4.4 fpformat -- Floating point conversions
Keywords: lib

# 4.4 `fpformat` -- Floating point conversions

The `fpformat` module defines functions for dealing with floating point numbers representations in 100% pure Python. Note: This module is unneeded: everything here could be done via the `%` string interpolation operator.

The `fpformat` module defines the following functions and an exception:

`fix` (x, digs)
  Format x as `[-]ddd.ddd` with digs digits after the point and at least one digit before. If `digs <= 0`, the decimal point is suppressed.

  x can be either a number or a string that looks like one. digs is an integer.

  Return value is a string.

`sci` (x, digs)
  Format x as `[-]d.dddE[+-]ddd` with digs digits after the point and exactly one digit before. If `digs <= 0`, one digit is kept and the point is suppressed.

  x can be either a real number, or a string that looks like one. digs is an integer.

  Return value is a string.

`NotANumber`
  Exception raised when a string passed to `fix()` or `sci()` as the x parameter does not look like a number. This is a subclass of `ValueError` when the standard exceptions are strings. The exception value is the improperly formatted string that caused the exception to be raised.

Example:

      >>> import fpformat
      >>> fpformat.fix(1.23, 1)
      '1.2'