Application: gvSIG desktop » gvSIG tools: ToolBox

package es.unex.sextante.hydrology.cFactorFromNDVI;

import es.unex.sextante.additionalInfo.AdditionalInfoNumericalValue;

import es.unex.sextante.core.GeoAlgorithm;

import es.unex.sextante.core.Sextante;

import es.unex.sextante.dataObjects.IRasterLayer;

import es.unex.sextante.exceptions.GeoAlgorithmExecutionException;

import es.unex.sextante.exceptions.RepeatedParameterNameException;

public class CFactorFromNDVIAlgorithm

         extends

            GeoAlgorithm {

   public static final String ALPHA   = "ALPHA";

   public static final String BETA    = "BETA";

   public static final String NDVI    = "NDVI";

   public static final String CFACTOR = "CFACTOR";

   private IRasterLayer       m_NDVI  = null;

   private IRasterLayer       m_CFactor;

   @Override

   public boolean processAlgorithm() throws GeoAlgorithmExecutionException {

      int x, y;

      int iNX, iNY;

      double dNDVI;

      double dAlpha, dBeta;

      m_NDVI = m_Parameters.getParameterValueAsRasterLayer(NDVI);

      m_CFactor = getNewRasterLayer(CFACTOR, "C", IRasterLayer.RASTER_DATA_TYPE_FLOAT);

      dAlpha = m_Parameters.getParameterValueAsDouble(ALPHA);

      dBeta = m_Parameters.getParameterValueAsDouble(BETA);

      m_NDVI.setWindowExtent(m_AnalysisExtent);

      iNX = m_NDVI.getNX();

      iNY = m_NDVI.getNY();

      for (y = 0; (y < iNY) && setProgress(y, iNY); y++) {

         for (x = 0; x < iNX; x++) {

            dNDVI = m_NDVI.getCellValueAsDouble(x, y);

            if (m_NDVI.isNoDataValue(dNDVI)) {

               m_CFactor.setNoData(x, y);

            }

            else {

               m_CFactor.setCellValue(x, y, Math.exp(-dAlpha * dNDVI / (dBeta - dNDVI)));

            }

         }

      }

      return !m_Task.isCanceled();

   }

   @Override

   public void defineCharacteristics() {

      setName(Sextante.getText("C_factor_from_NDVI"));

      setGroup(Sextante.getText("Indices_and_other_hydrological_parameters"));

      setUserCanDefineAnalysisExtent(true);

      try {

         m_Parameters.addInputRasterLayer(NDVI, "NDVI", true);

         m_Parameters.addNumericalValue(ALPHA, "Alpha", 1., AdditionalInfoNumericalValue.NUMERICAL_VALUE_DOUBLE);

         m_Parameters.addNumericalValue(BETA, "Beta", 2., AdditionalInfoNumericalValue.NUMERICAL_VALUE_DOUBLE);

         addOutputRasterLayer(CFACTOR, Sextante.getText("C"));

      }

      catch (final RepeatedParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

   }

}