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The Waikato Environment for Knowledge Analysis (WEKA), a machine
learning workbench. This is the stable version. Apart from bugfixes, this version
does not receive any other updates.
/*
* 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 3 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, see .
*/
/*
* FloatingPoint.java
* Copyright (C) 2002-2012 University of Waikato, Hamilton, New Zealand
*
*/
package weka.core.matrix;
import java.text.DecimalFormat;
import java.text.FieldPosition;
import weka.core.RevisionHandler;
import weka.core.RevisionUtils;
/**
* Class for the format of floating point numbers
*
* @author Yong Wang
* @version $Revision: 8034 $
*/
public class FloatingPointFormat
extends DecimalFormat
implements RevisionHandler {
/** for serialization */
private static final long serialVersionUID = 4500373755333429499L;
protected DecimalFormat nf ;
protected int width;
protected int decimal;
protected boolean trailing = true;
/**
* Default constructor
*/
public FloatingPointFormat () {
this( 8, 5 );
}
public FloatingPointFormat ( int digits ) {
this( 8, 2 );
}
public FloatingPointFormat( int w, int d ) {
width = w;
decimal = d;
nf = new DecimalFormat( pattern(w, d) );
nf.setPositivePrefix(" ");
nf.setNegativePrefix("-");
}
public FloatingPointFormat( int w, int d, boolean trailingZeros ) {
this( w, d );
this.trailing = trailingZeros;
}
public StringBuffer format(double number, StringBuffer toAppendTo,
FieldPosition pos) {
StringBuffer s = new StringBuffer( nf.format(number) );
if( s.length() > width ) {
if( s.charAt(0) == ' ' && s.length() == width + 1 ) {
s.deleteCharAt(0);
}
else {
s.setLength( width );
for( int i = 0; i < width; i ++ )
s.setCharAt(i, '*');
}
}
else {
for (int i = 0; i < width - s.length(); i++) // padding
s.insert(0,' ');
}
if( !trailing && decimal > 0 ) { // delete trailing zeros
while( s.charAt( s.length()-1 ) == '0' )
s.deleteCharAt( s.length()-1 );
if( s.charAt( s.length()-1 ) == '.' )
s.deleteCharAt( s.length()-1 );
}
return toAppendTo.append( s );
}
public static String pattern( int w, int d ) {
StringBuffer s = new StringBuffer(); // "-##0.00" // fw.d
s.append( padding(w - d - 3, '#') );
if( d == 0) s.append('0');
else {
s.append("0.");
s.append( padding( d, '0') );
}
return s.toString();
}
private static StringBuffer padding( int n, char c ) {
StringBuffer text = new StringBuffer();
for(int i = 0; i < n; i++ ){
text.append( c );
}
return text;
}
public int width () {
if( !trailing ) throw new RuntimeException( "flexible width" );
return width;
}
/**
* Returns the revision string.
*
* @return the revision
*/
public String getRevision() {
return RevisionUtils.extract("$Revision: 8034 $");
}
}