File:Julia set for z^2+0.7i*z.png

From Department of Mathematics at UTSA
Jump to navigation Jump to search

Original file(2,000 × 2,000 pixels, file size: 610 KB, MIME type: image/png)

This file is from Wikimedia Commons and may be used by other projects. The description on its file description page there is shown below.

This image could be re-created using vector graphics as an SVG file. This has several advantages; see Commons:Media for cleanup for more information. If an SVG form of this image is available, please upload it and afterwards replace this template with {{vector version available|new image name}}.


It is recommended to name the SVG file “Julia set for z^2+0.7i*z.svg”—then the template Vector version available (or Vva) does not need the new image name parameter.

Summary

Description
English: Dynamic plane with Julia set for . Made with LCM = Level Curves Method. Level curves are boundaries of level sets ( escape and attraction time). Point escapes to infinityu or is attracted to the finite attractor ( here fixed point). The Julia set (boundary of filled-in Julia set) itself is not drawn: we see it as the locus of points where the level curves are especially close to each other = a place with high density of level curves. Points of critical orbit ( including crirital point and fixed point = finite attractor) are on the level curves like notes on the musical staff. Level curves cross at critical point and its preimages = saddle points. Compare it with fig 11 in 3-rd edition from 2006 of Dynamics in one complex variable: introductory lectures by John W. Milnor. ( or fig 5 from the preprint on Arxiv[1]. Critical point z= -0.35*i is the center of symmetry and lemniscate ( point in which level curves cross). Attracting fixed point z= 0 is the center of nested circles above the critical point. Preimage of fixed point z= -0.7*i is a the center of nested circles below the critical point.)
Date
Source Own work
Author Adam majewski

Licensing

I, the copyright holder of this work, hereby publish it under the following license:
w:en:Creative Commons
attribution share alike
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
  • share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.


c source code

/*

https://arxiv.org/abs/math/9201272
Dynamics in one complex variable: introductory lectures
John W. Milnor

Figure 5. Julia set for z 7→ z^2 + .7z , with curves |φ| = constant .
or fig 11 in 3-rd edition from 2006 







  Adam Majewski
  adammaj1 aaattt o2 dot pl  // o like oxygen not 0 like zero 
  
  
  
  Structure of a program or how to analyze the program 
  
  
  ============== Image X ========================
  
  DrawImageOf -> DrawPointOf -> ComputeColorOf ( FunctionTypeT FunctionType , complex double z) -> ComputeColor
  
  
  check only last function  which computes color of one pixel for given Function Type
  
  

   
  ==========================================

  
  ---------------------------------
  indent d.c 
  default is gnu style 
  -------------------



  c console progam 
  
  export  OMP_DISPLAY_ENV="TRUE"	
  gcc d.c -lm -Wall -march=native -fopenmp
  time ./a.out > b.txt


  gcc d.c -lm -Wall -march=native -fopenmp


  time ./a.out

  time ./a.out >i.txt
  time ./a.out >e.txt
  
  
  
  
  
  
  convert -limit memory 1000mb -limit disk 1gb dd30010000_20_3_0.90.pgm -resize 2000x2000 10.png

  
  
  
*/

#include <stdio.h>
#include <stdlib.h>		// malloc
#include <string.h>		// strcat
#include <math.h>		// M_PI; needs -lm also
#include <complex.h>
#include <omp.h>		// OpenMP
#include <limits.h>		// Maximum value for an unsigned long long int



// https://sourceforge.net/p/predef/wiki/Standards/

#if defined(__STDC__)
#define PREDEF_STANDARD_C_1989
#if defined(__STDC_VERSION__)
#if (__STDC_VERSION__ >= 199409L)
#define PREDEF_STANDARD_C_1994
#endif
#if (__STDC_VERSION__ >= 199901L)
#define PREDEF_STANDARD_C_1999
#endif
#endif
#endif




/* --------------------------------- global variables and consts ------------------------------------------------------------ */


//FunctionType
typedef enum  {Fatou = 0, IntLSM =1 , ExtLSM = 2, LSM = 3, DEM = 4, Unknown = 5 , BD = 6, MBD = 7 , SAC = 8, DLD = 9, ND = 10 , NP= 11, POT = 12 , Blend = 13
		
} FunctionTypeT; 
// FunctionTypeT FunctionType;

