nctoolkit.DataSet.tvar

DataSet.tvar(over='time', align='right')

tvar: Calculate the temporal variance of all variables Useful for: monthly variance, annual/yearly variance, seasonal variance, daily variance, daily climatology, monthly climatology, seasonal climatology

Parameters:

• over (str or list) – Time periods to average over. Options are ‘year’, ‘month’, ‘day’. This operates in a similar way to the groupby method in pandas or the tidyverse in R, with over acting as the grouping.

• align (str) – This determines whether the output time is at the left, centre or right hand side of the time window. Options are “left”, “centre” and “right”

Examples

If you want to calculate variance over all time steps. Do the following:

>>> ds.tvar()

If you want to calculate the variance for each year in a dataset, do this:

>>> ds.tvar("year")

If you want to calculate the variance for each month in a dataset, do this:

>>> ds.tvar("month")

If you want to calculate the variance for each month in each year in a dataset, do this:

>>> ds.tvar(["year", "month"])

This method will also let you easily calculate climatologies. So, if you wanted to calculate a monthly climatological var, you would do this:

>>> ds.tvar( "month")

A daily climatological variance would be the following:

>>> ds.tvar( "day")