Re: matrix problem
- To: mathgroup at smc.vnet.net
- Subject: [mg107107] Re: matrix problem
- From: dh <dh at metrohm.com>
- Date: Wed, 3 Feb 2010 06:08:21 -0500 (EST)
- References: <hk93ca$f68$1@smc.vnet.net>
Hi,
you want all rows of m1 that have the same starting number as some row
of m2. We may translate this directly into Mathematica code:
m1 = {{1, 2}, {3, 4}, {5, 6}, {7, 8}};
m2 = {{1, 8}, {5, 0}, {9, 7}};
Select[m1, MemberQ[m2[[All, 1]], #[[1]]] &]
Daniel
Piotr Munik wrote:
> Dear Math Group,
>
> I have matrix M and matrix N
> for example
> M={{1,2},{3,4},{5,6},{7,8}}
> N={{1,8},{5,0},{9,7}}
> (dimension is diffrent)
> I need to make new matrixes which include only this rows from matrix M and
> matrix N for which firsts elements are the same in both matrix (M and N).
> so I need
> M1={{1,2},{5,6}}
> N1={{1,8},{5,0}}
> Elements of matrix are real (not always integer)
> Please for help
> Peter
>
>