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awk Question: How to remove lines in which $3 == $1 +4

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Top Forums Shell Programming and Scripting awk Question: How to remove lines in which $3 == $1 +4
# 8  
Old 02-11-2014
Quote:
Originally Posted by Don Cragun
You were very close. Try:
Code:
awk '$3 == ($1 + 4) {print}' input > output

or, more simply:
Code:
awk '$3 == ($1 + 4)' input > output

@Don Cragun
That shouldnt matter as the precedence of '+' is higher than '==' so addition will be performed before the test for equality...
@OP
Post an actual sample of the input file in case the 1st or 3rd columns are strings instead of numbers...
# 9  
Old 02-11-2014
Quote:
Originally Posted by shamrock
@Don Cragun
That shouldnt matter as the precedence of '+' is higher than '==' so addition will be performed before the test for equality...
@OP
Post an actual sample of the input file in case the 1st or 3rd columns are strings instead of numbers...
Hi shamrock,

Yes, I mentioned in message #4 in this thread that the parentheses shouldn't matter. (However, I have seen evidence that some implementations of awk don't conform to the precedence rules specified by the standards.)

And, in message #6, I asked for a sample of the input, and, in message #7, livbaddeley said a sample will be provided tomorrow.
# 10  
Old 02-12-2014
Thank you very much, the code you helped me with works fine!
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