There are a lot of questions on rounding that i have looked at, but they all involve rounding a number to its nearest whole number, or to a certain number of digits. What i want to do is simply convert a string to a double without any added digits on the right of the decimal point. Here is my code and result as of now:

Convert the string 0.78240 to a double, which should be 0.78240 but instead is 0.78239999999999998 when I look at it in the debugger.

The string value is a QString and is converted to a double simply using the toDouble() function.

I don't understand how or where these extra numbers are coming from, but any help on converting from QString to double directly would be greatly appreciated!