/***************************************************************/
/**                         E X A _ C                         **/
/**                                                           **/
/** This is the C examples program for the data plotting      **/
/** library DISLIN.                                           **/
/**                                                           **/
/** Version: 10.4 / Windows                                   **/
/***************************************************************/

#include <stdio.h>
#include <math.h>                  
#include <string.h>
#include "dislin.h"

void     widget  (void);
void     mysub   (int id);
void     exa     (char *cdev, int iopt);
void     exa_1   (void);
void     exa_2   (void);
void     exa_3   (void);
void     exa_4   (void);
void     exa_5   (void);
void     exa_6   (void);
void     exa_7   (void);
void     exa_8   (void);
void     exa_9   (void);
void     exa_10  (void);
void     exa_11  (void);
void     exa12_1 (void);
void     exa_12  (void);
void     exa12_2 (void);
void     exa_13  (void);
void     exa_14  (void);
void     ex6_1   (void);
void     ex10_1  (void);
void     ex10_2  (void);
void     ex10_3  (void);
void     ex11_1  (void);
void     ex13_1  (void);
void     ex13_2  (void);
void     ex13_3  (void);
void     ex13_4  (void);
void     ex14_1  (void);
void     ex14_2  (void);
  
float    zfun    (float x, float y, int iopt);
                      
static float xray[300], yray[300], y1ray[300], y2ray[300], zmat[50][50];
static char  cl1[450], cl2[450];
static int id_lis1, id_lis2, id_pbut;

int main ()
{                                                
  widget ();
  return 0;
}

void widget ()
{ int ip, ip_l, ip_r, idev = 1, iopt = 1;
  char chelp[300];
  	
  strcpy (chelp, "C Demo program for the graphics library DISLIN.|");
  strcat (chelp, "Author: Helmut Michels,|");
  strcat (chelp, "Max-Planck-Institut fuer Sonnensystemforschung,|");
  strcat (chelp, "           D-37077 Goettingen, Germany");

  strcpy (cl1, "CONS   (X Window Screen)|");
  strcat (cl1, "XWIN   (Small Window)|");
  strcat (cl1, "GL       (OpenGL Window)|");
  strcat (cl1, "GKSL   (GKSLIN Metafile)|");
  strcat (cl1, "CGM    (CGM Metafile)|");
  strcat (cl1, "PS       (PostScript File)|");
  strcat (cl1, "EPS     (EPS File)|");
  strcat (cl1, "PDF     (PDF File)|");
  strcat (cl1, "WMF    (Windows Metafile)|");
  strcat (cl1, "HPGL   (HPGL Plotfile)|");
  strcat (cl1, "SVG     (SVG File)|");
  strcat (cl1, "JAVA   (Java Applet File)|");
  strcat (cl1, "GIF     (GIF File)|");
  strcat (cl1, "TIFF   (TIFF File)|");
  strcat (cl1, "PNG    (PNG File)|");
  strcat (cl1, "PPM    (PPM File)|");
  strcat (cl1, "BMP    (BMP File)|");
  strcat (cl1, "IMAG   (Image File)");

  strcpy (cl2, "Demo of CURVE|Polar Plots|Symbols|Logarithmic Axes|");
  strcat (cl2, "Interpolation Methods|Line Styles|Legend|");
  strcat (cl2, "Shading Patterns (AREAF)|Vectors|");
  strcat (cl2, "Shading Patterns (PIEGRF)|Surface Plot|");
  strcat (cl2, "Surface Plot|Parametric Function Plot|");
  strcat (cl2, "Map Plot|World Coastlines|");
  strcat (cl2, "Elliptical Proj.|Azimuthal Proj.|Conical Proj.|");
  strcat (cl2, "Bar Graphs|Pie Charts|3-D Bar Graph / Pie Chart|");
  strcat (cl2, "Contours|Shaded Contours|");
  strcat (cl2, "Instruction Alphabet|3-D Colour Plot|Shaded World|");
  strcat (cl2, "Colour Tables");

  swgtit ("DISLIN Examples");
  swghlp (chelp);
  swgwth (30);
  swgtyp ("SCROLL", "LIST");
  swgpop ("NOOK");
  
  ip = wgini ("hori");
  ip_l = wgbas (ip, "vert");
  ip_r = wgbas (ip, "vert");

  wglab (ip_l, "Example:");
  id_lis1 = wglis (ip_l, cl2, iopt);
  
  wglab (ip_r, "Device:");
  id_lis2 = wglis (ip_r, cl1, idev);
  
  id_pbut = wgpbut (ip_r, "Plot");
  swgcbk (id_pbut, mysub);

  wgquit (ip_l);
  wgfin ();
}  

void mysub (int id)
{ int iopt, idev;
  char cdev[5], *cstr;

  if (getlev () != 0) return;
  if (id != id_pbut) return;
  iopt = gwglis (id_lis1);
  idev = gwglis (id_lis2);

  cstr = itmstr (cl1, idev);
  strncpy (cdev, cstr, 4);
  cdev[4] = '\0';
  
  exa (cdev, iopt);
  return;
}
 
void exa (char *cdev, int iopt)
{
  metafl (cdev);
  setpag ("da4l");
  
