source: trunk/src/Utils/pgplot_related.c

/*
// -----------------------------------------------------------------------
// pgplot_related.c: New functions for use with PGPLOT.
// -----------------------------------------------------------------------
// Copyright (C) 2006, Matthew Whiting, ATNF
//
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2 of the License, or (at your
// option) any later version.
//
// Duchamp is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with Duchamp; if not, write to the Free Software Foundation,
// Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
//
// Correspondence concerning Duchamp may be directed to:
//    Internet email: Matthew.Whiting [at] atnf.csiro.au
//    Postal address: Dr. Matthew Whiting
//                    Australia Telescope National Facility, CSIRO
//                    PO Box 76
//                    Epping NSW 1710
//                    AUSTRALIA
// -----------------------------------------------------------------------
*/
#include <stdio.h>
#include <stdlib.h>
#include <cpgplot.h>
#include <math.h>
#include <string.h>
#include <ctype.h>

#define WDGPIX 100  /* used by cpgwedglog 
                       --> number of increments in the wedge. */

/*
 This file contains the following programs, all in C code:

  int cpgtest() --> a front-end to cpgqinf, to test whether a pgplot
                    device is currently open. 
  void cpgwedglog(const char* side, float disp, float width, 
                  float fg, float bg, const char *label)
                --> a C-code version of pgwedg, plotting the wedge 
                    scale in logarithmic units.
  void cpgcumul(int npts, float *data, float datamin, float datamax, 
                       int pgflag)
                --> a new pgplot routine that draws a cumulative 
                    distribution. Uses _swap and _sort.
  void cpghistlog(npts, data, datamin, datamax, nbin, pgflag)
                --> as for cpghist, with the y-axis on a logarithmic scale.

*/


/********************************************************************/
/*   CPGTEST                                                        */
/********************************************************************/

int cpgtest()
{
  /** 
   *     A front-end to cpgqinf, to test whether a pgplot device is 
   *     currently open. Returns 1 if there is, else 0.
   */
  char answer[10];                 /* The PGQINF return string */
  int answer_len = sizeof(answer); /* allocated size of answer[] */
  cpgqinf("STATE", answer, &answer_len);
  return strcmp(answer, "OPEN") == 0;
}

/********************************************************************/
/*   CPGWEDGLOG                                                     */
/********************************************************************/

void cpgwedglog(const char* side, float disp, float width, float fg, float bg, 
                const char *label)
{
  /** 
   *     A C-code version of PGWEDG that writes the scale of the wedge in 
   *      logarithmic coordinates. All parameters are exactly as for cpgwedg.
   */
  
  float wxa,wxb,wya,wyb, xa,xb,ya,yb; /* Temporary window coord storage.*/
  float vxa,vxb,vya,vyb;              /* Viewport coords of wedge. */
  float oldch, newch;                 /* Original and annotation character 
                                         heights. */
  float ndcsiz;                       /* Size of unit character height 
                                         (NDC units). */
  int horiz;                          /* Logical: True (=1) if wedge plotted 
                                         horizontally. */
  int image;                          /* Logical: Use PGIMAG (T=1) or 
                                         PGGRAY (F=0). */

  int nside,i;                        /* nside = symbolic version of side. */
  const int bot=1,top=2,lft=3,rgt=4;
  float wedwid, wdginc, vwidth, vdisp, xch, ych, labwid, fg1, bg1;
  float txtfrc=0.6;                   /* Set the fraction of WIDTH used 
                                             for anotation. */
  float txtsep=2.2;                   /* Char separation between numbers 
                                             and LABEL. */
  float wdgarr[WDGPIX];               /* Array to draw wedge in. */
  float tr[6] = {0.0,1.0,0.0,0.0,0.0,1.0};

/*   if(pgnoto("pgwedg")) return; */

  /* Get a numeric version of SIDE. */
  nside=bot; /* initialise */
  horiz=1;   /* initialise */
  if(tolower(side[0])=='b'){
    nside = bot;
    horiz = 1;
  }
  else if(tolower(side[0]=='t')){
    nside = top;
    horiz = 1;
  }
  else if(tolower(side[0]=='l')){
    nside = lft;
    horiz = 0;
  }
  else if(tolower(side[0]=='r')){
    nside = rgt;
    horiz = 0;
  }
  /*   else gwarn("Invalid \"SIDE\" argument in PGWEDG.");  */
  else fprintf(stdout,"%%PGPLOT, Invalid \"SIDE\" argument in CPGWEDGLOG.");

  /* Determine which routine to use. */
  image=0; /* initialise */
  if(strlen(side)<2) image = 0;
  else if(tolower(side[1])=='i') image = 1;
  else if(tolower(side[1])=='g') image = 0;
  else fprintf(stdout,"%%PGPLOT, Invalid \"SIDE\" argument in CPGWEDGLOG.");

  cpgbbuf();

