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| Listing 36. PlotALot02.java. |
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/*File PlotALot02.java
Copyright 2005, R.G.BaldwinThis program is an update to the program named
PlotALot01. This program is designed to plotlarge amounts of time-series data for two
channels on the same axes. One set of data isplotted using the color black. The other set of
data is plotted using the color red. SeePlotALot01.java for a one-channel program.
Note that by carefully adjusting the plottingparameters, this program could also be used to
plot large quantities of spectral data in awaterfall display.
The class provides a main method so that theclass can be run as an application to test
itself.There are three steps involved in the use of this
class for plotting time series data:1. Instantiate a plotting object of type
PlotALot02 using one of two overloadedconstructors.
2. Feed pairs of data values that are to beplotted to the plotting object by calling the
feedData method once for each pair of datavalues. The first value in the pair will be
plotted in black. The second value in thepair will be plotted in red.
3. call one of two overloaded plotData methodson the plotting object once all of the data
has been fed to the object. This causes allof the data to be plotted.A using program can instantiate as many plotting
objects as are needed to plot all of thedifferent pairs of time series that need to be
plotted. Each plotting object can be used toplot as many pairs of data values as need be
plotted until the program runs out of availablememory.
The plotting object of type PlotALot02 owns oneor more Page objects that extend the Frame class.
The plotting object can own as many Page objectsas are necessary to plot all of the pairs of data
that are fed to that plotting object.The program produces a graphic output consisting
of a stack of Page objects on the screen, withthe data plotted on a Canvas object contained by
the Page object. The Page showing the earliestdata is on the top of the stack and the Page
showing the latest data is on the bottom of thestack. The Page objects on the top of the stack
must be physically moved in order to see thePage objects on the bottom of the stack.
Each Page object contains one or more horizontalaxes on which the data is plotted. The two time
series are superimposed on the same axes with thedata from one time series being plotted in black
and the data from the other time series beingplotted in red.
The earliest data is plotted on the axis nearestthe top of the Page moving from left to right
across the horizontal axis. Positive data valuesare plotted above the axis and negative values
are plotted below the axis. When the right endof an axis is reached, the next data value is
plotted on the left end of the axis immediatelybelow it. When the right end of the last axis on
the Page is reached, a new Page object is createdand the next data value is plotted at the left
end of the top axis on that new Page object.A mentioned above, there are two overloaded
versions of the constructor for the PlotALot02class. One overloaded version accepts several
incoming parameters allowing the user to controlvarious aspects of the plotting format. A second
overloaded version accepts a title string onlyand sets all of the plotting parameters to
default values. You can easily modify thesedefault values and recompile the class if you
prefer different default values.The parameters for the version of the constructor
that accepts plotting format information are:String title: Title for the Frame object. This
title isconcatenated with the page number and
the result appears in the banner at the top ofthe Frame.
int frameWidth:The Frame width in pixels.int frameHeight: The Frame height in pixels.
int traceSpacing: Distance between trace axes inpixels.
int sampSpace: Number of pixels dedicated to eachdata sample in pixels per sample. Must be 1 or
greater.int ovalWidth: Width of an oval that is used to
mark each sample value on the plot.int ovalHeight: Height of an oval that is used to
mark each sample value on the plot.For test purposes, the main method instantiates a
single plotting object and feeds two time seriesto that plotting object. Plotting parameters are
specified for the plotting object by using theoverloaded version of the constructor that
accepts plotting parameters.The data that is fed to the plotting object is
white random noise. One of the time series isthe sequence of values obtained from a random
number generator. The other time series is thesame as the first except that the sign of each
data values are reversed.Fifteen of the data values for each time series
are not random. Seven of the values for thefirst time series are set to values of 0,0,25,-25,
25,0,0. The corresponding seven values for thesecond time series are set to the same values
with sign reversal. This is done to confirm theproper transition from the end of one page to the
beginning of the next page.In addition, eight of the values for the first
time series are set to 0,0,20,20,-20,-20,0,0.The corresponding values for the second time
series are set to the same values with signreversal. This is done in order to confirm the
proper transition from one trace to the nexttrace on the same page.