  switch (iopt)
  { case  1: exa_1 ();
             break;
    case  2: exa_2 ();
             break;
    case  3: exa_3 ();
             break;
    case  4: exa_4 ();
             break;
    case  5: exa_5 ();
             break;
    case  6: exa_6 ();
             break;
    case  7: exa_7 ();
             break;
    case  8: exa_8 ();
             break;
    case  9: exa_9 ();
             break;
    case 10: exa_10 ();
             break;
    case 11: exa_11 ();
             break;
    case 12: exa12_1 ();
             break;
    case 13: exa12_2 ();
             break;
    case 14: exa_12 ();
             break;
    case 15: ex13_1 ();
             break;
    case 16: ex13_2 ();
             break;
    case 17: ex13_3 ();
             break;
    case 18: ex13_4 ();
             break;
    case 19: ex10_1 ();
             break;
    case 20: ex10_2 ();
             break;
    case 21: ex10_3 ();
             break;
    case 22: ex14_1 ();
             break;
    case 23: ex14_2 ();
             break;
    case 24: ex6_1 ();
             break;
    case 25: ex11_1 ();
             break;
    case 26: exa_13 ();
             break;
    case 27: exa_14 ();
             break;
  }
}

/* >>>>>>>>>> EXA_1  <<<<<<<<<< */
void exa_1 (void)
{ int n = 100, i;
  double fpi = 3.1415926 / 180., step, x;

  step = 360. / (n-1);

  for (i = 0; i < n; i++)
  { xray[i] = (float) (i * step);
    x = xray[i] * fpi;
    y1ray[i] = (float) sin (x);
    y2ray[i] = (float) cos (x);
  }

  disini ();
  pagera ();
  hwfont ();
  axspos (450, 1800);
  axslen (2200, 1200);

  name   ("X-axis", "x");
  name   ("Y-axis", "y");

  labdig (-1, "x");
  ticks  (10, "xy");

  titlin ("Demonstration of CURVE", 1);
  titlin ("SIN(X), COS(X)", 3);

  graf   (0.f, 360.f, 0.f, 90.f, -1.f, 1.f, -1.f, 0.5f);
  title  ();

  color  ("red");
  curve  (xray, y1ray, n);
  color  ("green");
  curve  (xray, y2ray, n);

  color  ("fore");
  dash   ();
  xaxgit ();
  disfin ();
}

/* >>>>>>>>>> EXA_2  <<<<<<<<<< */
void exa_2 (void)
{ int n = 300, m = 10, i;
  double f = 3.1415926 / 180., step, a;
  float x2[10], y2[10];
  
  step = 360. / (n - 1);

  for (i = 0; i < n; i++)
  { a = i * step * f;
    yray[i] = (float) a;
    xray[i] = (float) sin (5 * a);
  }

  for (i = 0; i < m; i++)
  { x2[i] = i + 1;
    y2[i] = i + 1;
  }

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();
  axspos (450,1800);

  titlin ("Polar Plots", 2);
  ticks  (3, "Y");
  axends ("NOENDS", "X");
  labdig (-1, "Y");
  axslen (1000, 1000);
  axsorg (1050, 900);

  grafp  (1.f ,0.f, 0.2f, 0.f, 30.f);
  curve  (xray, yray, n);
  htitle (50);
  title  ();
  endgrf ();

  labdig (-1, "X");
  axsorg (1050, 2250);
  labtyp ("VERT", "Y");
  grafp  (10.f, 0.f, 2.f, 0.f, 30.f);
  barwth (-5.f);
  polcrv ("FBARS");
  curve  (x2, y2, m);
  disfin ();
}

/* >>>>>>>>>> EXA_3  <<<<<<<<<< */
void exa_3 (void)
{ int nl, ny, i, nxp = 0;
  static char ctit[] = "Symbols", cstr[3];

  setpag ("da4p");
  disini ();
  pagera ();
  color  ("yellow");
  hwfont ();

  height (60);

  nl = nlmess (ctit);
  messag (ctit, (2100 - nl) / 2, 200);

  height (50);
  hsymbl (120);

  ny = 150;

  for (i = 0; i < 24; i++)
  { if ((i % 4) == 0) 
    { ny  += 400;
      nxp  = 550;
    }
    else
    { nxp += 350;
    }

    sprintf (cstr, "%d", i); 
    nl = nlmess (cstr) / 2;
    messag (cstr, nxp - nl, ny + 150);
    symbol (i, nxp, ny);
  }
  disfin ();
}

/* >>>>>>>>>> EXA_4  <<<<<<<<<< */
void exa_4 (void)
{ int nya, i;
  static char    ctit[]  = "Logarithmic Scaling", cstr[60],
                *clab[3] = {"LOG", "FLOAT", "ELOG"};

