Hi
I have some twenty years of weather data with daily average temperature. I would like to make a histogram with aggregated monthly average for the whole period. I tried to do something like this Trends and Seasonalities: New in Wolfram Language 11
But it didnt work since my weights in WeightedData can be both positive and negative. My data looks like this:
Any help would be much appreciated
Can you explain why you need to weight the data to compute monthly averages? Why can’t you use TimeSeriesAggregate?
My goal is to make a histogram of the average seasonal variation so i need the January in that diagram to be the average for all Januaries over the period. The same for Feb, Mar and so on.
First i used TimeSerieAggregate to make a monthly series. Then i tried (as you can see in the last part of my link) to make a DateHistogram. Then i realized that i cant use the same method as the link because my weights (being temperature) could be both negative and positive, so I need another way of doing a histogram with the total average temperature for each month during the whole period.
Hi Nils,
I think I understand what you are trying to do, but I still don’t understand why weighting by temperature is needed. Does something like this satisfy your requirements?
Since your profile says you are in Sweden, get the daily mean temperature in Stockholm for 2008 to 2018
byDay = WeatherData["Stockholm", "MeanTemperature", {{2008, 1, 1}, {2018, 12, 31}, "Day"}]
Average over months (could have specified “Month” in WeatherData, but you have data by day)
byMonth = TimeSeriesAggregate[byDay, "Month", Mean]
Plot looks reasonable
DateListPlot[byMonth]
Group the data by month name
groupByMonth = GroupBy[byMonth["DatePath"], DateValue[First[#], "MonthNameShort"] &]
Compute average by month
meanByMonth = Mean[Map[Last, #]] & /@ groupByMonth
Plot BarChart
BarChart[meanByMonth, ChartLabels -> Automatic]
You could also compute min, max and mean
minMaxMean = {Min[Map[Last, #]], Max[Map[Last, #]], Mean[Map[Last, #]]} & /@ groupByMonth
and visualize as a BoxWhiskerChart
BoxWhiskerChart[minMaxMean, ChartLabels -> Automatic, PlotTheme -> "Detailed"]
Great! thats a really good answer, thanks alot
