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# 1  
Old 06-10-2005
delete line
okay, in my script, I want to do a check on the index field of my table, if the index = A then I want to delete that line (my table only wants numeric indexes) in the file (the rest of the lines are being loaded into a table) does anyone know how I would go about removing one line?
# 2  
Old 06-10-2005
How about this ?

Code:
sed -e '/[A-Z]/d' input.txt >output.txt

removes the line where A occurs.

You could use awk to print the index field for each line and then pipe them to the above sed. If it finds any upper case char, delete the line and output the rest into output.txt

vino
# 3  
Old 06-10-2005
can I output it to a file of the same name as the input, as in, overwrite the old file with the new one minus alphabetic indexes?
# 4  
Old 06-10-2005
or just use awk by itself ...

assuming that the index is field 1 and the table is delimited by [space|tab] ...

Code:
awk '$1 != A' input.txt > output.txt

# 5  
Old 06-10-2005
wait a minute, how does the command know which field to look in for the alphabetic character? The other columns are alphanumeric, what distinguishes on which gets deleted?
# 6  
Old 06-10-2005
sorry, just saw the reply about "field 1", it is actually field 4 so will $4 tell it to look in the 4th field for the chars?
# 7  
Old 06-10-2005
yes ........
 
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