
    else {
        push(integer(&a,0));
        undefined = TRUE;
    }
}


f_power()
{
struct value a, b, result;
register int i, t, count;
register double mag, ang;
    (void) pop(&b);
    (void) pop(&a);    /* now find a**b */

    switch(a.type) {
        case INT:
            switch (b.type) {
                case INT:
                    count = abs(b.v.int_val);
                    t = 1;
                    for(i = 0; i < count; i++)
                        t *= a.v.int_val;
                    if (b.v.int_val >= 0)
                        (void) integer(&result,t);
                    else
                      if (t != 0)
                        (void) complex(&result,1.0/t,0.0);
                      else {
                         undefined = TRUE;
                         (void) complex(&result, 0.0, 0.0);
                      }
                    break;
                case CMPLX:
                    mag =
                      pow(magnitude(&a),fabs(b.v.cmplx_val.real));
                    if (b.v.cmplx_val.real < 0.0)
                      if (mag != 0.0)
                        mag = 1.0/mag;
                      else
                        undefined = TRUE;
                    mag *= exp(-b.v.cmplx_val.imag*angle(&a));
                    ang = b.v.cmplx_val.real*angle(&a) +
                          b.v.cmplx_val.imag*log(magnitude(&a));
                    (void) complex(&result,mag*cos(ang),
                        mag*sin(ang));
            }
            break;
        case CMPLX:
            switch (b.type) {
                case INT:
                    if (a.v.cmplx_val.imag == 0.0) {
                        mag = pow(a.v.cmplx_val.real,(double)abs(b.v.int_val));
                        if (b.v.int_val < 0)
                          if (mag != 0.0)
                            mag = 1.0/mag;
                          else
                            undefined = TRUE;
                        (void) complex(&result,mag,0.0);
                    }
                    else {
                        /* not so good, but...! */
                        mag = pow(magnitude(&a),(double)abs(b.v.int_val));
                        if (b.v.int_val < 0)
                          if (mag != 0.0)
                            mag = 1.0/mag;
                          else
                            undefined = TRUE;
                        ang = angle(&a)*b.v.int_val;
                        (void) complex(&result,mag*cos(ang),
                            mag*sin(ang));
                    }
                    break;
                case CMPLX:
                    mag = pow(magnitude(&a),fabs(b.v.cmplx_val.real));
                    if (b.v.cmplx_val.real < 0.0)
                      if (mag != 0.0)
                        mag = 1.0/mag;
                      else
                        undefined = TRUE;
                    mag *= exp(-b.v.cmplx_val.imag*angle(&a));
                    ang = b.v.cmplx_val.real*angle(&a) +
                          b.v.cmplx_val.imag*log(magnitude(&a));
                    (void) complex(&result,mag*cos(ang),
                        mag*sin(ang));
            }
    }
    push(&result);
}


f_factorial()
{
struct value a;
register int i;
register double val;

    (void) pop(&a);    /* find a! (factorial) */

    switch (a.type) {
        case INT:
            val = 1.0;
            for (i = a.v.int_val; i > 1; i--)  /*fpe's should catch overflows*/
                val *= i;
            break;
        default:
            int_error("factorial (!) argument must be an integer",
            NO_CARET);
        }

    push(complex(&a,val,0.0));

}


int
f_jump(x)
union argument *x;
{
    return(x->j_arg);
}


int
f_jumpz(x)
union argument *x;
{
struct value a;
    int_check(&top_of_stack);
    if (top_of_stack.v.int_val) {    /* non-zero */
        (void) pop(&a);
        return 1;                /* no jump */
    }
    else
        return(x->j_arg);        /* leave the argument on TOS */
}


int
f_jumpnz(x)
union argument *x;
{
struct value a;
    int_check(&top_of_stack);
    if (top_of_stack.v.int_val)    /* non-zero */
        return(x->j_arg);        /* leave the argument on TOS */
    else {
        (void) pop(&a);
        return 1;                /* no jump */
    }
}


int
f_jtern(x)
union argument *x;
{
struct value a;

    int_check(pop(&a));
    if (a.v.int_val)
        return(1);                /* no jump; fall through to TRUE code */
    else
        return(x->j_arg);        /* go jump to FALSE code */
}