Re: Mystifying Scoping of Piecewise Variable?

*To*: mathgroup at smc.vnet.net*Subject*: [mg116135] Re: Mystifying Scoping of Piecewise Variable?*From*: CHARLES GILLINGHAM <cgillingham1 at me.com>*Date*: Thu, 3 Feb 2011 05:29:24 -0500 (EST)

You want: myFunc = Function[{x}, Piecewise[{{x^2, x < 0}, {x, x >= 0}}]]; Begin forwarded message: From: Frank Iannarilli <frankeye at cox.net> Date: February 02, 2011 3:08:08 AM To: mathgroup at smc.vnet.net Subject: [mg116135] [mg116102] Mystifying Scoping of Piecewise Variable? Perhaps I'm tired, but this is weird: Clear[myFunc] myFunc[y_] = Piecewise[{{x^2, x < 0}, {x, x >= 0}}] (Same behavior below for either Set(=) or SetDelayed(:=) ) Plot[myFunc[y], {y, -10, 10}] (returns empty plot) Plot[myFunc[x], {x, -10, 10}] (returns "expected" piecewise function plot) What is the scoping of the Piecewise variable, in this case "x"? How can one write a Module that creates and returns a Piecewise function? The scope of its argument is unclear to me. Thanks