Hi Lem,
You suggested an array because pandapowerbox said in the 1st message in this thread:

Code:

I am thinking maybe using an Array is the best way to go about this, but I am really stumped on how to do this

My question and suggestion were directed to pandapowerbox, not to you. Your script was an excellent example of how to use an array to solve a problem like this; if an array is needed. I'm sorry for the confusion.

Pandapowerbox,
I see a lot of newbie programmers who pay too much attention to the semantics of a possible solution without stepping back to look at the bigger picture. If you start out thinking that you need to add a list of variables and print the sum, then you think about accumulating an array and adding them at the end. But, if your goal is just to get the sum of a list of values, you make the problem much more complex by assuming you need to save the input values as separate variables or as separate members of an array instead of just keeping a running sum as you read each individual value.

I also note that the last line of your starting script:

Code:

echo "($x1 + $x2 | bc))"

almost certainly doesn't do what you wanted it to do.

By passing the quoted string to echo, it expands $x1 and $x2, but doesn't invoke bc. And, if you had left off the double quotes, you also have mismatched parentheses. And, if you had used: echo ($x1 + $x2 | bc) or echo (($x1 + $x2 | bc)) you would have had ksh syntax errors. You could have used echo $($x1 + $x2 | bc) and gotten the result you were probably expecting, but if you're learning ksh, you should look at arithmetic expansion that does all of the work in the shell without needing to invoke another utility (bc in this case). Using arithmetic expansion this would simply be: echo $((x1 + x2)).

You have probably already noticed that the suggestions that Lem and I provided both use ksh's arithmetic expansions sum=$(( $sum + ${array[$i]} )) and sum=$((sum + x)), respectively, rather than invoking awk, bc, dc, expr, perl, or some other utility to perform these simple calculations.

Hopefully, the comments Lem and I have made will help you see that there are almost always several ways to do something in shell scripts and help you think about a few of the possibilities as you tackle new problems like this.