New to Java

I have used a Scanner Object before to read doubles from an input, but how do I get the Next double from a String?

Used this in the past:

Scanner input = new Scanner(System.in);
double num = input.nextDouble();

I am looking for something like this:

String example = "100.00Degrees";
double num = example.nextDouble();
// num now equals 100.00

Any suggestions?