1

I have time series raster data in PostGIS and I can't find a way to get the info as a time series from an XY point.

For example:

I would like to get the vale of the XY point in raster for the 13/08/2015 - 20/08/2015

I have one raster for each day in the year 2015, each raster has values of some data from remote sensing satellite and I want to see how the value is changing week on week.

Example

and so on.

  • what you want to do with the value? Calculate the mean for a week or something? Not entrirely sure if i understand it correctly. – Matte Aug 13 '16 at 12:22
2

When you want to summarize a value for a given time slot you can use the date_trunc function to group your data. For example:

select 
date_trunc('week', your_date_column),
min (X),
min (Y),
mean(value)
from your_table
group by date_trunc('week', your_date_column)

The min (X) is needed for the aggregation as otherwise the program does not know how to handle the 7 values. As they are identical you can acutally use any aggregate function here.

  • hi thank you for the answer, is thare a way to get the vale for each day in the week so i can plot a time series(no Calculate for the vale just get the vale for for each day of the week) – YARON Aug 13 '16 at 15:18

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