  /* Store the current world and viewport coords and the character height. */
  cpgqwin(&wxa, &wxb, &wya, &wyb);
  cpgqvp(0, &xa, &xb, &ya, &yb);
  cpgqch(&oldch);

  /* Determine the unit character height in NDC coords. */
  cpgsch(1.0);
  cpgqcs(0, &xch, &ych);
  if(horiz == 1)  ndcsiz = ych;
  else ndcsiz = xch;

  /* Convert 'WIDTH' and 'DISP' into viewport units. */
  vwidth = width * ndcsiz * oldch;
  vdisp  = disp * ndcsiz * oldch;

  /* Determine the number of character heights required under the wedge. */
  labwid = txtsep;
  if(strcmp(label," ")!=0) labwid = labwid + 1.0;
  
  /* Determine and set the character height required to fit the wedge
     anotation text within the area allowed for it. */
  newch = txtfrc*vwidth / (labwid*ndcsiz);
  cpgsch(newch);

  /* Determine the width of the wedge part of the plot minus the anotation.
     (NDC units). */
  wedwid = vwidth * (1.0-txtfrc);

  /* Use these to determine viewport coordinates for the wedge + annotation.*/
  vxa = xa;
  vxb = xb;
  vya = ya;
  vyb = yb;
  if(nside==bot){
    vyb = ya - vdisp;
    vya = vyb - wedwid;
  }
  else if(nside==top) {
    vya = yb + vdisp;
    vyb = vya + wedwid;
  }
  else if(nside==lft) {
    vxb = xa - vdisp;
    vxa = vxb - wedwid;
  }
  else if(nside==rgt) {
    vxa = xb + vdisp;
    vxb = vxa + wedwid;
  }

  /* Set the viewport for the wedge. */
  cpgsvp(vxa, vxb, vya, vyb);

  /* Swap FG/BG if necessary to get axis direction right. */
/*   fg1 = max(fg,bg); */
/*   bg1 = min(fg,bg); */
  if(fg>bg) {
    fg1 = fg;
    bg1 = bg;
  }
  else {
    fg1 = bg;
    bg1 = fg;
  }


  /* Create a dummy wedge array to be plotted. */
  wdginc = (fg1-bg1)/(WDGPIX-1);
  for(i=0;i<WDGPIX;i++)  wdgarr[i] = bg1 + (i-1) * wdginc;

  /* Draw the wedge then change the world coordinates for labelling. */
  if (horiz==1) {
    cpgswin(1.0, (float)WDGPIX, 0.9, 1.1);
    if (image==1) cpgimag(wdgarr, WDGPIX,1, 1,WDGPIX, 1,1, fg,bg, tr);
    else          cpggray(wdgarr, WDGPIX,1, 1,WDGPIX, 1,1, fg,bg, tr);
    cpgswin(bg1,fg1,0.0,1.0);
  }
  else{
    cpgswin(0.9, 1.1, 1.0, (float)WDGPIX);
    if (image==1) cpgimag(wdgarr, 1,WDGPIX, 1,1, 1,WDGPIX, fg,bg, tr);
    else          cpggray(wdgarr, 1,WDGPIX, 1,1, 1,WDGPIX, fg,bg, tr);
    cpgswin(0.0, 1.0, bg1, fg1);
  }

  /* Draw a labelled frame around the wedge -- using a logarithmic scale! */
  if(nside==bot)  cpgbox("BCNSTL",0.0,0,"BC",0.0,0);
  else if(nside==top) cpgbox("BCMSTL",0.0,0,"BC",0.0,0);
  else if(nside==lft) cpgbox("BC",0.0,0,"BCNSTL",0.0,0);
  else if(nside==rgt) cpgbox("BC",0.0,0,"BCMSTL",0.0,0);

  /* Write the units label. */
  if((strcmp(label," ")!=0)) cpgmtxt(side,txtsep,1.0,1.0,label);

  /* Reset the original viewport and world coordinates. */
  cpgsvp(xa,xb,ya,yb);
  cpgswin(wxa,wxb,wya,wyb);
  cpgsch(oldch);
  cpgebuf();

}


/********************************************************************/
/*   CPGCUMUL                                                       */
/********************************************************************/

void _swap(float *a, float *b)
{ 
  float t;
  t=*a; *a=*b; *b=t; 
}

void _sort(float *array, int begin, int end) 
{
  float pivot = array[begin];
  int i = begin + 1, j = end, k = end;
  float t;

  while (i < j) {
    if (array[i] < pivot) i++;
    else if (array[i] > pivot) {
      j--; k--;
      t = array[i];
      array[i] = array[j];
      array[j] = array[k];
      array[k] = t; }
    else {
      j--;
      _swap(&array[i], &array[j]);
    }  }
  i--;
  _swap(&array[begin], &array[i]);        
  if (i - begin > 1)
    _sort(array, begin, i);
  if (end - k   > 1)
    _sort(array, k, end);                      
}


void cpgcumul(int npts, float *data, float datamin, float datamax, int pgflag)
{
  /** 
   *  A new pgplot routine that draws a cumulative distribution.
   *   The use of pgflag is similar to cpghist & cpghist_log:

   *   <ul><li> 0 --> draw a new graph using cpgenv, going from 0 to 1
   *                  on the y-axis.
   *       <li> 2 --> draw the plot on the current graph, without
   *                  re-drawing any axes.  
   *   </ul>
   */

  int i;
  float *sorted;
  float MINCOUNT=0.;

  sorted = (float *)calloc(npts,sizeof(float));
  for(i=0;i<npts;i++) sorted[i] = data[i];
  _sort(sorted,0,npts);

  cpgbbuf();

  /* DEFINE ENVIRONMENT IF NECESSARY */
  if(pgflag == 0) cpgenv(datamin,datamax,MINCOUNT,1.0001,0,0);
  if(pgflag == 2) cpgswin(datamin,datamax,MINCOUNT,1.);

  /* DRAW LINE */
  cpgmove(datamin,MINCOUNT);
  for(i=0;i<npts;i++) cpgdraw(sorted[i],(float)(i+1)/(float)(npts));
  cpgdraw(datamax,1.);

  cpgebuf();
  
  free(sorted);

}

/********************************************************************/
/*   CPGHISTLOG                                                     */
/********************************************************************/

void cpghistlog(int npts, float *data, float datamin, float datamax, int nbin, 
                int pgflag)
{
  /**
   *  Works exactly as for cpghist, except the y-axis is a logarithmic scale.
   *
   */


  int i,bin;
  float *num;
  float maxNum,binSize,x1,x2,y1,y2,older,newer,fraction;
  float MINCOUNT=-0.2;

  num = (float *)calloc(nbin,sizeof(float));

  cpgbbuf();

  /* HOW MANY VALUES IN EACH BIN? */
  for(i=0; i<npts; i++){
    fraction = (data[i] - datamin) / (datamax - datamin);
    bin = (int)( floor(fraction*nbin) );
    if((bin>=0)&&(bin<nbin)) num[bin]+=1.;
  }
  for(i=0; i<nbin;i++){
    if(num[i]>0) num[i] = log10(num[i]);
    else num[i] = MINCOUNT;
  }
  maxNum = num[0];
  for(i=1; i<nbin; i++) if(num[i]>maxNum) maxNum = num[i];
  binSize = (datamax - datamin) / (float)nbin;

  /* BOUNDARIES OF PLOT */
  x1 = datamin;
  x2 = datamax;
  y1 = MINCOUNT;
  y2 = ceil(maxNum);

  /* DEFINE ENVIRONMENT IF NECESSARY */
  if(pgflag%2 == 0) cpgenv(x1,x2,y1,y2,0,20);

  /* DRAW HISTOGRAM */
  if(pgflag/2 == 0){
    older = 0.;
    x2 = datamin;
    cpgmove(datamin,MINCOUNT);
    for(i=0;i<nbin;i++){
      newer = num[i];
      x1 = x2;
      x2 = datamin + i*binSize;
      if(newer!=MINCOUNT){
        if(newer<=older){
          cpgmove(x1,newer);
          cpgdraw(x2,newer);
        }
        else{
          cpgmove(x1,older);
          cpgdraw(x1,newer);
          cpgdraw(x2,newer);
        }
      }
      cpgdraw(x2,MINCOUNT);
      older=newer;
    }
  }
  else if(pgflag/2 == 1){
    older = MINCOUNT;
    x2 = datamin;
    for(i=0;i<nbin;i++){
      newer = num[i];
      x1 = x2;
      x2 = datamin + i*binSize;
      if(newer!=MINCOUNT) cpgrect(x1,x2,0.,newer);      
    }
  }
  else if(pgflag/2 == 2){
    older = 0.;
    cpgmove(datamin,MINCOUNT);
    x2 = datamin;
    for(i=0;i<nbin;i++){
      newer = num[i];
      x1 = x2;
      x2 = datamin + i*binSize;
      if((newer==MINCOUNT)&&(older==MINCOUNT)) cpgmove(x2,MINCOUNT);
      else {
        cpgdraw(x1,newer);
        if(newer==MINCOUNT) cpgmove(x2,newer);
        else cpgdraw(x2,newer);
      }
      older = newer;
    }
  }

  if(num){
      free(num);
  }
  
  cpgebuf();
    