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();

  axslen (1400, 500);
  name   ("X-axis", "x");
  name   ("Y-axis", "y");
  axsscl ("log", "xy");

  titlin (ctit, 2);

  for (i = 1; i <= 3; i++)
  { nya = 2650 - (i - 1) * 800;
    labdig (-1, "xy");
    if (i == 2)
    { labdig (1, "y");
      name   (" ", "x");
    }

    axspos (500, nya);
    color  ("yellow");
    strcpy (cstr, "Labels: ");
    strcat (cstr, clab[i-1]);
    messag (cstr,600,nya-400);
    color  ("fore");
    labels (clab[i-1],"xy");
    graf   (0.f, 3.f, 0.f, 1.f, -1.f, 2.f, -1.f, 1.f);

    if (i == 3)
    { height (50);
      title  ();
    }

    endgrf ();
  }
  disfin ();
}

/* >>>>>>>>>> EXA_5  <<<<<<<<<< */
void exa_5 (void)
{ int nya = 2700, i, nx, ny;
  static float
        x[] = { 0.0f,  1.0f,  3.0f,  4.5f,  6.0f,  8.0f,  9.0f, 11.0f, 12.0f,
               12.5f, 13.0f, 15.0f, 16.0f, 17.0f, 19.0f, 20.0f},
        y[] = { 2.0f,  4.0f,  4.5f,  3.0f,  1.0f,  7.0f,  2.0f,  3.0f,  5.0f,
                2.0f,  2.5f,  2.0f,  4.0f,  6.0f,  5.5f,  4.0f};
  static char 
       *cpol[6] = {"SPLINE", "STEM", "BARS", "STAIRS", "STEP", "LINEAR"},
       *ctit    = "Interpolation Methods";

  setpag ("da4p");
  disini ();
  hwfont ();
  pagera ();
  incmrk (1);
  hsymbl (25);
  titlin (ctit, 1);
  axslen (1500, 350);
  setgrf ("line", "line", "line", "line");

  for (i = 0; i < 6; i++)
  { axspos (350, nya - i * 350);
    polcrv (cpol[i]);
    marker (0);

    graf   (0.f, 20.f, 0.f, 5.f, 0.f, 10.f, 0.f, 5.f);
    nx = nxposn (1.f);
    ny = nyposn (8.f);
    color  ("yellow");
    messag (cpol[i], nx, ny);
    curve (x, y, 16);
    color ("fore");

    if (i == 5)
    { height (50);
      title  ();
    }
    endgrf ();
  }

  disfin ();
}

/* >>>>>>>>>> EXA_6  <<<<<<<<<< */
void exa_6 (void)
{ int i, ny, nx;
  static float    x[2] = {3.f, 9.f}, y[2];
  static char *ctyp[8] = {"SOLID",  "DOT",   "DASH", "CHNDSH",
                          "CHNDOT", "DASHM", "DOTL", "DASHL"};

  setpag ("da4p");
  disini ();
  setvlt ("small");
  pagera ();
  center ();
  chncrv ("both");
  hwfont ();

  name   ("X-axis", "x");
  name   ("Y-axis", "y");

  titlin ("Demonstration of Curve", 1);
  titlin ("Line Styles", 3);

  graf   (0.f, 10.f, 0.f, 2.f, 0.f, 10.f, 0.f, 2.f);
  title  ();

  for (i = 1; i <= 8; i++)
  { y[0] = 9.5f - i;
    y[1] = 9.5f - i;
    ny = nyposn (y[0]);
    nx = nxposn (1.0f);
    messag (ctyp[i-1], nx, ny - 20);
    curve  (x, y, 2);
  }

  disfin ();
}

/* >>>>>>>>>> EXA_7  <<<<<<<<<< */
void exa_7 (void)
{ int n = 100, i, nx, ny;
  double fpi = 3.1415926/180., step, x;
  char   cbuf[20];

  step = 360. / (n - 1);
  for (i = 0; i < n; i++)
  { xray[i] = (float) (i * step);
    x=xray[i] * fpi;
    y1ray[i] = (float) sin (x);
    y2ray[i] = (float) cos (x);
  }

  disini ();
  hwfont ();
  pagera ();

  axspos (450, 1800);
  axslen (2200, 1200);

  name   ("X-axis", "x");
  name   ("Y-axis", "y");
  labdig (-1, "x");
  ticks  (10, "xy");

  titlin ("Demonstration of Curve", 1);
  titlin ("Legend", 3);

  graf   (0.f, 360.f, 0.f, 90.f, -1.f, 1.f, -1.f, 0.5f);
  title  ();
  xaxgit ();

  chncrv ("both");
  curve  (xray, y1ray, n);
  curve  (xray, y2ray, n);

  legini (cbuf, 2, 7);
  nx = nxposn (190.f);
  ny = nyposn (0.75f);
  legpos (nx, ny);
  leglin (cbuf, "sin (x)", 1);
  leglin (cbuf, "cos (x)", 2);
  legtit ("Legend");
  legend (cbuf, 3);
  disfin ();
}

