Finishing Projects

For projects 8 and 9, we need to get input for 6 employees and return a formatted list for a payroll sheet.

                In pseudo code (not actual code), this goes something like:
            Create a temp file containing the headings (number, name, rate, hours, etc)
                (echo "Number Name Rate...etc" > temp)
            Create a total variable to store overall total pay for all employees
            While loop for 6 passes
                read number name rate hours overtime
                regularpay=rate*hours
                overtimepay=rate*overtime
                totalweeklypay=regularpay+overtimepay
                total=total+totalweeklypay
                store variables as a new line in temp file
                    (number name rate hours overtime regularpay overtimepay totalweeklypay >> temp)
            done with while loop
            echo “Weekly Payroll”
            use awk to format each line from the temp file                                awk '{printf "%-6s%-13s%-10s%5s%8s%10s%9s%8s%8s\n", $1, $2, $3,"$"$4, $5, "$"$6, "$"$7, "$"$8, “$”9}'        (you may need to edit the %numbers)
            echo “Total: \$$total”

Also, to make this work for reading from a file for project A, try adding “< $1” after the “done” in the while loop.  This takes the first parameter passed at the command line and uses it as the file entry for the read command.

That gets you through project B, actually, since the AWK command is all that’s needed to complete it.  As for “discount”, that’s a new script, and can be found entirely in the student manual, under page 34 or 35 I believe.

Good luck, acolytes!

Ways with Arrays

A collection of variables can be stored within one variable using an array.  It's fairly straghtforward; simply call like a variable like normal, but add a number after it with [] brackets, like this: variable[1]

This one's going to be a hefty example, so bear with me.

#!/bin/bash
#
#Array Demo
#By Jason Groce
#Created 12/5/2011
#
#An Array is a variable that contains multiple values.
#Each value is numbered after the name of the array,
#such as array[4], which may be used as a standard
#variable with special notation, such as $(array[12])
#

echo "This is a demo of how an Array functions."
echo -ne "You may pass a file name to populate the array "
echo "or enter variables manually."
echo -ne "(The file should contain names and numbers,"
echo "one of each per line.)"
echo

typeset -a names
typeset -a numbers
typeset -i num=0

if [ ! -f $1 ]||[ ! $# -eq 1 ]    #if no filename entered
then
        echo -ne "You did not enter a valid file name; "
        echo "begin manual entry."

        echo "Please enter 10 Names, one per line: "
        num=0
        while [ $num -lt 10 ]  #10 times, save name to record
        do
                read names[$num]
                num=$num+1
        done

        echo "Please enter 10 Numbers, one per line: "
        num=0
        while [ $num -lt 10 ]  #10 times, save number to record
        do
                read numbers[$num]
                num=$num+1
        done
else            #if a valid file name entered as parameter
        echo "You entered file $1"

        num=0
        echo "Populating arrays..."
        while read name number  #record name/number for each line
        do
                names[$num]=$name
                numbers[$num]=$number
                num=$num+1
        done < $1
fi

num=$num-1
typeset -i record=0
while [ ! $record -eq 99 ]
do
        echo -ne "Enter a number 0 to $num to display a record "
             "or '99' to quit: "
        read record
        case $record in
                99) echo "Quit"
                     exit
                     ;;
                *)  typeset -i recordNum=$record
                    echo -ne "Record $record "
                    echo -ne "${names[$recordNum]} "
                    echo "${numbers[$record]}"
        esac
done


This script can be coupled with a file containing names and numbers/values, such as this:

Paul pbille
Jason f52560
Richard f49150
Jonathan f51970

To try this out, creating the script as "arrays.sh" and the file as "arraydata.dat", run the command like this:

./arrays.sh arradata.dat

To summarize this, you create an array with typeset -a variable, add data to each array value like this, variable[5]="data", and access that data like this, ${variable[5]}.

Questions? Enjoy, weenix's!