Use Perl In Bash Script To Compare Floationg Points


 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Use Perl In Bash Script To Compare Floationg Points
# 1  
Old 10-07-2009
Use Perl In Bash Script To Compare Floationg Points

Is there a way to compare two floating points numbers in a bash script using perl? I've tried just using a bash if statement and it doesn't seem to support floating point numbers. Can the perl line read vars from bash then output a var to bash?

Code:
a=1.1     #from bash
b=1.5     #from bash
if b > a  #perl
then X=1  #perl    X to bash

# 2  
Old 10-07-2009
no need for perl.
Code:
#!/bin/ksh

a=1.72
b=1.71

if [ "$(echo "if (${a} > ${b}) 1" | bc)" -eq 1 ] ; then
   echo ">"
else
   echo "<"
fi;

# 3  
Old 10-07-2009
Does it work in just sh? Or is there a way to make just that portion of the script run in ksh if that is needed?
# 4  
Old 10-07-2009
Quote:
Originally Posted by Grizzly
Does it work in just sh? Or is there a way to make just that portion of the script run in ksh if that is needed?
Code:
#!/bin/sh

a=1.72
b=1.71

if [ "`echo "if (${a} > ${b}) 1" | bc`" -eq 1 ] ; then
   echo ">"
else
   echo "<"
fi;

Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Compare date bash script

I all I have written a bash script for compare two date. One of those is a result of query, and another is current date. I have a problem with the format, because the first is 09/12/19 18:50:30 but for having this result I have to do d1DB=$(date -d "$valData" +'%m/%d/%y %T') and the second... (9 Replies)
Discussion started by: rdie77
9 Replies

2. UNIX for Beginners Questions & Answers

Bash script to compare file all the files exits or not

Currently i am building a script like based on region parameter it will filter the records in config file and then it will create a text file like ab.txt and it will read the path location in that file and now i need to compare the files name in the config file to files in the path of the config... (1 Reply)
Discussion started by: saranath
1 Replies

3. Shell Programming and Scripting

Array compare bash script

Hello, i have a script that should compare between ${ARRAY} that contains all fstab record like this : >>echo ${ARRAY} / /boot between all mountpoints in my df that is stord in ${ARRAY2} >>echo ${ARRAY2} / /boot /dev/shm /var/spool/asterisk/monitor now i have this loop: for i in... (6 Replies)
Discussion started by: batchenr
6 Replies

4. Shell Programming and Scripting

Bash script to compare 2 file

Hello Friends please help me to create script to compare 2 fiile which has rpm info . File 1: glibc-2.12.1.149.el6_6.5.x86_64.rpm glibc-common-2.12-1.149.el6_6.5.x86_64.rpm File 2 : glibc-2.12.123.el6_6.5.x86_64.rpm glibc-common-2.12-123.el6_6.5.x86_64.rpm To compare file1... (1 Reply)
Discussion started by: rnary
1 Replies

5. Shell Programming and Scripting

Compare & Copy Directories : Bash Script Help

Beginner/Intermediate shell; comfortable in the command line. I have been looking for a solution to a backup problem. I need to compare Directory 1 to Directory 2 and copy all modified or new files/directories from Directory 1 to Directory 3. I need the directory and file structure to be... (4 Replies)
Discussion started by: Rod
4 Replies

6. Shell Programming and Scripting

Bash script to compare two lists

Hi, I do little bash scripting so sorry for my ignorance. How do I compare if the two variable not match and if they do not match run a command. I was thinking a for loop but then I need another for loop for the 2nd list and I do not think that would work as in the real world there could... (2 Replies)
Discussion started by: GermanJulian
2 Replies

7. Shell Programming and Scripting

How to compare time in bash script?

Hi, Anyone know how to compare the time in bash script? I want to compare say 30 min. to 45 min. ( AIX ) Thanks. (1 Reply)
Discussion started by: sumit30
1 Replies

8. Red Hat

Points to compare Linux distros

I 've a question regarding which points should be considered to compare 2 different linux distros say RedHat & Ubuntu. for a production environment non-db applications ... any help will be appreciated .. (1 Reply)
Discussion started by: fugitive
1 Replies

9. Shell Programming and Scripting

count and compare no of records in bash shell script.

consider this as a csv file. H,0002,0002,20100218,17.25,P,barani D,1,2,3,4,5,6,7,8,9,10,11 D,1,2,3,4,5,6,7,8,9,10,11 D,1,2,3,4,5,6,7,8,9,10,11 D,1,2,3,4,5,6,7,8,9,10,11 D,1,2,3,4,5,6,7,8,9,10,11 T,5 N i want to read the csv file and count the number of rows that start with D and... (11 Replies)
Discussion started by: barani75
11 Replies

10. Shell Programming and Scripting

passing variable from bash to perl from bash script

Hi All, I need to pass a variable to perl script from bash script, where in perl i am using if condition. Here is the cmd what i am using in perl FROM_DATE="06/05/2008" TO_DATE="07/05/2008" "perl -ne ' print if ( $_ >="$FROM_DATE" && $_ <= "$TO_DATE" ) ' filename" filename has... (10 Replies)
Discussion started by: arsidh
10 Replies
Login or Register to Ask a Question

Featured Tech Videos