Re: How to Extract Conditional Expression?
- To: mathgroup at smc.vnet.net
- Subject: [mg127589] Re: How to Extract Conditional Expression?
- From: Bob Hanlon <hanlonr357 at gmail.com>
- Date: Sun, 5 Aug 2012 14:58:34 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- Delivered-to: l-mathgroup@wolfram.com
- Delivered-to: mathgroup-newout@smc.vnet.net
- Delivered-to: mathgroup-newsend@smc.vnet.net
- References: <20120805063431.92A6F6766@smc.vnet.net>
expr = x -> ConditionalExpression[#1^2 + 3 #1 + 2 C[1], C[1] in Integers];
f[x_] = expr[[-1, 1]] /. {Slot[1] -> x, C[1] -> 3}
6 + 3 x + x^2
However, I suspect that the condition is actually Element[C[1], Integers]
expr = x ->
ConditionalExpression[#1^2 + 3 #1 + 2 C[1], Element[C[1], Integers]];
f[x_] = Assuming[expr[[-1, -1]], Simplify[expr[[-1]]]] /. {Slot[1] -> x,
C[1] -> 3}
6 + x (3 + x)
And if the original expr also actually included a pure function
expr = x ->
ConditionalExpression[#1^2 + 3 #1 + 2 C[1] &, Element[C[1], Integers]];
f[x_] = Assuming[expr[[-1, -1]], Simplify[expr[[-1]] /. C[1] -> 3]][x]
6 + 3 x + x^2
Depending on how your original expression was generated, you might be
able to remove the condition earlier with an option such as
GenerateConditions -> False
Bob Hanlon
On Sun, Aug 5, 2012 at 2:34 AM, ScottG <sbg at acw.com> wrote:
> I have ...
>
> x -> ConditionalExpression[#1^2 + 3 #1 + 2 C[1], C[1] in Integers]
>
> and I want
>
> f[x_] = x^2 + 3 x + 6
>
> How do I get there other than cut-and-paste?
>
> Thanks for any insight.
>
> Cheers, Scott
>
>
>
- References:
- How to Extract Conditional Expression?
- From: ScottG <sbg@acw.com>
- How to Extract Conditional Expression?