AWK / Linux script calculations from a text file

Question

I wrote an AWK script that read files and multiplies rows by columns and sum them up. I want to pass several files (any number of files) as an argument in awk script at a time eg A.txt, B.txt, C.txt. I want the AWK script to give me sum of rows and columns. I always want to skip first 5 columns from each text file.

Each text file can have any number of columns. There can be several text files inside a folder.

I want to run as:

awk -f foo.awk A.txt B.txt C.txt

eg

If there are 3 different files A.txt, B.txt, C.txt, sum up multiplication of rows and columns from each 3 files.

Output should be:

No of columns in A.txt: count of columns in A.txt with first 5 columns ignored
No of columns in B.txt: count of columns in B.txt with first 5 columns ignored
No of columns in C.txt: count of columns in C.txt with first 5 columns ignored
Sum of A.txt: rows in A.txt*columns in A.txt
Sum of B.txt: rows in B.txt*columns in B.txt
Sum of C.txt: rows in C.txt*columns in C.txt
Total Sum: A+B+C

Below is (sort of pseudo-code) what I have got so far for foo.awk (it is not working with multiple files):

#!/bin/gawk -f

BEGIN { rows=0; columns=0 }
{
    FS="\t";
    if(/^#COLS/) {
            column=NF-5; #skip first 5 columns
            columns+=column
    }
    if (!/^#/){
            rows++;
            files[FILENAME]++;
    }
}
END {
    for (fname in files) {
            printf ("%'24d rows in %s\n",files[fname],fname);
    }
            printf("No of columns in A.txt= %'d\n", columnsA);
            printf("No of columns in B.txt= %'d\n", columnsB);
            printf("No of columns in C.txt= %'d\n", columnsC);
            sum=columns*rows; # multiply no of rows by column in each file and add them up 
            printf( "Sum of A.txt %d\n", sumA);
            printf( "Sum of B.txt %d\n", sumB);
            printf( "Sum of C.txt %d\n", sumC);   
            printf( "Total sum is %d\n", sum_of_A+B+C);  
}

eg

A.txt:
#ignore this line -- pattern does not match
#ignore this line -- pattern does not match
#COLS   A       B       C       D       E       F       G       H       I 
row1    1       2       3       4       5       6       7       8       9
row2    1       3       3       4       5       6       7       8       9
row3    1       3       3       4       5       6       7       8       9

B.txt:
#ignore this line -- pattern does not match
#ignore this line -- pattern does not match
#COLS   A       B       C       D       E       F       G       H        
row1    1       2       3       4       5       6       7       8       
row2    5       3       3       4       6       6       7       8       
row3    8       3       3       4       5       6       7       8       

C.txt:
#ignore this line -- pattern does not match
#ignore this line -- pattern does not match
#COLS   A       B       C       D       E       F       G       H       I       J
row1    1       2       3       3       5       6       7       8       9       2
row2    7       3       3       4       5       6       7       8       9       7
row3    9       3       3       4       5       6       7       8       9       6
row4    9       3       3       4       5       6       7       8       9       6

output:

No of columns in A.txt: 5
No of columns in B.txt: 4
No of columns in C.txt: 6
Sum of A.txt: 3*5=15
Sum of B.txt: 3*4=12
Sum of C.txt: 4*6=24
Total Sum: 12+9+20 = 51

Thank you.

Answer 1

with plain awk you can do this

$ awk '!/^#/{cols[FILENAME]=NF-5; 
             rows[FILENAME]++} 
         END{for(f in cols) print "No of columns in " f, cols[f]; 
             for(f in cols) 
               {r=rows[f];
                c=cols[f];
                sum+=r*c; 
                sumstr=sumstr?sumstr"+"r*c:r*c; 
                print "Sum of "f ":",r "x" c "=" r*c} 
             print "Total Sum: ", sumstr, "=", sum}' {A,B,C}.txt

No of columns in C.txt 6
No of columns in B.txt 4
No of columns in A.txt 5
Sum of C.txt: 4x6=24
Sum of B.txt: 3x4=12
Sum of A.txt: 3x5=15
Total Sum:  24+12+15 = 51

There is a mismatch in number of columns, are you skipping 5 or 6. Also note that the order of entries is not preserved, can be fixed with gawk sorted-in, or with little extra coding as below...

$ awk 'FNR==1{order[++k]=FILENAME} 
        !/^#/{cols[FILENAME]=NF-5; rows[FILENAME]++} 
          END{for(i=1;i<=k;i++) print "No of columns in " order[i], cols[order[i]]; 
              for(i=1;i<=k;i++) {f=order[i];r=rows[f];c=cols[f];sum+=r*c; sumstr=sumstr?sumstr"+"r*c:r*c; print "Sum of "f ":",r "x" c "=" r*c} 
              print "Total Sum: ", sumstr, "=", sum}' {A,B,C}.txt

No of columns in A.txt 5
No of columns in B.txt 4
No of columns in C.txt 6
Sum of A.txt: 3x5=15
Sum of B.txt: 3x4=12
Sum of C.txt: 4x6=24
Total Sum:  15+12+24 = 51