Aggregation

LazyFrame.count()	Return the number of non-null elements for each column.
LazyFrame.max()	Aggregate the columns in the LazyFrame to their maximum value.
LazyFrame.mean()	Aggregate the columns in the LazyFrame to their mean value.
LazyFrame.median()	Aggregate the columns in the LazyFrame to their median value.
LazyFrame.min()	Aggregate the columns in the LazyFrame to their minimum value.
LazyFrame.null_count()	Aggregate the columns in the LazyFrame as the sum of their null value count.
LazyFrame.quantile(quantile[, interpolation])	Aggregate the columns in the LazyFrame to their quantile value.
LazyFrame.std([ddof])	Aggregate the columns in the LazyFrame to their standard deviation value.
LazyFrame.sum()	Aggregate the columns in the LazyFrame to their sum value.
LazyFrame.var([ddof])	Aggregate the columns in the LazyFrame to their variance value.