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Script regarding non numerical or empty value

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# 1  
Old 02-15-2017
Script regarding non numerical or empty value
Hello Team,

I need bash script to check if my output is non numerical or empty. if its then my output should display default value as 0

basically, I am reading value from txt file. most of numerical value, in case there is no numerical value or its empty, then my output should be 0.

example like below:
Code:
output=`sed '1!d' $SOURCE_FOLDER/$datafile |awk '{print $6}'`
          data="lines1=$output "

          output=`sed '1!d' $SOURCE_FOLDER/$datafile |awk '{print $7}'`
          data+="lines2=$output "

          echo "file value|$date"

Br,Pradeep
Last edited by ghpradeep; 02-15-2017 at 07:32 AM.. Reason: Add CODE and ICODE tags.
# 2  
Old 02-15-2017
In lieu of two sed invocations followed by an awk each, you could try a single awk:
Code:
awk '{print "lines1=" ($6==$6+0?$6:0) " lines2=" ($7==$7+0?$7:0); exit}' file3
lines1=41531.0 lines2=52529.0
awk '{print "lines1=" ($6==$6+0?$6:0) " lines2=" ($7==$7+0?$7:0); exit}' logfile
lines1=0 lines2=0

Last edited by RudiC; 02-15-2017 at 06:09 PM.. Reason: typo
This User Gave Thanks to RudiC For This Post:
Chubler_XL
# 3  
Old 02-15-2017
Another approach using awk:

Code:
awk '{printf("lines1=%d lines2=%d\n", $6+0, $7+0); exit }' infile

Originally I was going to use NR==1 to match the first line but RudiC's approach using exit should be much more efficient when the input file has a large number of lines.

Replace %d format specifiers with %f, %.2f, etc if you have non-integer values.
This User Gave Thanks to Chubler_XL For This Post:
RudiC
# 4  
Old 02-15-2017
Nice approach! In fact, with the %d format specifier, you don't need the +0 as both an empty or a string field would result in a 0 to be printed:
Code:
cf file[1-3]
file1:
/ home k abc txt ABC DEF 
file2:
/ home k abc txt 92 1023
file3:
AB CD EF
awk '{printf("lines1=%d lines2=%d\n", $6, $7); exit }' file1
lines1=0 lines2=0
awk '{printf("lines1=%d lines2=%d\n", $6, $7); exit }' file2
lines1=92 lines2=1023
awk '{printf("lines1=%d lines2=%d\n", $6, $7); exit }' file3
lines1=0 lines2=0

The only drawback is when a field has a string starting with numeric characters like
Code:
cat file4
A B C D E F23 24G H

Your approach:
Code:
awk '{printf("lines1=%d lines2=%d\n", $6+0, $7+0); exit }' file4
lines1=0 lines2=24

My approach:
Code:
awk '{print "lines1=" ($6==$6+0?$6:0) " lines2=" ($7==$7+0?$7:0); exit}' file4
lines1=0 lines2=0

The OP needs to decide which one would satisfy his/her needs.
# 5  
Old 02-16-2017
Thanks all for reply, I have quick question here. how about having multiple lines in single file like below.
.
Code:
e.g
100 4  5 101 400
 900 1245 789 P

I want to read multiple lines from files and display output related each field.
my output should be like this.
Code:
process1= 100
process2 = 900
process3 = 789 
process4 = 0

process4 will be 0 since its having non numerical value.

# 6  
Old 02-16-2017
Awk has a built in variable NR which matches the row number of the file so you can test this when extracting your process numbers:

Code:
awk '
NR==1 { printf("process1= %d\n", $1+0) }
NR==2 { 
   printf("process2 = %d\n", $1+0)
   printf("process3 = %d\n", $3+0)
   printf("process4 = %d\n", $4+0)
   exit
}' infile

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