// virtual 2D array and integer ( screen) coordinate
// Indexes of array starts from 0 not 1 
//unsigned int ix, iy; // var
static unsigned int ixMin = 0;	// Indexes of array starts from 0 not 1
static unsigned int ixMax;	//
static unsigned int iWidth;	// horizontal dimension of array

static unsigned int iyMin = 0;	// Indexes of array starts from 0 not 1
static unsigned int iyMax;	//

static unsigned int iHeight = 20000;	//  
// The size of array has to be a positive constant integer 
static unsigned long long int iSize;	// = iWidth*iHeight; 

// memmory 1D array 
unsigned char *data;
unsigned char *edge;
//unsigned char *edge2;

// unsigned int i; // var = index of 1D array
//static unsigned int iMin = 0; // Indexes of array starts from 0 not 1
static unsigned int iMax;	// = i2Dsize-1  = 
// The size of array has to be a positive constant integer 
// unsigned int i1Dsize ; // = i2Dsize  = (iMax -iMin + 1) =  ;  1D array with the same size as 2D array



// see SetPlane

double radius = 1.3; 
complex double center ;
double  DisplayAspectRatio  = 1.0; // https://en.wikipedia.org/wiki/Aspect_ratio_(image)
// dx = dy compare setup : iWidth = iHeight;
double ZxMin; //= -1.3;	//-0.05;
double ZxMax;// = 1.3;	//0.75;
double ZyMin;// = -1.3;	//-0.1;
double ZyMax;// = 1.3;	//0.7;
double PixelWidth;	// =(ZxMax-ZxMin)/ixMax;
double PixelHeight;	// =(ZyMax-ZyMin)/iyMax;

double ratio; 


/*
  ER = pow(10,ERe);
  AR = pow(10,-ARe);
*/
//int ARe ;			// increase ARe until black ( unknown) points disapear 
//int ERe ;
double ER;
double ER2;			//= 1e60;
double AR; // bigger values do not works
double AR2;

double AR_max;
//double AR12;



int IterMax = 100000;
int IterMax_LSM = 1000;


/* colors = shades of gray from 0 to 255 

   unsigned char colorArray[2][2]={{255,231},    {123,99}};
   color = 245;  exterior 
*/
unsigned char iColorOfExterior = 245;
unsigned char iColorOfInterior1 = 99;
unsigned char iColorOfInterior2 = 183;
unsigned char iColorOfBoundary = 0;
unsigned char iColorOfUnknown = 5;

// pixel counters
unsigned long long int uUnknown = 0;
unsigned long long int uInterior = 0;
unsigned long long int uExterior = 0;



// critical points




// critical points
complex double zcr = -0.35*I; // only one critical point 
//complex double zc2 = -2.2351741790771484375e-08+9.4296410679817199707e-09*I;


/*

  

*/



/* 

coefficients read from input file milnor_fig11.txt
	degree 2 coefficient = ( +1.0000000000000000 +0.0000000000000000*i) 
	degree 1 coefficient = ( +0.0000000000000000 +0.7000000000000000*i) 

Input polynomial p(z)=(1+0i)*z^2+(0+0.69999999999999995559i)*z^1

derivative dp/dz = (2+0i)*z^1+(0+0.69999999999999995559i)

1 critical points found

	cp#0: 0,-0.3499999999999999778 . It's critical orbit is bounded and enters cycle #0 length=1 and it's stability = |multiplier|=0.7 =attractive 
	internal angle = 0.25
cycle = {
-4.9406564584124654418e-324,4.9406564584124654418e-324 ; }
*/
const complex double C =0.7*I;
const int period = 1;

// periodic points = attractors
complex double z1 =  0.0 ; //fixed point (period  1) =  attracting cycle



/* ------------------------------------------ functions -------------------------------------------------------------*/


// complex function
complex double fc(const complex double z0, const complex double c) {

	double complex z = z0;
	z = z*z + z*c;
	return  z;
	}
	

// iterated function
complex double Fpc(const complex double z0, const complex double c, const int period) {

	int p;
	int pMax = period;
	double complex z = z0;
	
	for (p=0; p< pMax; ++p ){
	
		z = fc(z,c);}
	return z;
	}
		








//------------------complex numbers -----------------------------------------------------





// from screen to world coordinate ; linear mapping
// uses global cons
double
GiveZx (int ix)
{
  return (ZxMin + ix * PixelWidth);
}

// uses globaal cons
double
GiveZy (int iy)
{
  return (ZyMax - iy * PixelHeight);
}				// reverse y axis


complex double
GiveZ (int ix, int iy)
{
  double Zx = GiveZx (ix);
  double Zy = GiveZy (iy);

  return Zx + Zy * I;




}



double cabs2(complex double z){

  return creal(z)*creal(z)+cimag(z)*cimag(z);


