Draw Math Function Your Own : Math Functions « Advanced Graphics « Java






Draw Math Function Your Own

Draw Math Function Your Own
import java.awt.*;
import java.applet.*;

import graph.*;
/*
**************************************************************************
**
**                      Applet parse1d
**
**************************************************************************
**    Copyright (C) 1995, 1996 Leigh Brookshaw
**
**    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.
**
**    This program 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 this program; if not, write to the Free Software
**    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**************************************************************************
*
* This applet uses the ParseFunction class to parse an input string
* and plot the result.
*
*************************************************************************/

public class parse1d extends Applet {

      G2Dint graph         = new G2Dint();   // Graph class to do the plotting
      Axis xaxis;
      Axis yaxis;
      DataSet data;

      TextField pinput     = new TextField(5);       // Number of points 
      TextField mininput   = new TextField(10);      // Minimum x value input
      TextField maxinput   = new TextField(10);      // Maximum x value input
      TextField finput     = new TextField(30);      // Input for the function to plot
      Button plot          = new Button("Plot It!"); // Button to plot it.





      public void init() {
         Label title            = new Label("Function Parsing",Label.CENTER);
         Panel panel            = new Panel();
         GridBagLayout gridbag  = new GridBagLayout();
         GridBagConstraints  c  = new GridBagConstraints();
         Font font              = new Font("TimesRoman",Font.PLAIN,15);

         title.setFont(new Font("TimesRoman",Font.PLAIN,25));
          
         
         setLayout(new BorderLayout() );
         add("North",title);
         add("Center",panel);

         finput.setText("sin(x)"); 
         pinput.setText("1000"); 
         mininput.setText("0"); 
         maxinput.setText("20"); 


         
         
         panel.setLayout(gridbag);

         Label plabel   = new Label("Number of Points");         
         Label minlabel = new Label("Minimum x Value");
         Label maxlabel = new Label("Maximum x Value");
         Label flabel   = new Label("Function");
         
         plabel.setFont(font);
         flabel.setFont(font);
         minlabel.setFont(font);
         maxlabel.setFont(font);
         
         pinput.setFont(font);
         pinput.setBackground(Color.lightGray);
         finput.setFont(font);
         finput.setBackground(Color.lightGray);
         mininput.setFont(font);
         mininput.setBackground(Color.lightGray);
         maxinput.setFont(font);
         maxinput.setBackground(Color.lightGray);
         plot.setFont(font);
         plot.setBackground(Color.green);

         c.weightx = 1.0;
         c.weighty = 1.0;
         c.gridwidth = 3;
         c.gridwidth=GridBagConstraints.REMAINDER;
         c.fill  =  GridBagConstraints.BOTH;
         
         gridbag.setConstraints(graph,c);
         
         c.fill  =  GridBagConstraints.NONE;
         c.weightx=0.0;
         c.weighty=0.0;
         c.gridheight=1;
         
         c.gridwidth=1;
         c.anchor = GridBagConstraints.EAST;
         gridbag.setConstraints(flabel,c);
         
         c.anchor = GridBagConstraints.CENTER;
         c.gridwidth=GridBagConstraints.RELATIVE;
         c.fill  =  GridBagConstraints.HORIZONTAL;
         gridbag.setConstraints(finput,c);
         
         c.fill = GridBagConstraints.NONE;
         c.gridwidth=GridBagConstraints.REMAINDER;

         gridbag.setConstraints(plot,c);

         
         c.gridwidth=1;
         c.anchor = GridBagConstraints.EAST;
         gridbag.setConstraints(plabel,c);
         c.gridwidth=2;
         c.anchor = GridBagConstraints.WEST;
         c.gridwidth=GridBagConstraints.REMAINDER;
         gridbag.setConstraints(pinput,c);
         
         c.gridwidth=1;
         c.anchor = GridBagConstraints.EAST;
         gridbag.setConstraints(minlabel,c);
         c.gridwidth=2;
         c.anchor = GridBagConstraints.WEST;
         c.gridwidth=GridBagConstraints.REMAINDER;
         gridbag.setConstraints(mininput,c);
         
