Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

JavaScript The Solution

Colin Grubbs
Colin Grubbs
2,137 Points

Does isNaN change the value of the variable to NaN?

When I build the message variable and write the message to the doc when the "not a number" test fails, I notice it changed the input you provide to "NaN" onto the web page. Does this have to do with the parseFloat method?

1 Answer

Hi Colin!

No, isNaN is only a test function, it is not transformative.

More info:

https://www.w3schools.com/jsref/jsref_isnan.asp

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN

I'd have to see your actual code to analyze the situation further...

This might address the parseFloat part of your question, though:

https://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_parsefloat

(See what happens to var g)

I hope that helps.

Stay safe and happy coding!