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Find first digit in string using expr index
I have looked for hours for an answer, so I have decided to request your guidance.
I want to substract the first number (series of digits) contained in a string. This string is the output of another command. The substring (number) can be located at any position inside the string.
I want to use only the bash string manipulation facilities, as to avoid using other commands (sed, awk, etc.).
However, it does not state whether "substring" can be a regular expression or not. After trying things like
I reached to the conclusion that substring cannot be a regular expression. Please confirm if this is correct. I know, I learn slow.
Now I found out that this can be solved with a command like
but this is what I wanted to avoid in the first place
So I want to confirm with you guys if there is a way in which I could accomplish this without using external commands.
Thanks a lot, and I hope this post will eventually help others.
Last edited by jcd; 09-05-2008 at 03:27 PM..
Reason: Adding a link to the String Manipulation section of the Advanced Bash-Scripting Guide
What I had in mind yesterday, but didn't have time to finish, was something along the following lines.
It's probably too cumbersome to be of much practical utility, but it does work without any external command (as long as there is a single numeric substring).
Here's another rather monstrous idea (you can do it without Perl, although I would hate to have to):
If i'm given a string like "abc-def-1.2.3", how would I return "1"? I'm new to scripting and got stumped on this problem. Thanks in advance! (7 Replies)
Hi,
I need to use the output of previous command in the next command while using pipe.
Like I am reading a file then I am fetching first line from a file and then I want to know the location of character 'e' in that line.
cat filename|sed -n 1p|expr index ------ e
In above example I... (5 Replies)
Hi every body!
I wrote script on Fedora (bash shell) to check whether a tring enter from user console is start with a uppercase/lowercase letter or a digit. But with this script i have some problem when I enter from character from 'b' to 'z' --> result is uppercase. This code look like ok but i... (9 Replies)
Hi,
I have a string like the following:
/db1/data/GLIDER/SYSTEM.dbf
need to find the postion where "SYSTEM.dbf" starts, so I tried:
LOCATION=/db1/data/GLIDER/SYSTEM.dbf
$ expr index $LOCATION SYSTEM
expr: syntax error
$ expr index "$LOCATION" SYSTEM
expr: syntax error
... (5 Replies)
Hi Masters,
here is my req
I have to create a 12 digit string which includes the user i/p
Like if user input 2334 then the string will be 233411111111 ,if the user inputs 23345 then the string will be 233451111111 ,
So we dont know how many digits will the user inputs output will be 12... (16 Replies)
I have to write a c program which takes a 3 digit number n and calculates the value of (2^n)+1 and then determines the number is prime or not.
I have tried to first calculate the value of 2^n and then adding one to it and then apply the logic of prime number.
but the ultimate problem is that... (7 Replies)
I have a line "My name is Deepak"
How can i search a string Deepak in the line and find out its index position.
Here in this case the result should be 12. (3 Replies)
I need to find the index of last '|' (highlighted in bold) in awk :
|ifOraDatabase.Lastservererr<>0then|iferr_flag<>0then|end if
Please suggest a way... Thanks (5 Replies)
I found below script to check whether the variable is a digit in ksh.
############################
#!/bin/ksh
REPLY="3f"
if ]*\)'` != ${REPLY} && "${REPLY}" != "0" ]]
then
print "is digit\n"
else
print "not digit\n"
fi
############################
Although it works fine, but... (6 Replies)