cdm/src/main/java/ucar/nc2/ft2/coverage/adapter/GeoGridCoordinate2D.java
private boolean box9(double wantLat, double wantLon, int[] rectIndex) {
    int row = rectIndex[0];
    int minrow = Math.max(row-1, 0);
    int maxrow = Math.min(row+1, nrows);

    int col = rectIndex[1];
    int mincol= Math.max(col-1, 0);
    int maxcol = Math.min(col+1, ncols);

    if (debug) System.out.printf("%n   box9:");
    for (int i=minrow; i<=maxrow; i++)
      for (int j=mincol; j<=maxcol; j++) {
        rectIndex[0] = i;
        rectIndex[1] = j;
        if (contains(wantLat, wantLon,  rectIndex)) return true;
      }

    return false;
  }
private boolean box9(double wantLat, double wantLon, int[] rectIndex) {
    int row = rectIndex[0];
    int minrow = Math.max(row-1, 0);
    int maxrow = Math.min(row+1, nrows);

    int col = rectIndex[1];
    int mincol= Math.max(col-1, 0);
    int maxcol = Math.min(col+1, ncols);

    if (debug) System.out.printf("%n   box9:");
    for (int i=minrow; i<=maxrow; i++)
      for (int j=mincol; j<=maxcol; j++) {
        rectIndex[0] = i;
        rectIndex[1] = j;
        if (contains(wantLat, wantLon,  rectIndex)) return true;
      }

    return false;
  }
we think its got to be in one of the 9 boxes around rectIndex