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I downloaded a raster image of the sea floor age. The values in band 1 ranges from -32768 to 32767. I need to reclassify it to no. of million of years to make sense of the data. How can I do so? I try to use Raster Calculator but I do not know how to input the syntax. Any kind soul able to help? Thanks.

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up vote 1 down vote accepted

I guess your data is from In the data description linked at the bottom of the site it is stated that the raster values are millions of years, mutlipied by 100. So you have to divide by 100.

In Raster calculator, double-click on the @1, click on the / and input 100 afterwards. select new filename, and add data to the canvas. The new extend is max 278.35 instead of 27835 from the original layer.

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