Converting Vdop string to float

Recently I got help and managed to extract the Vdop parameter using the TinyGPS++ library.
I would like to convert it to numerical, float, in order to perform a range check before sending the value to an I2C LCD.
Compiler errors tells me that the Vdop is delivered as a character string so a "tmp_float = Float(Vdop)" does not compile.

Reading Arduino reference manual I don't find any suitable conversion function.
Chewing down the string byte by byte, creating a numerical, is of course doable but not worth the effort.
Anybody having sharper eays or more knowledge the I have?

Anybody having sharper eays or more knowledge the I have?

atof()

Hi and thanks a lot again!
atof().. Ascii to Float..... How could I miss that?
Being burned out, leving the programming profession 10 years ago have made 30 years of experience start to corrodeā€¦.