Dear all I have a temporal database of daily gridded rainfall for the last 40 years.
I want to find: 1. Number of times (count) the rainfall was 0 for 'atleast' *continuous *10 days in each year, in 5 years etc. 2. Max number of continuous (> 10days) dry days (rainfall=0) per year, per 5 years etc. In this I want to exclude continuous dry spells less than 10 days. I am trying to use the `t.rast.algebra` following the example given here <https://grasswiki.osgeo.org/wiki/Temporal_data_processing#How_to_count_consecutive_days_that_meet_a_certain_condition.3F> . # Create weekly mask to which we will add 1 or 0 according to temperature in the days within it (each map in this week mask will have a value of 7) t.rast.aggregate input=temperature_daily output=weekly_mask basename=mask_week granularity="1 weeks" method=count # Calculate consecutive days with negative temperatures t.rast.algebra base=neg_temp_days expression="consecutive_days = weekly_mask {+,contains,l} if(temperature_daily < 0 && temperature_daily[-1] < 0 || temperature_daily[1] < 0 && temperature_daily < 0, 1, 0)" The example works, but the above code counts every consecutive day in a week even if there is a break in between. I also didn't understand why the consecutive days are added to the total number of days (+7) in the week in 'mask_week' strds. I tried modifying the aggregate expression, but could not make it work to my requirement as stated above. Could anyone give a hint on how to go about this. Many thanks in advance, Best Regards Sajid
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