}




/* find such AR for internal LCM/J and LSM that level curves croses critical point and it's preimages
for attracting ( also weakly attracting = parabolic) dynamics

it may fail if one iteration is bigger then smallest distance between periodic point and Julia set
*/
double GiveTunedAR(const int iter_Max, const double complex c , const double AR_max){

  fprintf(stdout, " GiveTunedAR\n");

  complex double z = zcr; // initial point z0 = criical point 
  int iter;
  double r; 
  //int i_Max = 1000;
  
  for (iter=0; iter< iter_Max; ++iter ){
  // period !!!
  	r = cabs(z-z1);
  	//fprintf(stdout, " i = %d z = %f %+f \t r = %f = %d * pixeWidth \n",iter , creal(z), cimag(z),   r, (int) (r/PixelWidth));
  	
  	z = fc(z,c); // forward iteration
  	
  
  }
  
  
  r = cabs(z-z1);
  fprintf(stdout, "  r = %f = %d * pixeWidth \n",  r, (int) (r/PixelWidth));
  if ( r> cabs(z-z1)) 
  	{ 	//fprintf(stdout, "one more forward iteration \n");
  		z = fc(z,c); 
  		r = cabs(z-z1);
  	}
  
  
  if ( r > AR_max ) 
  	{
  		//fprintf(stdout, " AR_max < r = %f = %d * pixeWidth \n",  r, (int) (r/PixelWidth));
  		//fprintf(stdout, " increase i_max\n" );
  	  r = AR_max;}	// manual check
	 

	 
 return r;
	
	
}






// =====================
int IsPointInsideTrap(complex double  z){

	
	 
	
  if ( cabs2(z - z1) < AR2 ) {return 1;} // circle around z2a 
  
  
  return 0; // outside



}






int IsPointInsideTraps(complex double  z){

	
	 
	
  if ( IsPointInsideTrap(z)  ) {return 1;} // 
	
  
	
  return 0; // outside



}



// =====================
int IsPixelInsideTraps(unsigned int ix, unsigned int iy){

	
  complex double  z = GiveZ (ix, iy);
	
  if ( IsPointInsideTraps(z) ) {return 1;} // 
	
  
	
  return 0; // outside



}




// ****************** DYNAMICS = trap tests ( target sets) ****************************


/* -----------  array functions = drawing -------------- */

/* gives position of 2D point (ix,iy) in 1D array  ; uses also global variable iWidth */
unsigned int Give_i (unsigned int ix, unsigned int iy)
{
  return ix + iy * iWidth;
}



// 
unsigned char ComputeColorOfFatou (complex double z)
{



	
	
  double r2;


  int i;			// number of iteration
  for (i = 0; i < IterMax; ++i)
    {


		
	
        r2 =cabs2(z);
		
      if (r2 > ER2) // esaping = exterior
	{
	  uExterior += 1;
	  return iColorOfExterior;
	}			
	
      // solid color for each Fatou components
	
      if ( IsPointInsideTrap(z)) {
	uInterior +=1;
	if ( i % period ) 
		{return iColorOfInterior1;}
		else {return iColorOfInterior2;}
      } // 50 + (i % 114); }
	
	z = fc(z,C);		// complex iteration f(z)=z^3 + c

    }

  uUnknown += 1;
  return iColorOfUnknown;


}




// f(z)=1+z−3z2−3.75z3+1.5z4+2.25z5
unsigned char ComputeColorOfLSM (complex double z)
{



	
	
  double r2;


  int i;			// number of iteration
  for (i = 0; i < IterMax_LSM; ++i)
    {


		

     	// complex iteration f(z)=z^3 + c
            r2 =cabs2(z);
		
      if (r2 > ER2) // esaping = exterior
	{
	  uExterior += 1;
	  return 255- ((i*15) % 255);
	}			
	
      // solid color for each Fatou components
	
      if ( IsPointInsideTrap(z)) {
	uInterior +=1;
	if ( i % 2 ) 
		{return (i*9) % 255  ;}
		else {return (i*10) % 255;}
      } // 50 + (i % 114); }
	
	 z = fc(z,C);	

    }

  uUnknown += 1;
  return iColorOfUnknown;


}




/* ==================================================================================================
   ============================= Draw functions ===============================================================
   =====================================================================================================
*/ 
unsigned char ComputeColor(FunctionTypeT FunctionType, complex double z){

  unsigned char iColor;
	
