Re: List manipulation
- To: mathgroup at smc.vnet.net
- Subject: [mg70214] Re: List manipulation
- From: "Ray Koopman" <koopman at sfu.ca>
- Date: Sat, 7 Oct 2006 07:08:45 -0400 (EDT)
- References: <eg4rtn$fah$1@smc.vnet.net>
xun wrote:
> Hello,
>
> I have something as following:
>
> a = Array[aa, {3, 3}];
> b = Array[bb, {3, 3}];
> c = Array[cc, {3, 3}];
> d = Array[dd, {3, 3}];
> A = {{a, b}, {c, d}} (* A consists of four blocks *)
> A // MatrixForm
>
> And I want a 6*6 matrix (a list of 6 lists) just as A looks like.
> For example, the first row should be
>
> aa[1,1],aa[1,2],aa[1,3],bb[1,1],bb[1,2],bb[1,3]
>
> etc....
>
> How to get it easily?
>
> Many thanks.
> Xun
In[7]:= MapThread[Join,{Join[a,c],Join[b,d]}]
Out[7]= {{aa[1,1],aa[1,2],aa[1,3],bb[1,1],bb[1,2],bb[1,3]},
{aa[2,1],aa[2,2],aa[2,3],bb[2,1],bb[2,2],bb[2,3]},
{aa[3,1],aa[3,2],aa[3,3],bb[3,1],bb[3,2],bb[3,3]},
{cc[1,1],cc[1,2],cc[1,3],dd[1,1],dd[1,2],dd[1,3]},
{cc[2,1],cc[2,2],cc[2,3],dd[2,1],dd[2,2],dd[2,3]},
{cc[3,1],cc[3,2],cc[3,3],dd[3,1],dd[3,2],dd[3,3]}}