@viraptor: Thanks for checking! You pointed me in the direction of the solution, which is the one nicolai mentions. I printed out the values with printf instead of qDebug() and I figured that printed it out with commas instead of dots.

@nicolai: Thanks a bunch for pointing that out My locale uses commas as decimal points, so that's exactly why it couldn't read the file. I'm using
to set the locale to dots now.

Is this a good way to do this?