	
	
  switch(FunctionType){
  
  	case Fatou :{iColor = ComputeColorOfFatou(z); break;}
  
 
 	// case IntLSM :{iColor = ComputeColorOfIntLSM(z); break;}
	
 	// case ExtLSM :{iColor = ComputeColorOfExtLSM(z); break;}
  
  	case LSM :{iColor = ComputeColorOfLSM(z); break;}
  
  	/*
		
  	case DEM : {iColor = ComputeColorOfDEM(z); break;}
		
  	case Unknown : {iColor = ComputeColorOfUnknown(z); break;}
		
  	case BD : {iColor = ComputeColorOfBD(z); break;}
		
  	case MBD : {iColor = ComputeColorOfMBD(z); break;}
		
  	case SAC : {iColor = ComputeColorOfSAC(z); break;}
  
  	case DLD : {iColor = ComputeColorOfDLD(z); break;}
		
  	case ND : {iColor = ComputeColorOfND(z); break;}
		
  	case NP : {iColor = ComputeColorOfNP(z); break;}
		
  	case POT : {iColor = ComputeColorOfPOT(z); break;}
		
  	case Blend : {iColor = ComputeColorOfBlend(z); break;}
  	*/		
	
  	default: {}
	
	
  	}
	
  return iColor;



}


// plots raster point (ix,iy) 
int DrawPoint ( unsigned char A[], FunctionTypeT FunctionType, int ix, int iy)
{
  int i;			/* index of 1D array */
  unsigned char iColor;
  complex double z;


  i = Give_i (ix, iy);		/* compute index of 1D array from indices of 2D array */
  
  z = GiveZ(ix,iy);
  

  iColor = ComputeColor(FunctionType, z);
  A[i] = iColor ;		// 
  
  return 0;
}




int DrawImage ( unsigned char A[], FunctionTypeT FunctionType)
{
  unsigned int ix, iy;		// pixel coordinate 

  fprintf (stdout, "compute Fatou image LSM\n");
  // for all pixels of image 
#pragma omp parallel for schedule(dynamic) private(ix,iy) shared(A, ixMax , iyMax, uUnknown, uInterior, uExterior)
  for (iy = iyMin; iy <= iyMax; ++iy)
    {
      fprintf (stderr, " %d from %d \r", iy, iyMax);	//info 
      for (ix = ixMin; ix <= ixMax; ++ix)
	DrawPoint(A, FunctionType, ix, iy);	//  
    }

  return 0;
}





int IsInside (int x, int y, int xcenter, int ycenter, int r){

	
  double dx = x- xcenter;
  double dy = y - ycenter;
  double d = sqrt(dx*dx+dy*dy);
  if (d<r) 
    return 1;
  return 0;
	  

} 

int PlotBigPoint(complex double z, unsigned char A[]){

	
  unsigned int ix_seed = (creal(z)-ZxMin)/PixelWidth;
  unsigned int iy_seed = (ZyMax - cimag(z))/PixelHeight;
  unsigned int i;
	
	
  /* mark seed point by big pixel */
  int iSide =4.0*iWidth/2000.0 ; /* half of width or height of big pixel */
  int iY;
  int iX;
  for(iY=iy_seed-iSide;iY<=iy_seed+iSide;++iY){ 
    for(iX=ix_seed-iSide;iX<=ix_seed+iSide;++iX){ 
      if (IsInside(iX, iY, ix_seed, iy_seed, iSide)) {
	i= Give_i(iX,iY); /* index of _data array */
	A[i]= 0; //255-A[i];
	}}}
	
	
  return 0;
	
}


// fill array 
// uses global var :  ...
// scanning complex plane 
int MarkAttractors (unsigned char A[])
{
  
	
	
	
  fprintf (stdout, "mark attractors \n");
  
  PlotBigPoint(z1, A); // period 1  cycle
  //PlotBigPoint(z2b, A);	// 
    		 
      	

  return 0;
}






int MarkTraps(unsigned char A[]){

  unsigned int ix, iy;		// pixel coordinate 
  unsigned int i;


  fprintf (stdout ,"Mark traps \n");
  // for all pixels of image 
#pragma omp parallel for schedule(dynamic) private(ix,iy) shared(A, ixMax , iyMax, uUnknown, uInterior, uExterior)
  for (iy = iyMin; iy <= iyMax; ++iy)
    {
      fprintf (stdout, " %d from %d \r", iy, iyMax);	//info 
      for (ix = ixMin; ix <= ixMax; ++ix){
	if (IsPixelInsideTraps(ix, iy)) {
	  i= Give_i(ix,iy); /* index of _data array */
	  A[i]= 255-A[i]; // inverse color
	}}}
  return 0;
}






int PlotPoint(complex double z, unsigned char A[]){

	
  unsigned int ix = (creal(z)-ZxMin)/PixelWidth;
  unsigned int iy = (ZyMax - cimag(z))/PixelHeight;
  unsigned int i = Give_i(ix,iy); /* index of _data array */
	