These specific values and the locations in thedata where they are placed provide visible
confirmation that the transitions mentioned aboveare handled correctly. Note, however that these
are the correct locations for an AWT Frame objectunder WinXP. A Frame may have different inset
values under other operating systems, which maycause these specific locations to be incorrect
for that operating system. In that case, thevalues will be plotted but they won't confirm
the proper transition.The following information about the plotting
parameters is displayed on the command linescreen when the class is used for plotting. The
values shown below result from the execution ofthe main method of the class for test purposes.
Title: AFrame width: 158
Frame height: 237Page width: 150
Page height: 210Trace spacing: 36
Sample spacing: 5Traces per page: 5
Samples per page: 150There are two overloaded versions of the plotData
method. One version allows the user to specifythe location on the screen where the stack of
plotted pages will appear. This version requirestwo parameters, which are coordinate values in
pixels. The first parameter specifies thehorizontal coordinate of the upper left corner of
the stack of pages relative to the upper leftcorner of the screen. The second parameter
specifies the vertical coordinate of the upperleft corner of the stack of pages relative to the
upper left corner of the screen. Specifyingcoordinate values of 0,0 causes the stack to be
located in the upper left corner of the screen.The other overloaded version of plotData places
the stack of pages in the upper left corner ofthe screen by default. The main method in this
class uses the second version causing the stackof pages to appear in the upper left corner of
the screen by default.Each page has a WindowListener that willterminate the program if the user clicks the
close button on the Frame.The program was tested using J2SE 5.0 and WinXP.
Requires J2SE 5.0 to support generics.************************************************/
import java.awt.*;import java.awt.event.*;
import java.util.*;public class PlotALot02{
//This main method is provided so that the// class can be run as an application to test
// itself.public static void main(String[] args){//Instantiate a plotting object using the
// version of the constructor that allows for// controlling the plotting parameters.
PlotALot02 plotObjectA =new PlotALot02("A",158,237,36,5,4,4);//Feed pairs of data values to the plotting
// object.for(int cnt = 0;cnt<275;cnt++){
//Plot some white random noise Note that// fifteen of the values for each time
// series are not random. See the opening// comments for a discussion of the reasons
// why. Cause the values for the second// time series to be the negative of the
// values for the first time series.double valBlack = (Math.random() - 0.5)*25;
double valRed = -valBlack;//Feed pairs of values to the plotting
// object by calling the feedData method// once for each pair of data values.
if(cnt == 147){plotObjectA.feedData(0,0);
}else if(cnt == 148){plotObjectA.feedData(0,0);
}else if(cnt == 149){plotObjectA.feedData(25,-25);
}else if(cnt == 150){plotObjectA.feedData(-25,25);
}else if(cnt == 151){plotObjectA.feedData(25,-25);
}else if(cnt == 152){plotObjectA.feedData(0,0);
}else if(cnt == 153){plotObjectA.feedData(0,0);
}else if(cnt == 26){plotObjectA.feedData(0,0);
}else if(cnt == 27){plotObjectA.feedData(0,0);
}else if(cnt == 28){plotObjectA.feedData(20,-20);
}else if(cnt == 29){plotObjectA.feedData(20,-20);
}else if(cnt == 30){plotObjectA.feedData(-20,20);
}else if(cnt == 31){plotObjectA.feedData(-20,20);
}else if(cnt == 32){plotObjectA.feedData(0,0);
}else if(cnt == 33){plotObjectA.feedData(0,0);
}else{plotObjectA.feedData(valBlack,valRed);
}//end else}//end for loop
//Cause the data to be plotted in the default// screen location.
plotObjectA.plotData();}//end main
//-------------------------------------------//String title;
int frameWidth;int frameHeight;
int traceSpacing;//pixels between tracesint sampSpacing;//pixels between samples
int ovalWidth;//width of sample marking ovalint ovalHeight;//height of sample marking ovalint tracesPerPage;
int samplesPerPage;int pageCounter = 0;
int sampleCounter = 0;ArrayList<Page>pageLinks =
new ArrayList<Page>();//There are two overloaded versions of the
// constructor for this class. This// overloaded version accepts several incoming
// parameters allowing the user to control// various aspects of the plotting format. A
// different overloaded version accepts a title// string only and sets all of the plotting
// parameters to default values.PlotALot02(String title,//Frame title
int frameWidth,//in pixelsint frameHeight,//in pixels
int traceSpacing,//in pixelsint sampSpace,//in pixels per sample
int ovalWidth,//sample marker widthint ovalHeight)//sample marker hite
{//constructor//Specify sampSpace as pixels per sample.
