Mathc initiation/a296

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	kg_r.h

/* --------------------------------- */
/* save as kg_r.h                    */
/* --------------------------------- */
void   G_r(
CTRL_splot w,
double ax,
double bx,
pt2d    d,
double step,
double (*P_v)(double x)
)
{
double  t;
double  i;
 
FILE   *fp = fopen("a_main.plt","w");

 fprintf(fp," set zeroaxis lt 8\n" 
            " set grid\n\n" 
            " plot [%0.3f:%0.3f] [%0.3f:%0.3f]\\\n"
            " \"ab\"   with line lt 7 lw 2,\\\n" 
            " \"a_r\"  with line lt 9 lw 2,\\\n" 
            " \"dxdy\" with line lt 9 lw 2,\\\n" 
            " \"vx\"   with line lt 7 lw 2   \n"
            " reset\n\n",
              w.xmin,w.xmax,w.ymin,w.ymax);
  fclose(fp);

 fp = fopen("ab",  "w");
 fprintf(fp," %0.6f   %0.6f  \n", ax, ((*P_v)(ax)));
 fprintf(fp," %0.6f   %0.6f\n\n", ax,          0.0); 
 fprintf(fp," %0.6f   %0.6f  \n", bx, ((*P_v)(bx)));
 fprintf(fp," %0.6f   %0.6f  \n", bx,          0.0);
  fclose(fp);
  
 fp = fopen("a_r",  "w");
   t = ((ax+bx)/2.);
 fprintf(fp," %0.6f   %0.6f\n", t-(d.x), (*P_v)(t));
 fprintf(fp," %0.6f   %0.6f\n", t-(d.x),       0.0);
 fprintf(fp," %0.6f   %0.6f\n", t+(d.x),       0.0);
 fprintf(fp," %0.6f   %0.6f\n", t+(d.x), (*P_v)(t));
 fprintf(fp," %0.6f   %0.6f\n", t-(d.x), (*P_v)(t));
  fclose(fp);

 fp = fopen("dxdy",  "w");
   t = ((ax+bx)/2.);
 fprintf(fp," %0.6f   %0.6f\n", t-(d.x),  (*P_v)(t/2)     );
 fprintf(fp," %0.6f   %0.6f\n", t-(d.x),  (*P_v)(t/2-3*d.y));
 fprintf(fp," %0.6f   %0.6f\n", t+(d.x),  (*P_v)(t/2-3*d.y));
 fprintf(fp," %0.6f   %0.6f\n", t+(d.x),  (*P_v)(t/2)      );
 fprintf(fp," %0.6f   %0.6f\n", t-(d.x),  (*P_v)(t/2)      );
  fclose(fp);

 fp = fopen("vx",  "w");
   i = ax;
   do{
      fprintf(fp," %0.6f   %0.6f\n", i, ((*P_v)(i)));
      i += step;
   }while(i <=  bx);
  fclose(fp);
             
   printf(" ... load \"a_main.plt\" ... with gnuplot.\n\n");
}
/* --------------------------------- */
/* --------------------------------- */

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