FloatToStrF
Converts a floating point value to a string, using a specified Format, Precision, and Digits
For a general description see, e.g., http://www.delphibasics.co.uk/RTL.asp?Name=floattostrf.
Generally, a good formatting control can be achieved using ffFixed (=2):
floatToStrF(123456.789012, 2, 7, 2)
will display up to 7 digits before and 2 digits after the decimal separator (for this example this will yield 123456,80).