/* >>>>>>>>>> EXA_8  <<<<<<<<<< */
void exa_8 (void)
{ int   ixp[4], iyp[4], nl, nx, nx0 = 335, ny0 = 350, ny, i, j, ii, k, iclr;
  static int  ix[4] = {0, 300, 300, 0},
              iy[4] = {0, 0, 400, 400};
  static char *ctit = "Shading Patterns (AREAF)", cstr[3];

  disini ();
  setvlt ("small");
  pagera ();
  hwfont ();

  height (50);
  nl = nlmess (ctit);
  nx = (2970 - nl) / 2;
  messag (ctit, nx, 200);

  iclr = 0;
  for (i = 0; i < 3; i++)
  { ny = ny0 + i * 600;
    for (j = 0; j < 6; j++)
    { nx = nx0 + j * 400;
      ii = i * 6 + j;
      shdpat ((long) ii);
      sprintf (cstr, "%d", ii);

      iclr = iclr % 8;
      iclr++;
      setclr (iclr);

      for (k = 0; k < 4; k++)
      { ixp[k] = ix[k] + nx;
        iyp[k] = iy[k] + ny;
      }
      areaf  (ixp, iyp, 4);

      nl  = nlmess (cstr);
      nx += (300 - nl) / 2;
      messag (cstr, nx, ny + 460);
    }
  }
  disfin ();
}

/* >>>>>>>>>> EXA_9  <<<<<<<<<< */
void exa_9 (void)
{ int nl, nx, ny, i;
  static int ivec[20]   = {   0,1111,1311,1421,1531,1701,1911,3111,3311,3421,
                           3531,3703,4221,4302,4413,4522,4701,5312,5502,5703};
  static char *ctit = "Vectors", cnum[5];

  disini ();
  color  ("cyan");
  pagera ();
  hwfont ();

  height (60);
  nl = nlmess (ctit);
  nx = (2970 - nl) / 2;
  messag (ctit, nx, 200);

  height (50);
  nx = 300;
  ny = 400;

  for (i = 0; i < 20; i++)
  { if (i == 10) 
    { nx += 2970 / 2;
      ny  = 400;
    }

    sprintf (cnum, "%d", ivec[i]);
    nl = nlmess (cnum);
    messag (cnum, nx - nl, ny - 25);

    vector (nx + 100, ny, nx + 1000, ny, ivec[i]);
    ny += 160;
  }
  disfin ();
}

/* >>>>>>>>>> EXA_10  <<<<<<<<<< */
void exa_10 (void)
{ int i;
  char cbuf[40], cstr[4];

  for (i = 0; i < 18; i++)
    xray[i] = 1.f;

  setpag ("da4p");
  disini ();
  setvlt ("small");
  pagera ();
  hwfont ();

  axspos (250, 2700);
  axslen (1600, 2200);
  titlin ("Shading Patterns (PIEGRF)", 3);
  height (50);

  legini (cbuf, 18, 2);

  for (i = 0; i < 18; i++)
  { sprintf (cstr, "%d", i);
    leglin (cbuf, cstr, i + 1);
  }

  chnpie ("both");
  labels ("none", "pie");
  piegrf (cbuf, 1, xray, 18);
  title  ();
  disfin ();
}

/* >>>>>>>>>> EXA_11 <<<<<<<<<< */
void exa_11 (void)
{ int n = 50 ,i, j;
  double fpi=3.1415927 / 180., step, x, y;

  step = 360. / (n - 1);
  for (i = 0; i < n; i++)
  { x = i * step;
    for (j = 0; j < n; j++)
    { y = j * step;
      zmat[i][j] = (float) (2 * sin (x * fpi) * sin (y * fpi));
    }
  }

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();
  axspos (200, 2600);
  axslen (1800, 1800);

  name   ("X-axis", "x");
  name   ("Y-axis", "y");
  name   ("Z-axis", "z");

  titlin ("Surface Plot (SURMAT)", 2);
  titlin ("F(X,Y) = 2*SIN(X)*SIN(Y)", 4);

  view3d (-5.f, -5.f, 4.f, "abs");
  graf3d (0.f, 360.f, 0.f, 90.f, 0.f, 360.f, 0.f, 90.f,
          -3.f, 3.f, -3.f, 1.f);
  height (50);
  title  ();

  color  ("green");
  surmat ((float *) zmat, 50, 50, 1, 1);
  disfin ();
}

/* >>>>>>>>>> EXA12_1 <<<<<<<<<< */
void exa12_1 (void)
{ int n = 50 ,i, j;
  static int ixp[4] = {200, 1999, 1999, 200},
             iyp[4] = {2600, 2600, 801, 801};

  double fpi = 3.1415927 / 180., step, x, y;

  step = 360. / (n - 1);
  for (i = 0; i < n; i++)
  { x = i * step;
    for (j = 0; j < n; j++)
    { y = j * step;
      zmat[i][j] = (float) (2 * sin (x * fpi) * sin (y * fpi));
    }
  }

