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This section discusses the conversion specifications for floating-point
numbers: the ``%f`', ``%e`', ``%E`', ``%g`', and ``%G`'
conversions.

The ``%f`' conversion prints its argument in fixed-point notation,
producing output of the form
[`-`

]`ddd``.`

`ddd`,
where the number of digits following the decimal point is controlled
by the precision you specify.

The ``%e`' conversion prints its argument in exponential notation,
producing output of the form
[`-`

]`d``.`

`ddd``e`

[`+`

|`-`

]`dd`.
Again, the number of digits following the decimal point is controlled by
the precision. The exponent always contains at least two digits. The
``%E`' conversion is similar but the exponent is marked with the letter
``E`' instead of ``e`'.

The ``%g`' and ``%G`' conversions print the argument in the style
of ``%e`' or ``%E`' (respectively) if the exponent would be less
than -4 or greater than or equal to the precision; otherwise they use the
``%f`' style. Trailing zeros are removed from the fractional portion
of the result and a decimal-point character appears only if it is
followed by a digit.

The following flags can be used to modify the behavior:

- `
`-`' - Left-justify the result in the field. Normally the result is
right-justified.
- `
`+`' - Always include a plus or minus sign in the result.
- `
- If the result doesn't start with a plus or minus sign, prefix it with a
space instead. Since the `
`+`' flag ensures that the result includes a sign, this flag is ignored if you supply both of them. - `
`#`' - Specifies that the result should always include a decimal point, even
if no digits follow it. For the `
`%g`' and ``%G`' conversions, this also forces trailing zeros after the decimal point to be left in place where they would otherwise be removed. - `
`0`' - Pad the field with zeros instead of spaces; the zeros are placed
after any sign. This flag is ignored if the `
`-`' flag is also specified.

The precision specifies how many digits follow the decimal-point
character for the ``%f`', ``%e`', and ``%E`' conversions. For
these conversions, the default precision is `6`

. If the precision
is explicitly `0`

, this suppresses the decimal point character
entirely. For the ``%g`' and ``%G`' conversions, the precision
specifies how many significant digits to print. Significant digits are
the first digit before the decimal point, and all the digits after it.
If the precision is `0`

or not specified for ``%g`' or
``%G`', it is treated like a value of `1`

. If the value being
printed cannot be expressed precisely in the specified number of digits,
the value is rounded to the nearest number that fits.