	
  A[i]= 0; //255-A[i]; // Mark point with inveres color
	
	
  return 0;
	
}


int DrawForwardOrbit(complex double z, unsigned long long int iMax,  unsigned char A[] )
{
  
  unsigned long long int i; /* nr of point of critical orbit */
  printf("draw forward orbit \n");
 
  PlotBigPoint(z, A);
  
  /* forward orbit of critical point  */
  for (i=1;i<iMax ; ++i)
    {
      z  = fc(z,C);
      //if (cabs2(z - z2a) > 2.0) {return 1;} // escaping
      PlotBigPoint(z, A);
    }
  

    
   
  return 0;
 
}


int Test(){


 complex double z = zcr;
 int i;
 int iMax = 100;
 
 printf(" |z-z1| = %f  \n", cabs(z-z1)); 
 	
	/* forward orbit of critical point  */
  for (i=1;i<iMax ; ++i)
    {
      z  = fc(z,C);
      printf("z = %f%+f \t |z-z1| = %f  \n", creal(z), cimag(z), cabs(z-z1)); 
 	
      
      //if (cabs2(z - z2a) > 2.0) {return 1;} // escaping
      
    }
    
    return 0;
  


}





// ***********************************************************************************************
// ********************** edge detection usung Sobel filter ***************************************
// ***************************************************************************************************

// from Source to Destination
int ComputeBoundaries(unsigned char S[], unsigned char D[])
{
 
  unsigned int iX,iY; /* indices of 2D virtual array (image) = integer coordinate */
  unsigned int i; /* index of 1D array  */
  /* sobel filter */
  unsigned char G, Gh, Gv; 
  // boundaries are in D  array ( global var )
 
  // clear D array
  memset(D, iColorOfExterior, iSize*sizeof(*D)); // for heap-allocated arrays, where N is the number of elements = FillArrayWithColor(D , iColorOfExterior);
 
  // printf(" find boundaries in S array using  Sobel filter\n");   
#pragma omp parallel for schedule(dynamic) private(i,iY,iX,Gv,Gh,G) shared(iyMax,ixMax)
  for(iY=1;iY<iyMax-1;++iY){ 
    for(iX=1;iX<ixMax-1;++iX){ 
      Gv= S[Give_i(iX-1,iY+1)] + 2*S[Give_i(iX,iY+1)] + S[Give_i(iX-1,iY+1)] - S[Give_i(iX-1,iY-1)] - 2*S[Give_i(iX-1,iY)] - S[Give_i(iX+1,iY-1)];
      Gh= S[Give_i(iX+1,iY+1)] + 2*S[Give_i(iX+1,iY)] + S[Give_i(iX-1,iY-1)] - S[Give_i(iX+1,iY-1)] - 2*S[Give_i(iX-1,iY)] - S[Give_i(iX-1,iY-1)];
      G = sqrt(Gh*Gh + Gv*Gv);
      i= Give_i(iX,iY); /* compute index of 1D array from indices of 2D array */
      if (G==0) {D[i]=255;} /* background */
      else {D[i]=0;}  /* boundary */
    }
  }
 
   
 
  return 0;
}



// copy from Source to Destination
int CopyBoundaries(unsigned char S[],  unsigned char D[])
{
 
  unsigned int iX,iY; /* indices of 2D virtual array (image) = integer coordinate */
  unsigned int i; /* index of 1D array  */
 
 
  //printf("copy boundaries from S array to D array \n");
  for(iY=1;iY<iyMax-1;++iY)
    for(iX=1;iX<ixMax-1;++iX)
      {i= Give_i(iX,iY); if (S[i]==0) D[i]=0;}
 
 
 
  return 0;
}

















// *******************************************************************************************
// ********************************** save A array to pgm file ****************************
// *********************************************************************************************

int SaveArray2PGMFile (unsigned char A[],  char * n, char *comment)
{

  FILE *fp;
  const unsigned int MaxColorComponentValue = 255;	/* color component is coded from 0 to 255 ;  it is 8 bit color file */
  char name[100];		/* name of file */
  snprintf (name, sizeof name, "%s", n );	/*  */
  char *filename = strcat (name, ".pgm");
  char long_comment[200];
  sprintf (long_comment, "fc(z)=z^2+z*c  %s", comment);





