Shell Programming and Scripting

BEGIN {
  if (cols=="") cols=12
}
{
  for(i=1; i<=NF;i++) {
    col = ((col++)%cols)+1
    if (col==1) row++
    arr[row,col]=$i
  }
}
END {
  for(i=row; i;i--)
    for(j=1; j<=cols; j++)
      printf("%s%c", arr[i,j], !(j%cols)?ORS:OFS)
}

#!/usr/bin/python
length_of_a_row=1977
input_file='infile.dat'
output_file='outfile.dat'
data=open(input_file).read() # opens the file and reads it into memory
data=data.split() #turns it into one long list of single numbers
data2=[] #we'll need this as an empty list in the for-loop
for i in xrange(len(data)/length_of_a_row):
 data2.append(data[length_of_a_row*i:length_of_a_row*(i+1)])
#reshapes it in the size of the matrix
data=[] # free a bit of memory
data2.reverse() #resort with first row at bottom
#get rid of the array shape:
data=" ".join([" ".join(x) for x in data2]) # turn it into one long string
data2=[]
data=data.split() # and split it into one long list again 
#get it into output shape again:
for i in xrange(len(data)/6):
 data2.append(data[6*i:6*(i+1)])
data2.append(data[6*(len(data)/6):len(data)]) #the last line is not full length
data=[] #free some memory
#write the whole stuff out to hard disk
out=open(output_file,'w') 
out.write("\n".join([" ".join(x) for x in data2]))
out.write('\n')
out.close()

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BEGIN {
  if (cols=="") cols=12
}
{
  for(i=1; i<=NF;i++) {
    col = ((col++)%cols)+1
    if (col==1) row++
    arr[row,col]=$i
  }
}
END {
  for(i=row; i;i--)
    for(j=1; j<=cols; j++)
      printf("%s%c", arr[i,j], !(j%cols)?ORS:OFS)
}

nawk -v cols=15 -f mat.awk mat.txt

61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15