Function _isnumber

tabulate/__init__.py:903–952

Detects if something *could* be considered a numeric value, vs. just a string. This promotes types convertible to both int and float to be considered a float. Note that, iff *all* values appear to be some form of numeric value such as eg. "1e2", they would be considered numbers! T

(string)

def _isnumber(string):
    """Detects if something *could* be considered a numeric value, vs. just a string.

    This promotes types convertible to both int and float to be considered
    a float.  Note that, iff *all* values appear to be some form of numeric
    value such as eg. "1e2", they would be considered numbers!

    The exception is things that appear to be numbers but overflow to
    +/-inf, eg. "1e23456"; we'll have to exclude them explicitly.

    >>> _isnumber(123)
    True
    >>> _isnumber(123.45)
    True
    >>> _isnumber("123.45")
    True
    >>> _isnumber("123")
    True
    >>> _isnumber("spam")
    False
    >>> _isnumber("123e45")
    True
    >>> _isnumber("123e45678")  # evaluates equal to 'inf', but ... isn't
    False
    >>> _isnumber("inf")
    True
    >>> from fractions import Fraction
    >>> _isnumber(Fraction(1,3))
    True

    """
    return (
        # fast path
        type(string) in (float, int)
        # covers 'NaN', +/- 'inf', and eg. '1e2', as well as any type
        # convertible to int/float.
        or (
            _isconvertible(float, string)
            and (
                # some other type convertible to float
                not isinstance(string, (str, bytes))
                # or, a numeric string eg. "1e1...", "NaN", ..., but isn't
                # just an over/underflow
                or (
                    not (math.isinf(float(string)) or math.isnan(float(string)))
                    or string.lower() in ["inf", "-inf", "nan"]
                )
            )
        )
    )


def _isint(string, inttype=int):