  // save image array to the pgm file 
  fp = fopen (filename, "wb");	// create new file,give it a name and open it in binary mode 
  fprintf (fp, "P5\n # %s\n %u %u\n %u\n", long_comment, iWidth, iHeight, MaxColorComponentValue);	// write header to the file
  size_t rSize = fwrite (A, sizeof(A[0]), iSize, fp);	// write whole array with image data bytes to the file in one step 
  fclose (fp);

  // info 
  if ( rSize == iSize) 
  	{
  		printf ("File %s saved ", filename);
  		if (long_comment == NULL || strlen (long_comment) == 0)
    		printf ("\n");
  			else { printf (". Comment = %s \n", long_comment); }
  	}
  	else {printf("wrote %zu elements out of %llu requested\n", rSize,  iSize);}

  return 0;
}




int PrintCInfo ()
{

  printf ("gcc version: %d.%d.%d\n", __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);	// https://stackoverflow.com/questions/20389193/how-do-i-check-my-gcc-c-compiler-version-for-my-eclipse
  // OpenMP version is displayed in the console : export  OMP_DISPLAY_ENV="TRUE"

  printf ("__STDC__ = %d\n", __STDC__);
  printf ("__STDC_VERSION__ = %ld\n", __STDC_VERSION__);
  printf ("c dialect = ");
  switch (__STDC_VERSION__)
    {				// the format YYYYMM 
    case 199409L:
      printf ("C94\n");
      break;
    case 199901L:
      printf ("C99\n");
      break;
    case 201112L:
      printf ("C11\n");
      break;
    case 201710L:
      printf ("C18\n");
      break;
      //default : /* Optional */

    }

  return 0;
}


int
PrintProgramInfo ()
{


  // display info messages
  printf ("Numerical approximation of Julia set for F(z,C) =  z^2 + z*c) \n");
  printf ("parameter C = ( %.16f ; %.16f ) \n", creal (C), cimag (C));
  printf ("Period  = %d  orbit : \n", period);
  printf ("\tfixed point z1 = ( %.16f ; %.16f ) \n", creal (z1), cimag (z1));
  //printf ("\tparameter z2b = ( %.16f ; %.16f ) \n", creal (z2b), cimag (z2b));
  
  

  printf ("Image Width = %f in world coordinate\n", ZxMax - ZxMin);
  printf ("PixelWidth = %.16f \n", PixelWidth);
  printf ("AR = %.16f = %f *PixelWidth = %f %% of ImageWidth \n", AR, AR / PixelWidth, AR / ZxMax - ZxMin);


  printf("pixel counters\n");
  printf ("\tuUnknown = %llu\n", uUnknown);
  printf ("\tuExterior = %llu\n", uExterior);
  printf ("\tuInterior = %llu\n", uInterior);
  printf ("Sum of pixels  = %llu\n", uInterior+uExterior + uUnknown);
  printf ("all pixels of the array = iSize = %llu\n", iSize);


  // image corners in world coordinate
  // center and radius
  // center and zoom
  // GradientRepetition
  printf ("Maximal number of iterations = iterMax = %d \n", IterMax);
  printf ("ratio of image  = %f ; it should be 1.000 ...\n", ratio);
  //




  return 0;
}



int SetPlane(complex double center, double radius, double a_ratio){

  ZxMin = creal(center) - radius*a_ratio;	
  ZxMax = creal(center) + radius*a_ratio;	//0.75;
  ZyMin = cimag(center) - radius;	// inv
  ZyMax = cimag(center) + radius;	//0.7;
  return 0;

}



// Check Orientation of z-plane image : mark first quadrant of complex plane 
// it should be in the upper right position
// uses global var :  ...
int CheckZPlaneOrientation(unsigned char A[] )
{
 
	double Zx, Zy; //  Z= Zx+ZY*i;
	unsigned i; /* index of 1D array */
	unsigned int ix, iy;		// pixel coordinate 
	
	fprintf(stderr, "compute image CheckOrientation\n");
 	// for all pixels of image 
	#pragma omp parallel for schedule(dynamic) private(ix,iy, i, Zx, Zy) shared(A, ixMax , iyMax) 
	for (iy = iyMin; iy <= iyMax; ++iy){
    		//fprintf (stderr, " %d from %d \r", iy, iyMax);	//info 
    		for (ix = ixMin; ix <= ixMax; ++ix){
    			// from screen to world coordinate 
    			Zy = GiveZy(iy);
    			Zx = GiveZx(ix);
	  		i = Give_i(ix, iy); /* compute index of 1D array from indices of 2D array */
	  		if (Zx>0 && Zy>0) A[i]=255-A[i];   // check the orientation of Z-plane by marking first quadrant */
    		}
    	}
   
   
  	return 0;
}







// *****************************************************************************
//;;;;;;;;;;;;;;;;;;;;;;  setup ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
// **************************************************************************************

int setup ()
{

  fprintf (stderr, "setup start\n");