         c.gridwidth=1;
         c.anchor = GridBagConstraints.EAST;
         gridbag.setConstraints(maxlabel,c);
         c.gridwidth=2;
         c.anchor = GridBagConstraints.WEST;
         c.gridwidth=GridBagConstraints.REMAINDER;
         gridbag.setConstraints(maxinput,c);
         
         
         panel.add(graph);
         panel.add(flabel);
         panel.add(finput);
         panel.add(plot);
         panel.add(plabel);
         panel.add(pinput);
         panel.add(minlabel);
         panel.add(mininput);
         panel.add(maxlabel);
         panel.add(maxinput);

         
         xaxis = graph.createXAxis();
         xaxis.setTitleText("X");

         yaxis = graph.createYAxis();


         data = new DataSet();

         xaxis.attachDataSet(data);
         yaxis.attachDataSet(data);
         graph.attachDataSet(data);


         graph.setDataBackground(new Color(255,200,175));
         graph.setBackground(new Color(200,150,100));

         plot();

      }



      void plot() {
         int points;
         double maximum;
         double minimum;
         double x;
         int count = 0;
         boolean error = false;

         try {
              points   = Integer.parseInt(pinput.getText());
         } catch(Exception e) {
//              this.showStatus("Error with number of points!");
              System.out.println("Number of points error "+e.getMessage());
              return;
         }

         try {
            maximum = Double.valueOf(maxinput.getText()).doubleValue();
         } catch(Exception e) {
  //            this.showStatus("Error with X maximum value!");
              System.out.println("X maximum error "+e.getMessage());
              return;
         }

         try {
            minimum = Double.valueOf(mininput.getText()).doubleValue();
         } catch(Exception e) {
    //          this.showStatus("Error with X minimum value!");
              System.out.println("X minimum error "+e.getMessage());
              return;
         }

         ParseFunction function = new ParseFunction(finput.getText());

         if(!function.parse()) {
      //        this.showStatus("Failed to parse function!");
              System.out.println("Failed to parse function!");
              return;
         }

         double d[] = new double[2*points];

        // this.showStatus("Calculating points!");

         for(int i=0; i<points; i++) {

             x = minimum + i*(maximum-minimum)/(points-1);
             d[count] = x;
             try {
                  d[count+1] = function.getResult(x);
                  count += 2;
             } catch(Exception e) { error = true; }

         }
 

         if(count <= 2) {
//             this.showStatus("Error NO POINTS to PLOT!"); 
             System.out.println("Error NO POINTS to PLOT!");
             return;
         } else
         if( error ) {
  //           this.showStatus("Error while Calculating points!"); 
             System.out.println("Error while calculating points!");
   }


         yaxis.setTitleText(finput.getText());

         data.deleteData();

         try {
               data.append(d,count/2);
         } catch(Exception e) {
    //         this.showStatus("Error while appending data!"); 
             System.out.println("Error while appending data!");
             return;
   }
              

         graph.repaint();
      }



     public boolean action(Event e, Object a) {

         if(e.target instanceof Button) {
             if( plot.equals(e.target) ) {
                  plot();
                  return true;
             }
         }


         return false;
       }


      public static void main(String[] a){
         javax.swing.JFrame f = new javax.swing.JFrame();
         Applet app = new parse1d();
         app.init();
         
         f.getContentPane().add (app);

         f.pack();
         f.setSize (new Dimension (500, 500));
         f.setVisible(true);
      }

}





           
       








Graph-DrawMathFunctionYourOwn.zip( 242 k)

Related examples in the same category

1.Math Function ChartMath Function Chart
2.Draw Your Own Contour FunctionDraw Your Own Contour Function
3.Draw Math Function In CoordinateDraw Math Function In Coordinate
4.ContouringContouring
5.Display the graph of a single function of one variableDisplay the graph of a single function of one variable
6.DerivativesDerivatives
7.Function CompositionFunction Composition
8.Draw the functionDraw the function
9.Math function graph 1Math function graph 1
10.Draw math function on the coordinateDraw math function on the coordinate
11.Calculate the arithmetic functionCalculate the arithmetic function
12.Math function and barMath function and bar
13.Science Parser