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Re: Constant function Integrate Assumption

• To: mathgroup at smc.vnet.net
• Subject: [mg47212] Re: Constant function Integrate Assumption
• From: bobhanlon at aol.com (Bob Hanlon)
• Date: Wed, 31 Mar 2004 02:57:31 -0500 (EST)
• References: <c4bdnf$6tr$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

With[{Months = 1}, Integrate[UnitStep[t Months], t]]

Integrate[UnitStep[t Months], t, Assumptions -> Months == 1]

Integrate[UnitStep[t Months] /. Months -> 1, t]

Integrate[UnitStep[t Months] /. x_*Months -> x, t]


Bob Hanlon

In article <c4bdnf$6tr$1 at smc.vnet.net>, dsr14 at Cornell.edu (Daryl Reece) wrote:

<< I am trying to use units within an Integration and would like
Mathematica to understand that the units (Month) are not a function of
the integration variable, but I have not had any luck with my
attempts.

Specifically

Integrate[UnitStep[t Months], t]

should yield

t UnitStep[t]

but I get the unevaluated form, because Mathematica does not know how to
assume that Month is not a function of t.

I've tried Assumptions, SetAttribute, Replace...to no avail.  I've
also hunted extensively online (Wolfram, this group and MathGroup)
without any results, so any help would be greatly appreciated.