  /* 2D array ranges */

  iWidth = iHeight* DisplayAspectRatio ;
  iSize = iWidth * iHeight;	// size = number of points in array 
  // iy
  iyMax = iHeight - 1;		// Indexes of array starts from 0 not 1 so the highest elements of an array is = array_name[size-1].
  //ix

  ixMax = iWidth - 1;

  /* 1D array ranges */
  // i1Dsize = i2Dsize; // 1D array with the same size as 2D array
  iMax = iSize - 1;		// Indexes of array starts from 0 not 1 so the highest elements of an array is = array_name[size-1].

  center = zcr;
  SetPlane( center, radius,  DisplayAspectRatio );	
  /* Pixel sizes */
  PixelWidth = (ZxMax - ZxMin) / ixMax;	//  ixMax = (iWidth-1)  step between pixels in world coordinate 
  PixelHeight = (ZyMax - ZyMin) / iyMax;
  ratio = ((ZxMax - ZxMin) / (ZyMax - ZyMin)) / ((double) iWidth / (double) iHeight);	// it should be 1.000 ...

  ER = 200.0; // 
  ER2 = ER*ER;
  AR_max = 5*PixelWidth*iWidth/2000.0 ; // adjust first number 
  // GiveTunedAR(const int i_Max, const complex double zcr, const double c, const double zp){
  AR = GiveTunedAR(200, C, AR_max);
  AR2 = AR * AR;
  //AR12 = AR/2.0;
  
  
    



  /* create dynamic 1D arrays for colors ( shades of gray ) */
  data = malloc (iSize * sizeof (unsigned char));

  edge = malloc (iSize * sizeof (unsigned char));
  if (data == NULL || edge == NULL)
    {
      fprintf (stderr, " Could not allocate memory");
      return 1;
    }





 


  fprintf (stderr, " end of setup \n");

  return 0;

}				// ;;;;;;;;;;;;;;;;;;;;;;;;; end of the setup ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;




int end ()
{


  fprintf (stderr, " allways free memory (deallocate )  to avoid memory leaks \n");	// https://en.wikipedia.org/wiki/C_dynamic_memory_allocation
  free (data);
  free(edge);


  PrintProgramInfo ();
  PrintCInfo ();
  return 0;

}

// ********************************************************************************************************************
/* -----------------------------------------  main   -------------------------------------------------------------*/
// ********************************************************************************************************************

int main ()
{
  setup ();

  //Test();
  
  DrawImage (data, Fatou);	// first find Fatou
  SaveArray2PGMFile (data,  "Fatou" , "Fatou ");
  
  
  ComputeBoundaries(data,edge);
  SaveArray2PGMFile (edge, "Fatou_b", "Boundaries of Fatou"); 
  
  CopyBoundaries(edge,data);
  SaveArray2PGMFile (data,  "Fatou_B", "Fatou with boundaries"); 
  
  
  DrawImage (data, LSM);	// first find Fatou
  SaveArray2PGMFile (data,  "LSM", "LSM");
  
  
  ComputeBoundaries(data,edge);
  SaveArray2PGMFile (edge, "LCM", "Level Curves Method = Boundaries of Level Sets"); 
  
  DrawForwardOrbit(zcr, 10, edge);
  SaveArray2PGMFile (edge, "LCM_cr", "LCM and critical orbit");  
  
  
  MarkTraps(data);
  MarkAttractors(data);
  SaveArray2PGMFile (data, "LSM_bt", "Fatou with boundaries and traps; "); 
  
   CheckZPlaneOrientation(data);
   SaveArray2PGMFile (data, "LSM_btm", "Fatou with boundaries and traps. First quadrant is marked"); 
   
  /*
  ComputeBoundaries(data,edge);
  SaveArray2PGMFile (edge, 1, "Boundaries of Fatou; name = iWidth_IterMax_n"); 
  
  CopyBoundaries(edge,data);
  SaveArray2PGMFile (data,  2, "Fatou with boundaries; name = iWidth_IterMax_n"); 
  
  
  	
  DrawFatouImageLSM (data, IterMax);	// first find Fatou
  SaveArray2PGMFile (data, 6, "Fatou LSM, name = iWidth_IterMax_n");
  