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();

  axspos (200, 2600);
  axslen (1800, 1800);

  name   ("X-axis", "x");
  name   ("Y-axis", "y");
  name   ("Z-axis", "z");

  titlin ("Surface Plot (SURMAT)", 2);
  titlin ("F(X,Y) = 2*SIN(X)*SIN(Y)", 4);

  graf3d (0.f, 360.f, 0.f, 90.f, 0.f, 360.f, 0.f, 90.f,
          -3.f, 3.f, -3.f, 1.f);
  height (50);
  title  ();
  shlsur ();
  color  ("green");
  surmat ((float *) zmat, n, n, 1, 1);

  color  ("fore");
  grfini (-1.f, -1.f, -1.f, 1.f, -1.f, -1.f, 1.f, 1.f, -1.f);
  nograf ();
  graf   (0.f, 360.f, 0.f, 90.f, 0.f, 360.f, 0.f, 90.f);
  dashl  ();
  grid   (1,1);
  grffin ();

  grfini (-1.f, -1.f, -1.f, -1.f, 1.f, -1.f, -1.f, 1.f, 1.f);
  graf   (0.f, 360.f, 0.f, 90.f, -3.f, 3.f, -3.f, 1.f);
  grid   (1, 1);
  grffin ();

  grfini (-1.f, 1.f, -1.f, 1.f, 1.f, -1.f, 1.f, 1.f, 1.f);
  shdpat (7L);
  solid  ();
  areaf  (ixp, iyp, 4);
  grffin ();
  disfin ();
}

/* >>>>>>>>>> EXA12_2 <<<<<<<<<< */
void exa12_2 (void)
{ float p = 3.14159f, step;
  
   setpag ("da4p");
   disini ();
   pagera ();
   hwfont ();
   axspos (200, 2400);
   axslen (1800, 1800);
   intax  ();

   titlin ("Surface Plot of the Parametric Function", 2);
   titlin ("[COS(t)+(3+COS(u)), SIN(t)*(3+COS(u)), SIN(u)]", 4);

   name   ("X-axis", "x");
   name   ("Y-axis", "y");
   name   ("Z-axis", "z");

   vkytit (-300);
   zscale (-1.f, 1.f);
   graf3d (-4.f, 4.f, -4.f, 1.f, -4.f, 4.f, -4.f, 1.f,
	   -3.f, 3.f, -3.f, 1.f);
   height (40);
   title  ();

   surmsh ("on");
   step = (float) (2 * 3.14159 / 30.);
   surfcp (zfun, 0.f, 2 * p, step, 0.f, 2 * p, step);
   disfin ();
}

float zfun (float x, float y, int iopt)
{ double v;
  if (iopt == 1)
    v = cos ((double) x) * (3. + cos ((double) y));
  else if (iopt == 2)
    v = sin ((double) x) * (3. + cos ((double) y));
  else
    v = sin ((double) y);

  return (float) v;
}

/* >>>>>>>>>> EXA_12 <<<<<<<<<< */
void exa_12 (void)
{ int i, nxp, nyp;
  float  xp, yp;
  static float   xc[9] = {-22.f,18.f,37.5f,0.f,2.5f,12.5f,23.5f,-3.75f,14.25f},
                 yc[9] = {64.f,59.6f,56.f,51.5f,48.5f,42.f,38.f,40.3f,50.1f};
  static char *cstr[9] = {"REYKJAVIK", "STOCKHOLM", "MOSKAU", "LONDON",
                          "PARIS", "ROM", "ATHEN", "MADRID", "PRAG"};

  disini ();
  pagera ();
  hwfont ();

  axspos (500, 1850);
  axslen (2200, 1400);

  labdig (-1, "xy");
  ticks  (1, "xy");
  name   ("Longitude", "x");
  name   ("Latitude", "y");

  titlin ("Map Plot", 3);
  incmrk (-1);

  labels ("map", "xy");
  projct ("lambert");
  frame  (3);
  grafmp (-40.f, 60.f, -40.f, 20.f, 35.f, 70.f, 40.f, 10.f);

  color  ("green");
  world  ();
  color  ("fore");
  curvmp (xc, yc, 9);

  for (i = 0; i < 9; i++)
  { pos2pt (xc[i], yc[i], &xp, &yp);
    nxp = (int) (xp + 30);
    nyp = (int) yp;
    messag (cstr[i], nxp, nyp);
  }

  gridmp (1, 1);
  height (50);
  title  ();
  disfin ();
}

/* >>>>>>>>>> EX13_1 <<<<<<<<<< */
void ex13_1 (void)
{ setpag ("da4l");
  disini ();
  pagera ();
  hwfont ();

  frame  (3);
  axspos (400, 1850);
  axslen (2400, 1400);

  name   ("Longitude", "x");
  name   ("Latitude", "y");
  titlin ("World Coastlines and Lakes", 3);

  labels ("map", "xy");
  grafmp (-180.f, 180.f, -180.f, 90.f, -90.f, 90.f, -90.f, 30.f);

  gridmp (1, 1);
  color  ("green");
  world  ();
  color  ("fore");

  height (50);
  title  ();
  disfin ();
}

/* >>>>>>>>>> EX13_2 <<<<<<<<<< */
void ex13_2 (void)
{ int nya, i;
  static char *cproj[3] = {"Sanson", "Winkel", "Hammer"};
  char   ctit[61];

  setpag ("da4p");
  disini ();
  hwfont ();
  pagera ();

  height (40);
  axslen (1600, 750);

  nya = 3850;
  for (i = 0; i < 3; i++)
  { nya = nya - 950;
    axspos (250, nya);

    projct (cproj[i]);
    noclip ();
    grafmp (-180.f, 180.f, -180.f, 30.f, -90.f, 90.f, -90.f, 15.f);

    sprintf (ctit, "%s%s", "Elliptical Projection of ", cproj[i]);
    titlin (ctit, 4);
    title  ();
    color  ("green");
    world  ();
    color  ("fore");

