Check for length which exceeds specified length in a line

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# 1  
Old 11-21-2012
Check for length which exceeds specified length in a line


I have a issue, I need to loop through a comma delimited file and check for the length which exceeds specified length , if Yes truncate the string.
But my problem is , I do not have to check for all the fields and the field lenght is not same for all the fields.

For ex:

Say my line

say I need to check length only for 2nd and 4th and max length for 2nd is 6 and max length for 4th field is 4.

Can somebody please help me.
I was trying with AWK , but couldn't move forward with it , please let me know if my logic is correct.

awk 'BEGIN{ FS = OFS = ","
 for (i=1;i<=len,i++) {
  for (j in len) {
  if (length($(field[i])) = len[j] )

# 2  
Old 11-21-2012
Is this what you are trying to do?
awk -F, ' { if(length($2)>6) $2=substr($2,1,6); if(length($4)>4) $4=substr($4,1,4); print; } ' OFS=, filename

# 3  
Old 11-21-2012
awk -F, 'BEGIN {len="5,6,7,8";split(len,arr,",");}{for(i=1;i<=NF;i++){if(length($i)>arr[i])next}}1' input.csv

$ cat input.csv

$awk -F, 'BEGIN {len="5,6,7,8";split(len,arr,",");}{for(i=1;i<=NF;i++){if(length($i)>arr[i])next}}1' input.csv

5,6,7,8 is the length to check the 1,2,3,4 fileds

if you want to check only for some particular fields, then

$awk -F, 'BEGIN {len="5,0,0,8";split(len,arr,",");}{for(i=1;i<=NF;i++){if( arr[i]!=0 && length($i)>arr[i])next}}1'  input.csv

# 4  
Old 11-21-2012
If you are checking only for few specific columns then use.

$ cat file

$ awk -F, 'length($2) <= 6 && length($4) <= 4' file

# 5  
Old 11-25-2012
Thank you guys , checking the length and print works , but I also need to print the field name along with it . But somehow I am not able to print the field.
Can you please tell if we can print the array value.

For exp in the above example

This is what I tried
  nawk -F, 'BEGIN {len="5,6,7,8";split(len,arr,",");col="col1,col2,col3,col4";split(col,arr1,",");}{for(i=1;i<=NF;i++){if(length($i)>arr[i]) $i=substr($i,1,arr[i]); print${arr1[i]} next}}1' input.txt

 checking,the, lengthof, string

check,the, lengtho, string,Field col1,col3 exceeds the length

# 6  
Old 11-25-2012
Try this; may need some polishing, esp. reg. the lenghts to be supplied in a variable:
$ cat file
checking,the, lengthof, string
$ awk -F, 'BEGIN {split("5,6,7,8", len, ",");  OFS=","}
           {for (i=1; i<=NF; i++) if(length($i) > len[i]) {$i = substr($i, 1, len[i]); col[i]++; OA=1}}
           {printf "%s", $0;
            if (OA) {printf ", Fields ";
                     for (i=1; i<=NF; i++) {if (col[i]) printf "col%d ", i; col[i]=0;}
                     printf "exceed the length."
            printf "\n"; OA=0
          ' file
 check,the, length, string, Fields col1 col3 exceed the length.

Last edited by RudiC; 11-25-2012 at 07:16 PM..
# 7  
Old 11-26-2012
Thank you , this is how I want the result to be , but my column names are not exactly col1, col2 etc . Actually they are different.


name, city, zipcode, state, country,eff_date, start_date, end_date.

I need to display the actual field name for ex: city, zipcode, start_date is null.

I am not able to read this in an array. can you please help me .
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