PURPOSE: calculate new coordinate vectors for an original grid to be
resampled to new cellsize .
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USAGE: [XI,YI] = get_coordinates(X, Y, targetcellsize);
where: [X,Y] are the coordinates vectors of the input grid
[targetcellsize] is the target cellsize the new grid shall be resampled to
RETURNS:
[XI],[YI] = the x and y coordinate vectors of the new resampled
grid
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NOTES: All coordinates used are lower left corner coordinates! New matrix
has no of rows and cols that sum up to either same size or less than
original grid. If extent does not match, rows and cols are rounded
down. (rounding errors might cut 1 row/col!) Counting from llc.
See also: grid2mat(), mat2grid()
Felix Hebeler, Geography Dept., University Zurich, March 2006.0001 function [XI,YI] = get_coordinates(X, Y, targetcellsize) 0002 % PURPOSE: calculate new coordinate vectors for an original grid to be 0003 % resampled to new cellsize . 0004 % ------------------------------------------------------------------- 0005 % USAGE: [XI,YI] = get_coordinates(X, Y, targetcellsize); 0006 % where: [X,Y] are the coordinates vectors of the input grid 0007 % [targetcellsize] is the target cellsize the new grid shall be resampled to 0008 % RETURNS: 0009 % [XI],[YI] = the x and y coordinate vectors of the new resampled 0010 % grid 0011 % ------------------------------------------------------------------- 0012 % NOTES: All coordinates used are lower left corner coordinates! New matrix 0013 % has no of rows and cols that sum up to either same size or less than 0014 % original grid. If extent does not match, rows and cols are rounded 0015 % down. (rounding errors might cut 1 row/col!) Counting from llc. 0016 % 0017 % See also: grid2mat(), mat2grid() 0018 % 0019 % Felix Hebeler, Geography Dept., University Zurich, March 2006. 0020 xll = min(X); 0021 yll = min(Y); 0022 cols = size(X,2); 0023 rows = size(Y,2); 0024 xcs=abs(X(1)-X(2)); 0025 ycs=abs(Y(1)-Y(2)); 0026 0027 ncols = round(cols*xcs/targetcellsize); 0028 nrows = round(rows*ycs/targetcellsize); 0029 %ncols = floor(cols*cellsize/targetcellsize); 0030 %nrows = floor(rows*cellsize/targetcellsize); 0031 0032 0033 % construct index vectors of llc coords 0034 XI = xll + (0.5*targetcellsize) + [0:targetcellsize:(ncols-1)*targetcellsize]; 0035 YI = yll + (0.5*targetcellsize) + [0:targetcellsize:(nrows-1)*targetcellsize]; ny=ny(end:-1:1); 0036 0037