// Should never be less than 1. Convert to// pixels between samples for purposes of
// computation.this.title = title;
this.frameWidth = frameWidth;this.frameHeight = frameHeight;
this.traceSpacing = traceSpacing;//Convert to pixels between samples.
this.sampSpacing = sampSpace - 1;this.ovalWidth = ovalWidth;
this.ovalHeight = ovalHeight;//The following object is instantiated solely
// to provide information about the width and// height of the canvas. This information is
// used to compute a variety of other// important values.
Page tempPage = new Page(title);int canvasWidth = tempPage.canvas.getWidth();
int canvasHeight =tempPage.canvas.getHeight();
//Display information about this plotting// object.
System.out.println("\nTitle: " +title);
System.out.println("Frame width: " + tempPage.getWidth());
System.out.println("Frame height: " + tempPage.getHeight());
System.out.println("Page width: " + canvasWidth);
System.out.println("Page height: " + canvasHeight);
System.out.println("Trace spacing: " + traceSpacing);
System.out.println("Sample spacing: " + (sampSpacing + 1));
if(sampSpacing<0){
System.out.println("Terminating");System.exit(0);
}//end if//Get rid of this temporary page.
tempPage.dispose();//Now compute the remaining important values.
tracesPerPage =(canvasHeight - traceSpacing/2)/
traceSpacing;System.out.println("Traces per page: "
+ tracesPerPage);if(tracesPerPage == 0){
System.out.println("Terminating program");System.exit(0);
}//end ifsamplesPerPage = canvasWidth * tracesPerPage/
(sampSpacing + 1);System.out.println("Samples per page: "
+ samplesPerPage);//Now instantiate the first usable Page
// object and store its reference in the// list.
pageLinks.add(new Page(title));}//end constructor
//-------------------------------------------//PlotALot02(String title){//call the other overloaded constructor
// passing default values for all but the// title.
this(title,400,410,50,2,2,2);}//end overloaded constructor
//-------------------------------------------////call this method once for each pair of data// values to be plotted.
void feedData(double valBlack,double valRed){if((sampleCounter) == samplesPerPage){
//if the page is full, increment the page// counter, create a new empty page, and
// reset the sample counter.pageCounter++;
sampleCounter = 0;pageLinks.add(new Page(title));
}//end if//Store the sample values in the MyCanvas
// object to be used later to paint the// screen. Then increment the sample
// counter. The sample values pass through// the page object into the current MyCanvas
// object.pageLinks.get(pageCounter).putData(
valBlack,valRed,sampleCounter);sampleCounter++;
}//end feedData//-------------------------------------------////There are two overloaded versions of the
// plotData method. One version allows the// user to specify the location on the screen
// where the stack of plotted pages will// appear. The other version places the stack
// in the upper left corner of the screen.//call one of the overloaded versions of// this method once when all data has been fed
// to the plotting object in order to rearrange// the order of the pages with page 0 at the
// top of the stack on the screen.//For this overloaded version, specify xCoor// and yCoor to control the location of the
// stack on the screen. Values of 0,0 will// place the stack at the upper left corner of
// the screen. Also see the other overloaded// version, which places the stack at the upper
// left corner of the screen by default.void plotData(int xCoor,int yCoor){
Page lastPage =pageLinks.get(pageLinks.size() - 1);
//Delay until last page becomes visible.while(!lastPage.isVisible()){
//Loop until last page becomes visible}//end while loopPage tempPage = null;
//Make all pages invisiblefor(int cnt = 0;cnt<(pageLinks.size());
cnt++){tempPage = pageLinks.get(cnt);
tempPage.setVisible(false);}//end for loop//Now make all pages visible in reverse order
// so that page 0 will be on top of the// stack on the screen.