    gridmp (1, 1);
    endgrf ();
  }
  disfin ();
}

/* >>>>>>>>>> EX13_3 <<<<<<<<<< */
void ex13_3 (void)
{ int    nl, nx, i;
  static int   nxa[4]  = {200, 1150, 200, 1150},
               nya[4]  = {1600, 1600, 2700, 2700};
  static float xpol[4] = {0.f, 0.f, 0.f, 0.f},
               ypol[4] = {0.f, 45.f, 90.f, -45.f};
  static char  *ctit   = "Azimuthal Lambert Projections";

  setpag ("da4p");
  disini ();
  hwfont ();
  pagera ();

  height (50);
  nl = nlmess (ctit);
  nx = (2250 - nl) / 2;
  messag (ctit, nx, 300);

  axslen (900, 900);
  projct ("lambert");

  for(i = 0; i < 4; i++)
  { axspos (nxa[i], nya[i]);
    mappol (xpol[i], ypol[i]);
    grafmp (-180.f, 180.f, -180.f, 30.f, -90.f, 90.f, -90.f, 30.f);

    color  ("green");
    world  ();
    color  ("fore");
    gridmp (1, 1);
    endgrf ();
  }
  disfin ();
}

/* >>>>>>>>>> EX13_4 <<<<<<<<<< */
void ex13_4 (void)
{ int n = 32, inray[32], icray[32], i;
  long ipray[32];

  for (i = 0; i < 32; i++)
  { inray[i] = i + 1;
    ipray[i] = 0;
    icray[i] = 1;
  }

  setpag ("da4p");
  disini ();
  setvlt ("small");
  pagera ();
  hwfont ();

  intax  ();
  ticks  (1, "xy");
  frame  (3);
  axslen (1600, 2200);
  axspos (400, 2700);

  name   ("Longitude", "x");
  name   ("Latitude", "y");
  titlin ("Conformal Conic Projection", 3);

  labels ("map", "xy");
  projct ("conf");
  grafmp (-10.f, 30.f, -10.f, 5.f, 35.f, 70.f, 35.f, 5.f);

  gridmp (1, 1);
  shdeur (inray, ipray, icray, n);

  height (50);
  title  ();
  disfin ();
}

/* >>>>>>>>>> EX14_1 <<<<<<<<<< */
void ex14_1 (void)
{ int n = 50, i, j;
  double   fpi = 3.14159 / 180., step, x, y;
  float  zlev;

  step = 360. / (n - 1);

  for (i = 0; i < n; i++)
  { xray[i] = (float) (i * step);
    yray[i] = (float) (i * step);
  }

  for (i = 0; i < n; i++)
  { for (j = 0; j < n; j++)
    { x = xray[i] * fpi;
      y = yray[j] * fpi;    
      zmat[i][j] = (float) (2 * sin (x) * sin (y));
    }
  }

  setpag ("da4p");
  disini ();
  complx ();
  pagera ();

  titlin ("Contour Plot", 1);
  titlin ("F(X,Y) = 2 * SIN(X) * SIN(Y)", 3);

  name   ("X-axis", "x");
  name   ("Y-axis", "y");

  intax  ();
  axspos (450, 2670);
  graf   (0.f, 360.f, 0.f, 90.f, 0.f, 360.f, 0.f, 90.f);

  height (30);
  for (i = 0; i < 9; i++)
  { zlev = (float) (-2. + i * 0.5);
    setclr ((i + 1) * 25);
    if (i == 4)
      labels ("none", "contur"); 
    else
      labels ("float", "contur");

    contur  (xray, n, yray, n, (float *) zmat, zlev);
  }

  height (50);
  color  ("fore");
  title  ();
  disfin ();
}

/* >>>>>>>>>> EX14_2 <<<<<<<<<< */
void ex14_2 (void)
{ int    n = 50, i, j;
  float zlev[12];
  double step, x, y;

  step = 1.6 / (n - 1);
  for (i = 0; i < n; i++)
  { x = 0.0 + i * step;
    xray[i] = (float) x;
    for (j = 0; j < n; j++)
    { y = 0.0 + j * step;
      yray[j] = (float) y;
      zmat[i][j] = (float) ((x * x - 1.) * (x * x - 1.) + 
                            (y * y - 1.) * (y * y - 1.));
    }
  }

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();

  mixalf ();
  titlin ("Shaded Contour Plot", 1);
  titlin ("F(X,Y) = (X[2$ - 1)[2$ + (Y[2$ - 1)[2$", 3);
  name   ("X-axis", "x");
  name   ("Y-axis", "y");

  shdmod ("poly", "contur");
  axspos (450, 2670);
  graf   (0.0f, 1.6f, 0.0f, 0.2f, 0.0f, 1.6f, 0.0f, 0.2f);

  for (i = 1; i <= 12; i++)
    zlev[12-i] = (float) (0.1 + (i - 1) * 0.1);

  conshd (xray, n, yray, n, (float *) zmat, zlev, 12);

