BSD 4_3 release

[unix-history] / usr / contrib / apl / src / ak.c

static char Sccsid[] = "ak.c @(#)ak.c   1.1     10/1/82 Berkeley ";
#include "apl.h"

ex_scn0()
{
       fetch1();
       scan0(0);
}

ex_scan()
{
       register struct item *p;

       p = fetch1();
       scan0(p->rank-1);
}

ex_scnk()
{
       register i;

       i = topfix() - thread.iorg;
       scan0(i);
}

scan0(k)
{
       register struct item *p, *q;
       data *param[2];
       int scan1();

       p = fetch1();
       if(p->type != DA)
               error("scan T");

       bidx(p);
       colapse(k);
       if(idx.dimk == 0) {
/*
*  scan identities - ets/jrl 5/76
*/
               q = newdat(DA,0,1);
               q->dim[0] = 1;
               switch(*pcp++) {
       case ADD:
       case SUB:
       case OR:
                       q->datap[0] = 0;
                       break;
       case AND:
       case MUL:
       case DIV:
                       q->datap[0] = 1;
                       break;
       case MIN:
                       q->datap[0] = 1.0e38;
                       break;
       case MAX:
                       q->datap[0] = -1.0e38;
                       break;
       default:
                       error("reduce identity");
               }
               pop();
               *sp++ = q;
               return;
       }
       param[0] = p->datap;
       param[1] = (data *)exop[*pcp++];
       forloop(scan1, param);
}

scan1(param)
data *param[];
{
       register i;
       register data *dp;
       data d;
       data (*f)();

       dp = param[0];
       f = (data (*)())param[1];
       dp += access();
       d = *dp;
       for(i = 1; i < idx.dimk; i++) {
               dp += idx.delk;
               *dp = d = (*f)(*dp, d);
       }
}

data scalex = 453.;
data scaley = 453.;
data origx = 0.0;
data origy = 0.0;

ex_plot()
{
       register struct item *p;
       register data *dp;
       register i;
       int ic;
       int x, y;

       p = fetch1();
       if(p->type != DA)
               error("plot T");
       if(p->rank != 2)
               error("plot R");
       if(p->dim[1] != 2)
               error("plot C");

       dp = p->datap;
       if ((i = p->dim[0]) == 0) return;
       ic=0;
       while(i--) {
               x = scalex*(*dp++ - origx);
               y = 454-(scaley*(*dp++ - origy));
               if(x<0 || x >= 576 ||
                y<0 || y>=454)
                       error("plot off screen");
               if(ic)
                       line(x,y);
               else {
                       move(x,y);
                       ic=1;
               }
       }
}
line(x,y)
{
}
move(x,y)
{
}