Put a number from a header into a variable?

I have a text file containing the value of a time step (in the header), which I want to assign to a variable. How can I extract this number (just the time step), since the header also contains words? I have provided the header below:

Lead Number 1 Time Step .001 Data Points 6001

Answer 1

[Azzi Abdelmalek]

s='Lead Number 1 Time Step .001 Data Points 6001  '
ts=str2double(regexpi(s,'Step\s*(\d?\.?\d+)','tokens','once'))