how do I get the value of expr with ksh

Thread Tools Search this Thread
Top Forums UNIX for Advanced & Expert Users how do I get the value of expr with ksh
# 1  
Old 08-24-2001
how do I get the value of expr with ksh


I have written a korn shell script to compute the value of k.

formulae :


my shell script is :

k=`expr (($a + $b ) * $c )`
echo $k

### here paranthesis ( ) not accepting by expr function.
### if i remove paranthesis, the value will be 610(wrong)
### but the actual value should be 900

please give me solution to


# 2  
Old 08-24-2001
Hi Krisna,

try it with "let"


let k="($a + $b) * $c"


Smilie greetings
# 3  
Old 08-25-2001
KSH Maths

Why using 'expr' if you can use the built-in KSH math functions instead:

k=$ ((($a+$b)*$c )))
echo $k

# 4  
Old 08-26-2001
using expr

"expr" evaluates 2 and only 2 expressions.
In order to accomplish what you want to do
using "expr" you need to nest expr's and
of course, remember to "escape" the speecial
characters. An example would be...

echo `expr \`expr 1 + 2\` \* 3`

This expression, when run at the command
prompt, should yield 9. Of course, if you
are using ksh and not planning on running
a different shell, I would stick with the
ksh built-in capabilities.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Nn$( expr $n + 1)

HI there I am trying to understand Shell scripting to create my own, I am attempting a few examples can anyone tell me what this means?n=$( expr $n + 1)Tried looking on the internet, but just cannot find its anywhere :( .Help please (4 Replies)
Discussion started by: steve2015
4 Replies

2. Shell Programming and Scripting

If + expr

Hi I have bellow script: t1=`cat node1.txt | grep thread1 | cut -f2 -d '-'` t2=`cat node2.txt | grep thread2 | cut -f2 -d '-'` t3=`cat node1_rcat.txt | grep thread1 | cut -f2 -d '-'` t4=`cat node2_rcat.txt | grep thread2 | cut -f2 -d '-'` if ]; then echo "no restore" >> log.log... (6 Replies)
Discussion started by: primo102
6 Replies

3. Shell Programming and Scripting

Error with expr - "expr: syntax error"

Hi All, I'm writing a shell script in KSH, where I want to store the filename, total record count and actual record count of all the source files. The source files reside in 4 different sub-folders under the same root folder. Below is code: #!/usr/bin/ksh... (6 Replies)
Discussion started by: jagari
6 Replies

4. UNIX for Dummies Questions & Answers

expr ?!

Hey there i want to subtract the content from $b from $a. Each variable has got 18 values (normal numbers from 0 - 99). How can i subtract them? I know i have to use the expr command, this is what i have till now: a=`cat Tabelle.dat | awk {'print $4'} | awk -F: {'print $1'}` b=`cat... (1 Reply)
Discussion started by: Mad van Bert
1 Replies

5. Shell Programming and Scripting

the expr \*

$ cat > mtable #!/bin/sh # #Script to test for loop # # if then echo "Error - Number missing form command line argument" echo "Syntax : $0 number" echo "Use to print multiplication table for given number" exit 1 fi n=$1 for i in 1 2 3 4 5 6 7 8 9 10 do echo "$n * $i = `expr $i \*... (1 Reply)
Discussion started by: jackel7777
1 Replies

6. Shell Programming and Scripting

test expr VS [ expr ]

What is the difference between test expr VS . For example : if test 5 -eq 6 echo "Wrong" and if echo "Wrong" bot will give the same output as Wrong. Now, what is the difference between these two? though they are producing the same result why we need two? Any answer will be... (2 Replies)
Discussion started by: ashok.g
2 Replies

7. Red Hat

how to use expr

i am new to shell programming, currently using redhat linux of version 2.4.20-8. i have problem in executing expr command in the following shell script $ x=5 $ x='expr $x + 1' $ echo $x the output is displaying always expr $x + 1 Pls guide me for the above query (3 Replies)
Discussion started by: saikumarm80
3 Replies

8. Shell Programming and Scripting

expr inside a ksh script Solaris

Hi; If I do something like this. dftotalsize=0;export dftotalsize;df -k | grep \/db001 | awk '{print $4}' | while read theinput \ ; do export $theinput; dftotalsize=`expr $dftotalsize + $theinput`; export dftotalsize; echo $dftotalsize; done ; echo `expr $dftotalsize \/ 1024 \/ 1024 "GB" Is... (4 Replies)
Discussion started by: myjess
4 Replies

9. Shell Programming and Scripting

expr error in ksh

Hi ALL, i am so much confused y the following script is not working in the korn shel which works in bash shell. please solve the error that i am facing. i want to extract the format of the size from a variable i.e. GB or KB or MB or B or BYTES code: -------- size_dir_pass=1.2gb... (2 Replies)
Discussion started by: G.K.K
2 Replies

10. Shell Programming and Scripting

ksh script using expr to calculate percentages

Within a ksh script on HP-UX I trying to calculate a percentage of a number (number/100 x percentage) using the below method and expr. TARPERC=`expr 16 / 100 \* 5` TARSUM=`expr 16 + $TARPERC` ZIPSUM=`expr $TARSUM \* 2` If the input is 16 outputs are: TARPERC: 0 TARSUM: 16 ZIPSUM: 32... (6 Replies)
Discussion started by: wurzul
6 Replies
Login or Register to Ask a Question