EliminatePwl canonicalizer for the cumulative max atom

EliminatePwl.cummax_canon(expr, args)

## Arguments

expr

An Expression object

args

A list of Constraint objects

## Value

A canonicalization of the piecewise-lienar atom constructed from a cumulative max atom where the objective function consists of the variable Y which is of the same dimension as the original expression and the constraints consist of row/column constraints depending on the axis