def sum_squares(expr):
"""The sum of the squares of the entries.
Parameters
----------
expr: Expression
The expression to take the sum of squares of.
Returns
-------
Expression
An expression representing the sum of squares.
"""
return square(norm(expr, "fro"))
def huber(x, M=1):
"""The Huber function
Huber(x, M) = 2M|x|-M^2 for |x| >= |M|
|x|^2 for |x| <= |M|
M defaults to 1.
Parameters
----------
x : Expression
A CVXPY expression.
M : int/float
"""
# TODO require that M is positive?
return square(M)*huber_pos(abs(x)/abs(M))
def huber(x, M=1):
"""The Huber function
Huber(x, M) = 2M|x|-M^2 for |x| >= |M|
|x|^2 for |x| <= |M|
M defaults to 1.
Parameters
----------
x : Expression
A CVXPY expression.
M : int/float
"""
# TODO require that M is positive?
return square(M) * huber_pos(abs(x) / abs(M))