  height (50);
  title  ();
  disfin ();
}

/* >>>>>>>>>> EX6_1  <<<<<<<<<< */
void ex6_1 (void)
{ int ny = 1100, nl;
  static char *ctit = "Instruction Alphabet",
  *ct1 = 
   "{m2}C{m4}(x) = {m3p}v{m4}e{e}-t{r}t{e}x-1{r}dt{gdh0.4f-1}0{u1.4m3f3}l",
  *ct2 =
   "lim{gdhc}x{m3cd1.1}a{c}l{rm} (1 + {puh} 1 {rvgd0.5h} x {r}){u1.2h}x{r} = e",
  *ct0 = 
   "Character{h0.5} height{rz-30}  incli{z30}nation {zw0.5} ratio {wk} fixed width",
  *ct3 = "Underscoring{l}    {p}twice{j}    vectors {pa8v}";

  setpag ("da4l");
  disini ();
  pagera ();
  hwfont ();
  color  ("cyan");

  height (50);
  nl = nlmess (ctit);
  messag (ctit, (2970 - nl) / 2, 250);

  height (36);
  messag ("1.)", 300, 450);
  messag (ct0, 500, 450);

  height (50);
  smxalf ("inst", "{", "}", 1);
  messag (ct0, 500, 550);

  reset  ("smxa");
  height (36);
  messag ("2.)", 300, 750);
  messag (ct3, 500, 750);

  height (50);
  smxalf ("inst", "{", "}", 1);
  messag (ct3, 500, 850);

  reset  ("smxalf");
  height (36);
  messag ("3.)", 300, ny);
  messag (ct1, 500, ny);

  smxalf ("inst", "{", "}", 1);
  height (80);
  messag (ct1, 900, ny + 150);

  height (36);
  reset  ("smxa");
  messag ("4.)", 300, ny + 450);
  messag (ct2, 500, ny + 450);

  height (80);
  smxalf ("inst", "{", "}", 1);
  messag (ct2, 900, ny + 600);
  disfin ();
}

/* >>>>>>>>>> EX10_1 <<<<<<<<<< */
void ex10_1 (void)
{ int nya = 2700, i;
  static char   *ctit = "Bar Graphs (BARS)", cbuf[25];

  static float x[9]  = {1.f, 2.f, 3.f, 4.f, 5.f, 6.f, 7.f, 8.f, 9.f},
               y[9]  = {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f},
               y1[9] = {1.f, 1.5f, 2.5f, 1.3f, 2.0f, 1.2f, 0.7f, 1.4f, 1.1f},
               y2[9] = {2.f, 2.7f, 3.5f, 2.1f, 3.2f, 1.9f, 2.0f, 2.3f, 1.8f},
               y3[9] = {4.f, 3.5f, 4.5f, 3.7f, 4.0f, 2.9f, 3.0f, 3.2f, 2.6f};

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();
  ticks  (1, "x");
  intax  ();;
  axslen (1600, 700);
  titlin (ctit, 3);

  legini (cbuf, 3, 8);
  leglin (cbuf, "FIRST", 1);
  leglin (cbuf, "SECOND", 2);
  leglin (cbuf, "THIRD", 3);
  legtit (" ");
  shdpat (5L);
  for (i = 1; i <= 3; i++)
  { if (i >  1) labels ("none", "x");
    axspos (300, nya - (i - 1) * 800);
    graf   (0.f, 10.f, 0.f, 1.f, 0.f, 5.f, 0.f, 1.f);

    if (i == 1)
    { bargrp (3, 0.15f);
      color  ("red");
      bars   (x, y, y1, 9);
      color  ("green");
      bars   (x, y, y2, 9);
      color  ("blue");
      bars   (x, y, y3, 9);
      color  ("fore");
      reset  ("bargrp");
    }
    else if (i == 2)
    { height (30);
      labels ("delta", "bars");
      labpos ("center", "bars");
      color  ("red");
      bars   (x, y, y1, 9);
      color  ("green");
      bars   (x, y1, y2, 9);
      color  ("blue");
      bars   (x, y2, y3, 9);
      color  ("fore");
      reset  ("height"); 
    }
    else if (i == 3)
    { labels ("second", "bars");
      labpos ("outside", "bars");
      color  ("red");
      bars   (x, y, y1, 9);
      color  ("fore");
    }

    if (i != 3) legend (cbuf, 7);

    if (i == 3)
    { height (50);
      title  ();
    }

    endgrf ();
  }
  disfin ();
}

/* >>>>>>>>>> EX10_2 <<<<<<<<<< */
void ex10_2 (void)
{ int nya = 2800, i;
  static char    *ctit = "Pie Charts (PIEGRF)", cbuf[41];
  static float xdray[5] = {1.f, 2.5f, 2.f, 2.7f, 1.8f};

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();
  axslen (1600, 1000);
  titlin (ctit, 2);
  chnpie ("both");

  legini (cbuf, 5, 8);
  leglin (cbuf, "FIRST", 1);
  leglin (cbuf, "SECOND", 2);
  leglin (cbuf, "THIRD", 3);
  leglin (cbuf, "FOURTH", 4);
  leglin (cbuf, "FIFTH", 5);

  patcyc (1, 7L);
  patcyc (2, 4L);
  patcyc (3, 13L);
  patcyc (4, 3L);
  patcyc (5, 5L);

  for (i = 0; i < 2; i++)
  { axspos (250,nya - i * 1200);
    if (i == 1)
    { labels ("data", "pie");
      labpos ("external", "pie");
    }
    piegrf (cbuf, 1, xdray, 5);

    if (i == 1)
    { height (50);
      title  ();
    }
    endgrf ();
  }
  disfin ();
}