}

/********************************************************************/
/*   CPGELLIPSE                                                     */
/********************************************************************/


void cpgellipse(float x0, float y0, float maj, float min, float pa)
{
  /*
    Draw an ellipse, using the parametric equation u = a cos(t), v = b sin(t), where u and v are coordinates such that the position angle of the ellipse is zero.
   */
  double cospa,sinpa,u,v,x,y,t;
  int it;
  cospa = cos(pa*M_PI/180.);
  sinpa = sin(pa*M_PI/180.);
  u=maj;
  v=0.;
  x=u*cospa+v*sinpa;
  y=u*sinpa-v*cospa;
  cpgmove(x+x0,y+y0);
  for(it=0;it<1000;it++){
    t=it*2*M_PI/1000.;
    u=maj*cos(t);
    v=min*sin(t);
    x=u*cospa+v*sinpa;
    y=u*sinpa-v*cospa;
    cpgdraw(x+x0,y+y0);
  }
}


/* /\********************************************************************\/ */
/* /\*   CPGVERTHIST                                                    *\/ */
/* /\********************************************************************\/ */

/* void cpgverthist(int npts, float *data, float datamin, float datamax, int nbin,  */
/*               int pgflag) */
/* { */
/*   /\** */
/*    *  Works exactly as for cpghist, except the histogram is draw vertically. */
/*    * */
/*    *\/ */


/*   int i,bin; */
/*   float *num; */
/*   float maxNum,binSize,x1,x2,y1,y2,older,newer,fraction; */
/*   float MINCOUNT=-0.2; */

/*   num = (float *)calloc(nbin,sizeof(float)); */

/*   cpgbbuf(); */

/*   /\* HOW MANY VALUES IN EACH BIN? *\/ */
/*   for(i=0; i<npts; i++){ */
/*     fraction = (data[i] - datamin) / (datamax - datamin); */
/*     bin = (int)( floor(fraction*nbin) ); */
/*     if((bin>=0)&&(bin<nbin)) num[bin]+=1.; */
/*   } */
/*   for(i=0; i<nbin;i++){ */
/*     if(num[i]>0) num[i] = log10(num[i]); */
/*     else num[i] = MINCOUNT; */
/*   } */
/*   maxNum = num[0]; */
/*   for(i=1; i<nbin; i++) if(num[i]>maxNum) maxNum = num[i]; */
/*   binSize = (datamax - datamin) / (float)nbin; */

/*   /\* BOUNDARIES OF PLOT *\/ */
/*   x1 = datamin; */
/*   x2 = datamax; */
/*   y1 = MINCOUNT; */
/*   y2 = ceil(maxNum); */

/*   /\* DEFINE ENVIRONMENT IF NECESSARY *\/ */
/*   if(pgflag%2 == 0) cpgenv(x1,x2,y1,y2,0,20); */

/*   /\* DRAW HISTOGRAM *\/ */
/*   if(pgflag/2 == 0){ */
/*     older = 0.; */
/*     x2 = datamin; */
/*     cpgmove(datamin,MINCOUNT); */
/*     for(i=0;i<nbin;i++){ */
/*       newer = num[i]; */
/*       x1 = x2; */
/*       x2 = datamin + i*binSize; */
/*       if(newer!=MINCOUNT){ */
/*      if(newer<=older){ */
/*        cpgmove(x1,newer); */
/*        cpgdraw(x2,newer); */
/*      } */
/*      else{ */
/*        cpgmove(x1,older); */
/*        cpgdraw(x1,newer); */
/*        cpgdraw(x2,newer); */
/*      } */
/*       } */
/*       cpgdraw(x2,MINCOUNT); */
/*       older=newer; */
/*     } */
/*   } */
/*   else if(pgflag/2 == 1){ */
/*     older = MINCOUNT; */
/*     x2 = datamin; */
/*     for(i=0;i<nbin;i++){ */
/*       newer = num[i]; */
/*       x1 = x2; */
/*       x2 = datamin + i*binSize; */
/*       if(newer!=MINCOUNT) cpgrect(x1,x2,0.,newer);    */
/*     } */
/*   } */
/*   else if(pgflag/2 == 2){ */
/*     older = 0.; */
/*     cpgmove(datamin,MINCOUNT); */
/*     x2 = datamin; */
/*     for(i=0;i<nbin;i++){ */
/*       newer = num[i]; */
/*       x1 = x2; */
/*       x2 = datamin + i*binSize; */
/*       if((newer==MINCOUNT)&&(older==MINCOUNT)) cpgmove(x2,MINCOUNT); */
/*       else { */
/*      cpgdraw(x1,newer); */
/*      if(newer==MINCOUNT) cpgmove(x2,newer); */
/*      else cpgdraw(x2,newer); */
/*       } */
/*       older = newer; */
/*     } */
/*   } */

/*   cpgebuf(); */
    
/* } */