A program to plot polar equations

mproc

Hello All !

I wrote this program to plot polar equations. For demonstration, I have plotted two equations. You can control various parameters like curve equations, line thickness, line color, background color, etc. Kindly give your feedback and suggestions. You can use it for your work, if you like...

Many Thanks!

float t=0,w,h;
float r=0,theta=0,r1=0;

void setup(){

  fullScreen();
  background(255);

  h=height;
  w=width;

  /** DRAWING THE CO-ORDINATE AXES */
  strokeWeight(1);
  stroke(0);
  line(0,h/2,w,h/2);
  line(w/2,0,w/2,h);

  /** LINE THICKNESS */
  strokeWeight(3);
}

void draw(){

  /** SHIFTING THE ORIGIN TO CENTER OF THE SCREEN */
  translate(w/2,h/2);

  /** ROTATING TO THE POLAR ANGLE */
  theta=radians(t);
  rotate(theta);

  /** EQUATIONS FOR THE TWO CURVES */
  r=150*sqrt(sin(3*theta));
  r1=100+150*(sin(theta));

  /** PLOTTING THE FIRST CURVE */
  stroke(255,0,0);
  point(-r,0);

  /** PLOTTING THE SECOND CURVE */
  stroke(0,0,255);
  point(-r1,0);

  t+=0.25;
}

jeremydouglass

@mproc -- thank you so much for sharing this work! Very concise.

For a related discussion of cartesian plotting, see:

• https://forum.processing.org/two/discussion/19180/plot-graph

Note in particular the discussion at the end of the thread of point() vs. line() vs. PShape approaches to rendering. One of these alternate approaches might enable your red curve to be more connected as it approaches 0,0.

mproc

@jeremydouglas Thanks, but to understand your code is very difficult for me. I am just starting out with processing...

nabr

nice