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Re: How to remove external parentheses from a list

• To: mathgroup at smc.vnet.net
• Subject: [mg131523] Re: How to remove external parentheses from a list
• From: Murray Eisenberg <murray at math.umass.edu>
• Date: Sat, 17 Aug 2013 02:07:23 -0400 (EDT)
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One way is to use Sequence with Apply (@@). For example:

   Integrate[x1 + x2^2, Sequence @@ {{x1, a, b}, {x2, c, d}}]

On Aug 16, 2013, at 7:06 AM, Samuel Mark Young <sy81 at sussex.ac.uk> wrote:

>
> Hello,
>
> I'm looking for an easy way to remove the external parentheses from a list.  The list contains integration variables and their respective limits, it currently looks something like this:
>
> {{x1,a,b},{x2,c,d},...,{xn,y,z}}
>
> However, the Integrate (or NIntegrate function) in Mathematica wants me to write it like this:
>
> {x1,a,b},{x2,c,d},...,{xn,y,z}
> i.e. The external parentheses have been removed
>
> I've looked around online and seen suggestions for replacing the curly brackets "{" with a blank space " ", or using Apply (@@) but can't work out the correct syntax.
>
> Thanks for any help and advice!
>
> Regards,
> Sam
>

---
Murray Eisenberg                                    
murray at math.umass.edu
Mathematics & Statistics Dept.      
Lederle Graduate Research Tower           
University of Massachusetts 
710 North Pleasant Street  
Amherst, MA 01003-9305

• References:
  • How to remove external parentheses from a list
    • From: Samuel Mark Young <sy81@sussex.ac.uk>