for(int cnt = pageLinks.size() - 1;cnt>= 0;
cnt--){tempPage = pageLinks.get(cnt);
tempPage.setLocation(xCoor,yCoor);tempPage.setVisible(true);
}//end for loop}//end plotData(int xCoor,int yCoor)
//-------------------------------------------////This overloaded version of the method causes// the stack to be located in the upper left
// corner of the screen by defaultvoid plotData(){
plotData(0,0);//call overloaded version}//end plotData()
//-------------------------------------------////Inner class. A PlotALot02 object may
// have as many Page objects as are required// to plot all of the data values. The
// reference to each Page object is stored// in an ArrayList object belonging to the
// PlotALot02 object.class Page extends Frame{
MyCanvas canvas;int sampleCounter;
Page(String title){//constructorcanvas = new MyCanvas();
add(canvas);setSize(frameWidth,frameHeight);
setTitle(title + " Page: " + pageCounter);setVisible(true);//---------------------------------------//
//Anonymous inner class to terminate the// program when the user clicks the close
// button on the Frame.addWindowListener(
new WindowAdapter(){public void windowClosing(
WindowEvent e){System.exit(0);//terminate program
}//end windowClosing()}//end WindowAdapter
);//end addWindowListener//---------------------------------------//
}//end constructor//=========================================////This method receives a pair of sample
// values of type double and stores each of// them in a separate array object belonging
// to the MyCanvas object.void putData(double valBlack,double valRed,
int sampleCounter){canvas.blackData[sampleCounter] = valBlack;canvas.redData[sampleCounter] = valRed;//Save the sample counter in an instance
// variable to make it available to the// overridden paint method. This value is
// needed by the paint method so it will// know how many samples to plot on the
// final page which probably won't be full.this.sampleCounter = sampleCounter;
}//end putData//=========================================////Inner class
class MyCanvas extends Canvas{double [] blackData =new double[samplesPerPage];double [] redData =new double[samplesPerPage];//Override the paint methodpublic void paint(Graphics g){
//Draw horizontal axes, one for each// trace.
for(int cnt = 0;cnt<tracesPerPage;
cnt++){g.drawLine(0,
(cnt+1)*traceSpacing,this.getWidth(),
(cnt+1)*traceSpacing);}//end for loop//Plot the points if there are any to be
// plotted.if(sampleCounter>0){
for(int cnt = 0;cnt<= sampleCounter;
cnt++){//Compute a vertical offset to locate
// the data on a particular trace.int yOffset =
(1 + cnt*(sampSpacing + 1)/this.getWidth())*traceSpacing;
//Begin by plotting the values from// the blackData array object.
//Draw an oval centered on the sample// value to mark the sample in the
// plot. It is best if the dimensions// of the oval are evenly divisible
// by 2 for centering purposes.//Reverse the sign of the sample
// value to cause positive sample// values to be plotted above the
// axis.g.setColor(Color.BLACK);
g.drawOval(cnt*(sampSpacing + 1)%this.getWidth() - ovalWidth/2,
yOffset - (int)blackData[cnt]- ovalHeight/2,
ovalWidth,ovalHeight);//Connect the sample values with
// straight lines. Do not draw a// line connecting the last sample in
// one trace to the first sample in// the next trace.
if(cnt*(sampSpacing + 1)%this.getWidth()>=
sampSpacing + 1){g.drawLine(
(cnt - 1)*(sampSpacing + 1)%this.getWidth(),
yOffset - (int)blackData[cnt-1],
cnt*(sampSpacing + 1)%this.getWidth(),
yOffset - (int)blackData[cnt]);
}//end if//Now plot the data stored in the// redData array object.
g.setColor(Color.RED);//Draw the ovals as described above.
g.drawOval(cnt*(sampSpacing + 1)%this.getWidth() - ovalWidth/2,
yOffset - (int)redData[cnt]- ovalHeight/2,ovalWidth,
ovalHeight);//Connect the sample values with// straight lines as described above.
if(cnt*(sampSpacing + 1)%this.getWidth()>=
sampSpacing + 1){g.drawLine(
(cnt - 1)*(sampSpacing + 1)%this.getWidth(),
yOffset - (int)redData[cnt-1],
cnt*(sampSpacing + 1)%this.getWidth(),
yOffset - (int)redData[cnt]);}//end if
}//end for loop}//end if for sampleCounter>0
}//end overridden paint method}//end inner class MyCanvas
}//end inner class Page}//end class PlotALot02
//=============================================// |
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