0

I have a CSV file with the general format shown in the picture below.

In that CSV there are multiple rows that belong to a certain column (desc) and I would like to to extract those items and add them to new columns called name, size, weight, glass, respectively. I have highlighted (in red) those sub-row items for the entries.

Original Structure:

enter image description here

Expected Structure:

enter image description here


The original CSV:

page,item,id,desc,price
1,2,F1,Alpha,111.11
1,,,380 x 2280 mm (size),
1,,,Weight: 33.0 kg,
1,,,Glass: AAA,
1,,,XXX,
1,3,F2,Beta,222.22
1,,,880 x 2280 mm (size),
1,,,Weight: 68.4 kg,
1,,,Glass: BBB,
1,,,YYY,
1,4,F3,Gamma,333.33
1,,,1980 x 1580 mm (size),
1,,,Weight: 78.2 kg,
1,,,Glass: CCC,
1,,,XXX,
1,,,YYY,
1,,,ZZZ,

Expected resulting CSV:

page,item,id,name,size,weight,glass,price
1,2,F1,Alpha,380 x 2280,33.0,AAA,111.11
1,3,F2,Beta,880 x 2280,68.4,BBB,222.22
1,4,F3,Gamma,1980 x 1580,78.2,CCC,333.33

where name would take the place of the first row in desc.


UPDATE:

Under certain conditions, some Awk solutions may work with the above, but fail when adding a 4th item. To fully test, consider adding this to the above:

1,7,F4,Delta,111.11
1,,,11 x 22 mm (size),
1,,,Weight: 33.0 kg,
1,,,Glass: DDD,
1,,,Random-1,

So 3 important points:

  • The number of sub-rows in the desc column may vary.
  • Any sub-rows after Glass:... should be ignored.
  • There may be items that doesn't have any sub-rows in the desc column, they should also be ignored.

Q: How can I remap those sub-rows into new columns, using Awk?
(Or are there more suitable tools for doing this in bash?)

Possibly related (but not very helpful) Questions:

3
  • Can the item value ever be the number 0? – Ed Morton Apr 29 at 13:58
  • Hi @EdMorton, no, but since the actual data is OCR extracted from a PDF file, there certainly could be garbage. I've tried to do some rudimentary pre-filtering using: awk -F'[,"]' '($2~/[0-9]+/ && $3~/F[0-9]+/) || (!$2 && !$3)', because there may be rows that look like: sometimes,shit,happens,with,data. – not2qubit Apr 29 at 16:31
  • -F'[,"]' is pretty suspect. Actually so are the other conditions. If you post a new question we can help you with that filtering. – Ed Morton Apr 29 at 16:38
2
awk 'BEGIN{ FS=OFS=","; print "page,item,id,name,size,weight,glass,price" }
    $2!=""{ price=$5; data=$1 FS $2 FS $3 FS $4; desc=""; c=0; next }
          { gsub(/ ?(mm \(size\)|Weight:|kg|Glass:) ?/, "") }
    ++c<=3{ desc=(desc==""?"":desc OFS) $4; next }
    data  { print data, desc, price; data="" }
' infile

including explanation:

awk 'BEGIN{ FS=OFS=","; print "page,item,id,name,size,weight,glass,price" }
     #this block will be executed only once before reading any line, and does: 
            #set FS (Field Separator), OFS (Output Field Separator) to a comma character
            #print the "header" line  ....

    $2!=""{ price=$5; data=$1 FS $2 FS $3 FS $4; desc=""; c=0; next }
    #this blocks will be executed only when column#2 value was not empty, and does:
            #backup column#5 into "price" variable
            #also backup columns#1~4 into "data" variable
            #reset the "desc" variable and also counter variable "c"
            #then read next line and skip processing the rest of the code 

          { gsub(/ ?(mm \(size\)|Weight:|kg|Glass:) ?/, "") }
            #this block runs for every line and replace strings above with empty string

    ++c<=3{ desc=(desc==""?"":desc OFS) $4; next }
    #this block runs at most 3reps and 
           #joining the descriptions in column#4 of every line
           #and read the next line until counter var "c" has value <=3 

     data { print data, desc, price; data="" }
     #if "data" variable has containing any data, then
           #print the data, desc, price and empty "data" variable 
' infile 
0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.