 
  
  CopyBoundaries(edge,data);
  SaveArray2PGMFile (data, 8, "LSM with boundaries; name = iWidth_IterMax_n"); 
  */
  
  end ();

  return 0;
}

bash source code

#!/bin/bash 
 
# script file for BASH 
# which bash
# save this file as d.sh
# chmod +x d.sh
# ./d.sh
# checked in https://www.shellcheck.net/




printf "make pgm files \n"
gcc d.c -lm -Wall -march=native -fopenmp

if [ $? -ne 0 ]
then
    echo ERROR: compilation failed !!!!!!
    exit 1
fi


export  OMP_DISPLAY_ENV="TRUE"
printf "display OMP info \n"

time ./a.out > a.txt

export  OMP_DISPLAY_ENV="FALSE"

printf "convert all pgm files to png using Image Magic convert \n"
# for all pgm files in this directory
for file in *.pgm ; do
  # b is name of file without extension
  b=$(basename "$file" .pgm)
  # convert  using ImageMagic
  convert "${b}".pgm -resize 2000x2000 "${b}".png
  echo "$file"
done


printf "delete all pgm files \n"
rm ./*.pgm

 
echo OK
# end


Make

all: 
	chmod +x d.sh
	./d.sh



Text output

 make


chmod +x d.sh
./d.sh
make pgm files 
display OMP info 

OPENMP DISPLAY ENVIRONMENT BEGIN
  _OPENMP = '201511'
  OMP_DYNAMIC = 'FALSE'
  OMP_NESTED = 'FALSE'
  OMP_NUM_THREADS = '8'
  OMP_SCHEDULE = 'DYNAMIC'
  OMP_PROC_BIND = 'FALSE'
  OMP_PLACES = ''
  OMP_STACKSIZE = '0'
  OMP_WAIT_POLICY = 'PASSIVE'
  OMP_THREAD_LIMIT = '4294967295'
  OMP_MAX_ACTIVE_LEVELS = '1'
  OMP_CANCELLATION = 'FALSE'
  OMP_DEFAULT_DEVICE = '0'
  OMP_MAX_TASK_PRIORITY = '0'
  OMP_DISPLAY_AFFINITY = 'FALSE'
  OMP_AFFINITY_FORMAT = 'level %L thread %i affinity %A'
  OMP_ALLOCATOR = 'omp_default_mem_alloc'
  OMP_TARGET_OFFLOAD = 'DEFAULT'
OPENMP DISPLAY ENVIRONMENT END
setup start
 end of setup 
compute image CheckOrientation
 allways free memory (deallocate )  to avoid memory leaks 


File LSM_a.pgm saved . Comment = fc(z)=z^3+c  Fatou with boundaries and traps; name = iWidth_IterMax_n 
File LSM_am.pgm saved . Comment = fc(z)=z^3+c  Fatou with boundaries and traps. First quadrant is marked 
Numerical approximation of Julia set for F(z,C) =  z^2 + z*c) 
parameter C = ( 0.0000000000000000 ; 0.7000000000000000 ) 
Period  = 1  orbit : 
	fixed point z1 = ( 0.0000000000000000 ; 0.0000000000000000 ) 
Image Width = 2.600000 in world coordinate
PixelWidth = 0.0001300065003250 
AR = 0.0000000000000000 = 0.000000 *PixelWidth = 1.300000 % of ImageWidth 
pixel counters
	uUnknown = 0
	uExterior = 418938082
	uInterior = 327235851
Sum of pixels  = 746173933
all pixels of the array = iSize = 400000000
Maximal number of iterations = iterMax = 100000 
ratio of image  = 1.000000 ; it should be 1.000 ...
gcc version: 10.3.0
__STDC__ = 1
__STDC_VERSION__ = 201710
c dialect = C18

real	7m31,286s
user	52m33,681s
sys	0m6,141s
convert all pgm files to png using Image Magic convert 
FatouAnd B.pgm
Fatou_b.pgm
Fatou.pgm
LCM_9.pgm
LCM_cr.pgm
LSM_9.pgm
LSM_am.pgm
LSM_a.pgm
delete all pgm files 
OK

References

  1. Dynamics in one complex variable: introductory lectures John W. Milnor

Captions

Julia set for z^2+0.7i*z

Items portrayed in this file

depicts

9 June 2021

image/png

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current12:59, 9 June 2021Thumbnail for version as of 12:59, 9 June 20212,000 × 2,000 (610 KB)Soul windsurferfile comment

The following page uses this file:

Metadata