[GRASS-user] 10day accumulation which t.rast module to use?

[maning sambale]

Dear Vero,

Thanks for the reply.  But t.rast.aggregate does not do what I intend
to do.  My rainrate is from a span of 20 days.
t.rast.aggregate produces (as expected) two rasters, one for each of
the 10day accumulation.  What I want for example is like a moving sum,
where for each day, it calculates the sum for the past 10 days.

On Thu, Dec 4, 2014 at 4:31 AM, Veronica Andreo <veroandreo at gmail.com> wrote:
> Hi Emmanuel,
>
>> Hi,
>>
>> I have 3hourly rainrate data for a given region in a GRASS temporal
>> database (strds).
>>
>> I want to aggregate the data by summing all raster from the previous
>> 10 days to calculate the accumulated rainfall.
>> The temporal modules have several tools:
>> t.rast.series
>> t.rast.accumulate
>> t.rast.aggregate
>> t.rast.mapcalc
>>
>> >From the manual, the appropriate module seems to be t.rast.accumulate
>> but it does not have sum in the method parameters. Currently, I'm
>> running several r.series commands for each day like below:
>>
>> r.series input=\
>> "`t.rast.list input=3hr_rainrate where=\
>> "('${DATE} 00:00:00' >= datetime(start_time, '3 hours')) \
>> and ('${DATE} 00:00:00' <= datetime(start_time, '10 days')) " \
>> col=name method=comma`" \
>> output="test_2014-07-20" method=sum
>>
>> Then, register each layer in another strds:
>>
>> #Create a new STRDS
>> t.create output='10day_accumulation' type='strds' temporaltype='absolute'
>> \
>>             title='10day_accumulation' \
>>             description="10 day rainfall accumulation"
>>
>>
>> g.mlist type='rast', pattern='test*', separator=','
>>
>> #Register the r.series output to the strds
>> t.register -i type=rast input=10day_accumulation \
>>         start="2014-07-10 00:00:00" increment="1 days" separator="," \
>>         maps="`g.mlist type='rast', pattern='test*', separator=','`"
>>
>>
>> Is there another approach using directly any of the t.rast.* modules.
>> For a time-line visualization, here's what I want to do:
>> https://dl.dropboxusercontent.com/u/2096185/sample_accumulation.png
>>
>> Thanks!
>
> If i understood right, something like
>
> t.rast.aggregate input=3hr_rainrate output=10day_rain basename=10day_rain
> granularity='10 days' method=sum
>
> should do the what you need.
>
> HTH,
>
> Vero



-- 
cheers,
maning
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