/* >>>>>>>>>> EX10_3 <<<<<<<<<< */
void ex10_3 (void)
{ char cbuf[80];
  float x[5]  = {2., 4., 6., 8., 10.},
        y1[5] = {0., 0., 0., 0., 0.},
        y2[5] = {3.2, 1.5, 2.0, 1.0, 3.0};

  int ic1ray[5]  = {50, 150, 100, 200, 175},
      ic2ray[5]  = {50, 150, 100, 200, 175};

  setpag ("da4p");
  disini ();
  pagera ();
  hwfont ();

  titlin ("3-D Bar Graph / 3-D Pie Chart", 2);
  htitle (40);

  shdpat (16L);
  axslen (1500, 1000);
  axspos (300, 1400);

  barwth (0.5);
  bartyp ("3dvert");
  labels ("second", "bars");
  labpos ("outside", "bars");
  graf   (0., 12., 0., 2., 0., 5., 0., 1.);
  title  ();
  color  ("red");
  bars   (x, y1, y2, 5);
  endgrf ();

  shdpat (16L);
  labels ("data", "pie");
  chnpie ("none");
  pieclr (ic1ray, ic2ray, 5);
  pietyp ("3d");
  axspos (300, 2700);
  piegrf (cbuf, 0, y2, 5);       
  disfin ();
}

/* >>>>>>>>>> EX11_1 <<<<<<<<<< */
void ex11_1 (void)
{ int n = 50, i, j;
  double   fpi = 3.1415927 / 180., step, x, y;
  char   *cdev;

  step = 360. / (n - 1);
  for (i = 0; i < n; i++)
  { x = i * step;
    for (j = 0; j < n; j++)
    { y = j * step;
      zmat[i][j] = (float) (2 * sin (x * fpi) * sin (y * fpi));
    }
  }

  disini ();
  pagera ();
  cdev = getmfl ();
  hwfont ();

  titlin ("3-D Colour Plot of the Function", 2);
  titlin ("F(X,Y) = 2 * SIN(X) * SIN(Y)", 4);

  name   ("X-axis", "x");
  name   ("Y-axis", "y");
  name   ("Z-axis", "z");

  intax  ();
  autres (n, n);
  axspos (300, 1850);
  ax3len (2200, 1400, 1400);

  graf3  (0.f, 360.f, 0.f, 90.f, 0.f, 360.f, 0.f, 90.f,
          -2.f, 2.f, -2.f, 1.f);
  crvmat((float *) zmat, n, n, 1, 1);

  height (50);
  if (strcmp (cdev, "POST") == 0)
        psfont ("palatino-bolditalic");
  title  ();
  disfin ();
}

/* >>>>>>>>>> EXA_13 <<<<<<<<<< */
void exa_13()
{ int n = 7, i;
  static char
      *clr[7] = {"fore", "red", "yello", "cyan", "oran", "green", "blue"},
     *cont[7] = {"anta", "afri", "sout" , "aust", "nort", "eura", "lake"};

  disini ();
  hwfont ();
  setvlt ("small");
  pagera ();

  projct ("hammer");
  noclip ();
  grafmp (-180.f, 180.f, -180.f, 30.f, -90.f, 90.f, -90.f, 30.f);

  shdpat (16L);
  for (i = 0; i < n; i++)
  { color  (clr[i]); 
    shdmap (cont[i]);                               
    sendbf ();
  }

  color  ("fore");
  gridmp (1, 1);
  disfin ();
}

/* >>>>>>>>>> EXA_14 <<<<<<<<<< */
void exa_14 (void)
{ int ncol = 0, ny, i, j, nx, nb = 100, nh = 80, nl, ip, id_lis, ilis;
  float xcol;
  char   *cvlt;
  static char clis[] =
      {"SMALL|RAINBOW|SPECTRUM|TEMPERATURE|GREY|RRAIN|RGREY|VGA"};

  swgpop ("NOQUIT");
  swgpop ("NOHELP");

  ip = wgini ("vert");
  ilis = 2;
  wglab (ip, "Colour Table:");
  id_lis = wglis (ip, clis, ilis);
  wgok (ip);
  wgfin ();

  ilis = gwglis (id_lis);
  cvlt = itmstr (clis, ilis);

  disini ();
  setvlt (cvlt);
  pagera ();

  height (30);
  for (i = 1; i <= 13; i++)
  { ny = i * 150;
    nx = -50;
    for (j = 1; j <= 20; j++)
    { nx += 145;
      if (ncol <= 255)
      { point  (nx, ny, nb, nh, ncol);
        xcol = (float) ncol;
        nl = nlnumb (xcol, -1);
        color ("fore");  
        number (xcol, -1, nx - nl / 2, ny + 50);
        ncol++;
      }
    }
  }                   
  disfin ();
}