Converting array to column matrix

How can we convert the below array (50*50) into a column array which only has the first column (50*1)

Answer 1

[Arif Hoq]

use colon(:). each variable will be forced to be a column vector

col_vector=Eflevel(:)

if you want extract first 50 data(50*1), then

output=col_vector(1:50,1)

[Amy Topaz]

Yeah tried that but it is getting converted into 2500*1. I need just the first column (50*1)

[Arif Hoq]

do you want first 50 rows ? please attach your data. or try

output2=Eflevel(1:50,1)

[Amy Topaz]

Thank you