package org.lcsim.recon.tracking.magfield;
   
   import java.io.BufferedInputStream;
   import java.io.BufferedReader;
   import java.io.InputStream;
   import java.io.InputStreamReader;
   import java.util.StringTokenizer;
   import junit.framework.TestCase;
   import org.lcsim.recon.tracking.spacegeom.CartesianPoint;
  import org.lcsim.recon.tracking.spacegeom.SpacePoint;
  import org.lcsim.recon.tracking.spacegeom.SpacePointVector;
  import static java.lang.Math.abs;
  
  /**
   *
   * @author Norman A Graf
   *
   * @version $Id:
   */
  public class Cartesian3DMagneticFieldMapTest extends TestCase
  {
  
      private boolean debug = false;
  
      public void testCartesian3DMagneticFieldMap() throws Exception
      {
          InputStream is = this.getClass().getResourceAsStream("ThreeDFieldMap.dat");
          double xOff = 0.0;
          double yOff = 0.0;
          double zOff = 0.0;
          Cartesian3DMagneticFieldMap map = new Cartesian3DMagneticFieldMap(is, xOff, yOff, zOff);
  
          is.close();
          // now read in field map again, and check that we get the correct values at the
          // measured points
          // does not test the interpolation per se but is a check.
          BufferedReader myInput = new BufferedReader(new InputStreamReader(new BufferedInputStream(this.getClass().getResourceAsStream("ThreeDFieldMap.dat"))));
          String thisLine;
          int nx = 0;
          int ny = 0;
          int nz = 0;
          //skip the first nine lines of metadata
          for (int i = 0; i < 9; ++i) {
              thisLine = myInput.readLine();
              if (i == 1) // parse for number of grid point in x, y,x
              {
                  StringTokenizer st = new StringTokenizer(thisLine, " ");
                  nx = Integer.parseInt(st.nextToken());
                  ny = Integer.parseInt(st.nextToken());
                  nz = Integer.parseInt(st.nextToken());
              }
          }
          assertEquals(nx, 6);
          assertEquals(ny, 6);
          assertEquals(nz, 10);
  
          int nlines = nx * ny * nz;
          // loop over the field points
  
          for (int i = 0; i < nlines; ++i) {
              thisLine = myInput.readLine();
              StringTokenizer st = new StringTokenizer(thisLine, " ");
              double x = Double.parseDouble(st.nextToken());
              double y = Double.parseDouble(st.nextToken());
              double z = Double.parseDouble(st.nextToken());
              double bx = Double.parseDouble(st.nextToken());
              double by = Double.parseDouble(st.nextToken());
              double bz = Double.parseDouble(st.nextToken());
              SpacePointVector spv = map.field(new CartesianPoint(x+xOff, y+yOff, z+zOff));
              assertEquals(bx, spv.v_x(), abs(.001 * bx));
              assertEquals(by, spv.v_y(), abs(.001 * by));
              assertEquals(bz, spv.v_z(), abs(.001 * bz));
          }
      }
  }