4
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I have large number of columns of data. How to put in single matrix?

For example, with test data of 1 x 3 matrixs

test[1] = {1, 1, 1}
test[2] = {2, 2, 2}
test[3] = {3, 3, 3}
test[4] = {4, 4, 4}

I use

Array[test, 4, 1, Join]

and get 1 x 12 matrix

{1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4}

I want to get 4 x 3 matrix

{{1, 2, 3, 4}, {1, 2, 3, 4}, {1, 2, 3, 4}}
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  • 1
    $\begingroup$ Don't you already have a 4 x 3 matrix or let's say 2-dimensional array? $\endgroup$ – Hitesh Gaur Jan 23 at 19:11
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You can try creating an Array and then Transposing:

In[14]:= Transpose @ Array[test, 4]

Out[14]= {{1, 2, 3, 4}, {1, 2, 3, 4}, {1, 2, 3, 4}}
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6
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num = 4;
test[#] & /@ Range[num] // Transpose

{{1, 2, 3, 4}, {1, 2, 3, 4}, {1, 2, 3, 4}}

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  • 4
    $\begingroup$ test /@ Range... will do too. $\endgroup$ – Kuba Jan 23 at 11:38
5
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Array[test, 4, 1, Transpose[{##}] &]

{{1, 2, 3, 4}, {1, 2, 3, 4}, {1, 2, 3, 4}}

also

Array[test, 4, 1, Flatten[{##}, {2}] &]
Array[test, 4, 1, Thread[{##}] &]
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3
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Another possibility:

Array[List /@ test[#] &, 4, 1, Join[##, 2] &]
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0
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I hope this helps in creating the array you're asking about.

Var matrix = new int [4, 3];   
     //this creates an array (of arrays) with 4 rows, 3 columns in each row

IF THE VALUES ARE KNOWN (AS IN YOUR CASE) = 
Var matrix = new int [4, 3];
{
    {1, 1, 1}
    {2, 2, 2}
    {3, 3, 3}
    {4, 4, 4}
}
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