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Hello, The calculations are done differently. @SUM is the simple sum of the values over the direction given and the region you request, bug @DIN will take into account the units and grid-cell sizes of the coordinate axes. The descriptions of @SUM and @DIN transformations may be found in the documentation - here is the index. Each description includes a link to a very useful discussion of General Information about transformations. In particular, All integrations and averaging are accomplished by multiplying the width of each grid box or portion of the box by the value of the variable in that grid box—then summing and dividing as appropriate for the particular transformation.For example, yes? use levitus_climatology yes? list/z=0:100/x=180/y=0 temp VARIABLE : TEMPERATURE (DEG C) FILENAME : levitus_climatology.cdf FILEPATH : /home/users/tmap/ferret/linux/fer_dsets/data/ SUBSET : 7 points (DEPTH (m)) LONGITUDE: 179.5E LATITUDE : 0.5S 179.5E 160 0 / 1: 28.12 10 / 2: 28.06 20 / 3: 28.00 30 / 4: 27.92 50 / 5: 27.83 75 / 6: 27.65 100 / 7: 27.24 ! This is the simple sum of the above numbers. yes? list/x=180/y=0 temp[z=0:100@sum] VARIABLE : TEMPERATURE (DEG C) FILENAME : levitus_climatology.cdf FILEPATH : /home/users/tmap/ferret/linux/fer_dsets/data/ LONGITUDE: 179.5E LATITUDE : 0.5S DEPTH (m): 0 to 100 (summed) 194.8 ! This is the weighted integral yes? list/x=180/y=0 temp[z=0:100@din] VARIABLE : TEMPERATURE (DEG C) FILENAME : levitus_climatology.cdf FILEPATH : /home/users/tmap/ferret/linux/fer_dsets/data/ LONGITUDE: 179.5E LATITUDE : 0.5S DEPTH (m): 0 to 100 (integrated) 2778. On 9/19/2017 3:09 AM, Atul Srivastava
wrote:
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