root / trunk / libraries / libRaster / src / org / gvsig / raster / grid / GridStatistic.java @ 11200
History | View | Annotate | Download (2.93 KB)
1 | 10740 | nacho | /* gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana
|
---|---|---|---|
2 | *
|
||
3 | * Copyright (C) 2006 IVER T.I. and Generalitat Valenciana.
|
||
4 | *
|
||
5 | * This program is free software; you can redistribute it and/or
|
||
6 | * modify it under the terms of the GNU General Public License
|
||
7 | * as published by the Free Software Foundation; either version 2
|
||
8 | * of the License, or (at your option) any later version.
|
||
9 | *
|
||
10 | * This program is distributed in the hope that it will be useful,
|
||
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
13 | * GNU General Public License for more details.
|
||
14 | *
|
||
15 | * You should have received a copy of the GNU General Public License
|
||
16 | * along with this program; if not, write to the Free Software
|
||
17 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,USA.
|
||
18 | */
|
||
19 | package org.gvsig.raster.grid; |
||
20 | |||
21 | 11076 | nacho | import org.gvsig.raster.buffer.RasterBufferInvalidAccessException; |
22 | 10740 | nacho | |
23 | |||
24 | /**
|
||
25 | * Estadisticas de un grid
|
||
26 | * @author Victor Olaya (volaya@ya.com)
|
||
27 | * @author Nacho Brodin (nachobrodin@gmail.com)
|
||
28 | */
|
||
29 | public class GridStatistic { |
||
30 | private double max; |
||
31 | private double min; |
||
32 | private double mean; |
||
33 | private double variance; |
||
34 | private boolean statisticsCalculated = false; |
||
35 | private Grid grid = null; |
||
36 | |||
37 | public GridStatistic(Grid grid){
|
||
38 | this.grid = grid;
|
||
39 | } |
||
40 | |||
41 | public void calculateStatistics() throws RasterBufferInvalidAccessException{ |
||
42 | int x, y;
|
||
43 | double z;
|
||
44 | int iValues;
|
||
45 | |||
46 | mean = 0.0;
|
||
47 | variance = 0.0;
|
||
48 | iValues = 0;
|
||
49 | |||
50 | statisticsCalculated = true;
|
||
51 | |||
52 | for (y = 0; y < grid.getNY(); y++){ |
||
53 | for (x = 0; x < grid.getNX(); x++){ |
||
54 | z = grid.getCellValueAsDouble(x,y); |
||
55 | if( !grid.isNoDataValue(z)) {
|
||
56 | if( iValues == 0 ) |
||
57 | min = max = z; |
||
58 | else if( min > z ) |
||
59 | min = z; |
||
60 | else if( max < z ) |
||
61 | max = z; |
||
62 | |||
63 | mean += z; |
||
64 | variance += z * z; |
||
65 | iValues++; |
||
66 | } |
||
67 | } |
||
68 | } |
||
69 | |||
70 | if( iValues > 0 ){ |
||
71 | mean /= (double) iValues;
|
||
72 | variance = variance / (double) iValues - mean * mean;
|
||
73 | } |
||
74 | statisticsCalculated = true;
|
||
75 | } |
||
76 | |||
77 | /**
|
||
78 | * Obtiene el valor m?ximo del grid
|
||
79 | * @return Valor m?ximo
|
||
80 | */
|
||
81 | public double getMax() { |
||
82 | return max;
|
||
83 | } |
||
84 | |||
85 | /**
|
||
86 | * Obtiene el valor m?dio del grid
|
||
87 | * @return Valor medio
|
||
88 | */
|
||
89 | public double getMean() { |
||
90 | return mean;
|
||
91 | } |
||
92 | |||
93 | /**
|
||
94 | * Obtiene el valor m?ximo del grid
|
||
95 | * @return Valor m?nimo
|
||
96 | */
|
||
97 | public double getMin() { |
||
98 | return min;
|
||
99 | } |
||
100 | |||
101 | /**
|
||
102 | * Consulta si las estadisticas han sido calculadas o no.
|
||
103 | * @return true si las estadisticas del grid est?n calculadas y false si no lo est?n
|
||
104 | */
|
||
105 | public boolean isStatisticsCalculated() { |
||
106 | return statisticsCalculated;
|
||
107 | } |
||
108 | |||
109 | /**
|
||
110 | * Asigna el flag que informa si las estadisticas est?n calculadas para un grid concreto
|
||
111 | * @param calc true si est?n calculadas y false si no lo est?n
|
||
112 | */
|
||
113 | public void setStatisticsCalculated(boolean calc){ |
||
114 | this.statisticsCalculated = calc;
|
||
115 | } |
||
116 | |||
117 | /**
|
||
118 | * Obtiene la varianza
|
||
119 | * @return Varianza
|
||
120 | */
|
||
121 | public double getVariance() { |
||
122 | return variance;
|
||
123 | } |
||
124 | } |