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PORead variables from two files and output in a pattern on 3rd file
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  1. PORead variables from two files and output in a pattern on 3rd file
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    copied!<p>I have 2 files like below:</p> <p>file1:</p> <pre><code>a1,b1,c1,d1,e1,f1,g1,h1 a2,b2,c2,d2,e2,f2,g2,h2 a3,b3,c3,d3,e3,f3,g3,h3 a4,b4,c4,d4,e4,f4,g4,h4 </code></pre> <p>file2:</p> <pre><code>x1,y1,z1 x2,y2,z2 x3,y3,z3 x4,y4,z4 </code></pre> <p>I want to read simultaneously from both and output the variables in a pattern like below:</p> <pre><code>a1,b1,c1,d1,x1,e1,f1,y1,g1,z1,h1 a2,b2,c2,d2,x2,e2,f2,y2,g2,z2,h2 a3,b3,c3,d3,x3,e3,f3,y3,g3,z3,h3 a4,b4,c4,d4,x4,e4,f4,y4,g4,z4,h4 </code></pre> <p>Good news - I've managed to achieve it !!</p> <p>Bad news - Too many arrays and while loops (too much computation!). I am looking for something simpler as the script will have to read through much data (4k lines and 1M words).</p> <p>Limitation - BASH shell (probably not a limitation!)</p> <p>This is what I've done</p> <pre><code>exec 5&lt;file1 # Open file into FD 5 exec 6&lt;file2 # Open file into FD 6 while IFS=$"," read -r line1 &lt;&amp;5 IFS=$"," read -r line2 &lt;&amp;6 do array1=( `echo $line1` ) array2=( `echo $line2` ) array3=("${array1[@]}","${array2[@]}") echo ${array3[@]} &gt;&gt; tmpline done while IFS="," read var1 var2 var3 var4 var5 var6 var7 var8 var9 var10 var11 do echo -e "$var1,$var2,$var3,$var4,$var9,$var5,$var6,$var10,$var8,$var11,$var9" &gt;&gt; tcomb done &lt; tmpline exec 5&lt;&amp;- # Close FD 5 exec 6&lt;&amp;- # Close FD 6 </code></pre> <p>Thanks in advance -- I'm waiting patiently :) !!</p>
 

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