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I have raster dataset for rainfall but it does not have an attribute table.

How can I create tabular data using the same raster file and the join back again to it?

Software used is ArcMap 10.1.

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You could use the Build Raster Attribute Table (Data management) tool. Note that the raster must have a single band and the pixel values must be integer type (not float or double) to have an attribute table.

  • is there any other way of doing it? – user24101 Nov 21 '13 at 6:14
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    is the aforementioned procedure not working for you? – Rob Lodge Nov 21 '13 at 12:55
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    If your data was for example to 2 decimal places then you can multiply your data by 100 to move the decimal place and then use the INT tool to convert it into an integer grid. Then you'll be able to build raster table as described above.You just got to remember to divide any output by 100 to turn it back into the original values. – Hornbydd Nov 8 '14 at 20:50
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I found this problem occuring mainly when handling raster data with floating point data. The straight forward approach (in the ArcMap Toolbox' sense of way):

  1. ArcToolbox > Spatial Analyst Tools > Map Algebra > Raster Calculator

    Multiply your raster by 10**X with X corresponding the maximum decimal places contained. The new raster should now be free of digits, although still being a floating pixel value raster.

  2. ArcToolbox > Data Management Tools > Raster > Raster Dataset > Copy Raster

    In the Pixel Value drop-down menu select the Pixel Type suiting your data.

  3. Now that you have a non-float raster (and ArcMap surely loves these) create an attribute table:

    ArcToolbox > Data Management Tools > Raster > Raster Properties > Build Raster Attribute Table

  4. Open the attribute table, add a field and use Field Calculator to get your old pixel values back - by calculating "Your Value= 1 / 10**X"

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    One to any power is just one. DId you mean ten to the Nth power? – Vince Dec 2 '17 at 2:00
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You can use Int tool to convert floating point to integer raster and after you process that, the attribute table will appear.

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