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Re: How to deal with big matrix?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg116649] Re: How to deal with big matrix?
  • From: Mala Jozsef <mala_jozsef at freemail.hu>
  • Date: Tue, 22 Feb 2011 06:25:23 -0500 (EST)

You can try this if your matrix is m:
  Map[#[[1]]&,m,{2}] Jozsef   
Szymon Roziewski <szymon.roziewski at gmail.com> =EDrta:
>Hello there,
>
>I have quite big matrix with let say 1000 rows and 1100 columns.
>Each of element of this matrix is a point on a surface e.g. {1.232,12.123}
>How can I quickly get first element of each point for whole matrix and put
>it in a vector (1000*1100 - this will be a length of that vector) without do
>it in a nested loop (Do[Do[...]])?
>And the similar to get the second element of each point into vector.
>
>kind regards,
>Szymon Roziewski
Out[22]= {{1,3,5},{a,c,e}}Out[22]= {{1,3,5},{a,c,e}}Out[28]= A very large output was generated. Here is a sample of it:
{0.235,{{0.308717,0.434524,0.580005,0.133084,0.577401,0.116256,0.809947,0.950517,0.186649,0.706007,0.588812,<<1079>>,0.995572,0.37737,0.0956442,0.802109,0.482953,0.397557,0.213774,0.936062,0.161284,0.968476},<<998>>,{<<1>>}}}
Show Less\[ThinSpace]Show More\[ThinSpace]Show Full Output\[ThinSpace]Set Size Limit...



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