I pushed eight free AI chatbots to their limits to find the best AI chatbots of 2026. To explore our top picks, check out ZDNET's chatbot-by-chatbot guide.

Dr. James McCaffrey presents a complete end-to-end demonstration of linear regression with pseudo-inverse training implemented using JavaScript. Compared to other training techniques, such as ...

You’ve used SUM for years. It adds numbers, does its job, and you probably don’t think twice about it. But while you’ve been clicking through filters and building messy helper columns, Excel has been ...

I'm a software developer and writer, passionate about learning and sharing knowledge and one way I do that is through writing. I'm a software developer and writer, passionate about learning and ...

Have you ever thought of the humble SUM function as a secret weapon for advanced analytics? Most Excel users see it as a basic tool for adding numbers, but what if I told you it could do so much more?

Have you ever struggled with Excel formulas, trying to calculate running totals only to be left with errors and frustration? Many of us have faced the challenge of managing datasets where each row’s ...

You can use the Sum function in Microsoft Office Excel to sum columns of data, whether your data is in an Excel table or is simply a range in a column of your worksheet. The sum of a column of zeros ...

When you create an array in PHP, you'll want to be able to use it. To do so, you have to manipulate or loop through it. PHP provides several built-in functions for manipulating arrays and several ways ...

To sum and subtract in Google Sheets, use the formula =SUM(x:y) or =MINUS(x,y) in the desired cells and input the relevant values. Press Enter to get the results. Adding up columns or rows of numbers ...