free grads

amaxlocx()

This function returns the X location of maximum grid value over a spatial domain. The syntax is:

amaxlocx(expr, xdim1, xdim2, ydim1, ydim2)

 where:

expr    any valid grads grid expression 
xdim1   starting X or LON dimension expression 
xdim2   ending X or LON dimension expression 
ydim1   starting Y or LAT dimension expression 
ydim2   ending Y or LAT dimension expression 

For the X location of the global maximum, a shorthand may be used:

amaxlocx(expr, global) or 
amaxlocx(expr, g)

amaxlocx(expr, lon=0, lon=360, lat=-90, lat=90)

Usage Notes

1. This function will only work with grads version 2.0.2 or later.
2. This function is more efficient that using nested maxloc and max functions.
3. Related function amaxlocy will return the Y location of the maximum grid value.
4. Use the amax function to retrieve the maximum value over the grid.
5. If more than one grid box contains the maximum value, the location returned will be the first one encountered as the grid is scanned. The grid is scanned by rows from south to north, and each row is scanned from west to east.
6. A similar set of functions exists for finding the minimum over an area: amin, aminlocx, and aminlocy.

Examples