[Qgis-user] raster: calculate area

[Sebastian Gutwein]

I would use Raster Layer Unique Value Report.
https://docs.qgis.org/3.4/en/docs/user_manual/processing_algs/qgis/rasteranalysis.html#raster-layer-unique-values-report



On Fri, Jan 29, 2021 at 4:08 AM Micha Silver <tsvibar at gmail.com> wrote:

> Hi
>
> On Fri, Jan 29, 2021 at 12:32 AM Azzurra Lentini <azzurralentini at gmail.com>
> wrote:
>
>> Hi List,
>> I have a raster file DTM (altitude attribute in the pixels). I
>> reclassified this raster in 4 classes of altitude and I need to calculate
>> for each class  the area (in how many square meters is each different class
>> extended).
>> I can for example transform the raster file reclassified into a vector
>> file and calculate the area, but is it possible to do without any
>> vectorialization and so directly calculating it from the raster file?
>>
>>
> I you're willing to try using GRASS GIS, then the module r.stats is what
> you want
> https://grass.osgeo.org/grass78/manuals/r.stats.html
>
>>  Thanks, Azzurra
>>
>> --
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>> Consultant Environmental Risk Prevention and Hydrogeology
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>> Italy Mobile Tel.: **(39) 338 24 40 676
>> ++++++++++++++++++++++++++
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>> ++++++++++++++++++++++++++
>>
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>>
>> *azzurra.lentini at uniroma3.it <azzurra.lentini at uniroma3.it> *
>> ++++++++++++++++++++++++++
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>>
>>
>>
>>
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>
>
> --
> Micha Silver
> Ben Gurion Univ
> Sde-Boker Remote Sensing Lab
> cell: +972 (52) 3665918
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Sent from a phone. Amazing! But possibly garbled. Sebastian Gutwein
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