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batch line-by-line bitwise functions (bitwise logic operator equivalent of diff/comm?) – CentOS

I’m researching the rhythmic elements of prime number sequences in binary. I have multiple sets of files containing vertical lists, and I want to apply bitwise logic operators between any two of them line-by-line.

i.e.

$cat binary-superprimes.txt
11
101
1011
10001
11111
101001
111011
1000011
1010011
1101101
$cat binary-perniciousprimes.txt 
11
101
111
1011
1101
10001
10011
11111
100101
101001

I’m looking for commands, a script, or an application (I’d prefer commands/a script but its not deal-breaking) that will let me and/or/xor/etc. these outputs in order line-by-line, in much the same style/similar to the output of diff or comm.

Using CentOS 7/Ubuntu 18.04/MacOS 10.15.

edit
Expected output (binary expansion of XORing each entry above in decimal):

0
0
1100
11010
10010
111000
101000
1011100
1110110
1000100

As for what I’ve tried, as I said I’ve played around with for loops, but I don’t know how (or if its possible) two iterate two lists for comparison in this context (i.e. two “for i in”‘s with a single “done” – using $i and $x as inputs for a basic “echo (($x^$i))”

I’ve also tried a program called “bitwise” but its output is too verbose and it cannot seem to read files, only values.

Tags:

2

Answers


  1. 0

    You can use bc for this purpose. First you create file

    xor.bc

    define xor(x,y) {
 auto n,z,t,a,b,c,os,qx,qy;
 os=scale;scale=0
 n=0;x/=1;y/=1
 if(x<0){x=-1-x;n=!n}
 if(y<0){y=-1-y;n=!n}
 z=0;t=1;while(x||y){
  qx=x/4;qy=y/4;
  c=(a=x-4*qx)+(b=y-4*qy) 
  if(!c%2)c=a+4-b         
  z+=t*(c%4)
  t*=4;x=qx;y=qy
 }
 if(n)z=-1-z
 scale=os;return (z)
}

    Then you create loop to get the numbers one by one. And you can exec XOR by this:

    paste binary-superprimes.txt binary-perniciousprimes.txt |while read var1 var2;
do
    echo "ibase=2;obase=2;xor($var1;$var)|bc -l xor.bc
done
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  2. 0

    Assuming your bash version is >= 4.0 and supports mapfile,
    would you try the following:

    mapfile -t x < "binary-superprimes.txt"
mapfile -t y < "binary-perniciousprimes.txt"

for (( i=0; i<${#x[@]}; i++ )); do
    echo "obase=2;" $(( 2#${x[i]} ^ 2#${y[i]} )) | bc
done

    Output:

    0
0
1100
11010
10010
111000
101000
1011100
1110110
1000100

    In case your bash does not support mapfile command, please try the alternative:

    while read -r line; do
    x+=($line)
done < "binary-superprimes.txt"

while read -r line; do
    y+=($line)
done < "binary-perniciousprimes.txt"

for (( i=0; i<${#x[@]}; i++ )); do
    echo "obase=2;" $(( 2#${x[i]} ^ 2#${y[i]} )) | bc
done

    Hope this helps.

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