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Full Discussion: Problem with Maths
Top Forums Shell Programming and Scripting Problem with Maths Post 302070210 by Quesa on Monday 3rd of April 2006 06:30:31 AM
Old 04-03-2006
Problem with Maths

Heres a script i wrote as a bit of practise. What it does is insert a line in the middle of a file. The line being $1 and the file being $2


#!/bin/bash

rm tempfile
touch tempfile

count=1
linenum= `wc -l < $2`
if [ "$linenum" -eq 0 ]
then
echo $1 >> $2
else

even=`expr "$linenum" % 2`
if [ "$even" -eq 0 ]
then
midline=`expr "$linenum" / 2`
else
midline=`expr "$linenum" / 2`
midline=`expr "$midline" + 0.5`
fi

while [ "$linenum" -gt 0 ]
do
sed -n '$count p' $2 >> tempfile

if [ "$linenum" -eq "$midline" ]
then
echo $1 >> tempfile
fi

count=`expr "$count" + 1`
linenum=`expr "$linenum" - 1`
done
fi
cat tempfile > $2


However when I run this I get the following errors:

testscript: 0: command not found
testscript: [: : integer expression expected
expr: non-numeric argument
testscript: [: : integer expression expected
expr: non-numeric argument
expr: non-numeric argument
testscript: [: : integer expression expected

This would suggest that the expr argument does not have numbers in it. I know I have the variables in double quotes but this should not matter should it. Can anyone help me with any of these errors.
 
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HW_GETOBJECT(3) 							 1							   HW_GETOBJECT(3)

hw_GetObject - Object record

SYNOPSIS
mixed hw_getobject (int $connection, mixed $objectID, [string $query]) DESCRIPTION
Gets an object record. If the second parameter is an array of integer the function will PARAMETERS
o $connection - The connection identifier. o $objectID - The object identifier, or an array of identifiers. o $query - The query string has the following syntax: <expr> ::= "(" <expr> ")" | "!" &lt;expr> | /* NOT */ <expr> "||" <expr> | /* OR */ <expr> "&amp;&amp;" <expr> | /* AND */ <attribute> <operator> <value> <attribute> ::= /* any attribute name (Title, Author, DocumentType ...) */ <operator> ::= "=" | /* equal */ "<" | /* less than (string compare) */ ">" | /* greater than (string compare) */ "~" /* regular expression matching */ RETURN VALUES
Returns the object record for the given object ID if the second parameter is an integer. If the second parameter is an array of integer the function will return an array of object records. In such a case the last parameter is also evaluated which is a query string. SEE ALSO
hw_getandlock(3), hw_getobjectbyquery(3). PHP Documentation Group HW_GETOBJECT(3)

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