overExpr

private fn

Series overExpr(DataFrame df,  Expr inner,  string[]  keys,
       string label)

@trusted

Evaluates an expression per partition and scatters back to input rows (the bare-expression over implementation). Each partition's rows form a sub-frame; the expression evaluates on it; the first row's value of each partition's result scatters to that partition's rows (FLOAT64 output - the compatibility form).

Parameters

`df`	the frame
`inner`	the wrapped expression
`keys`	the partition keys
`label`	the output name

Returns

the scattered FLOAT64 Series.