Which, not only is ugly and slow

I'd dispute both.

A regex or other string parsing method would be uglier and slower.

I'm not sure that anything much could be faster than the above. It calls the function and returns. Try/except doesn't introduce much overhead because the most common exception is caught without an extensive search of stack frames.

The issue across programming languages is that any numeric conversion function has two kinds of results:

• A number, if the number is valid;
• A status code (e.g., via errno) or exception to show that no valid number could be parsed.

C (as an example) hacks around this a number of ways. Python lays it out clearly and explicitly.

I think your code for doing this is just fine. The only thing that could be cleaner is moving the return True into an else block, to be clear that it's not part of the code under test – not that there's much ambiguity.

def is_number(s):
    try:
        float(s)
    except ValueError:  # Failed
        return False
    else:  # Succeeded
        return True

Here is the method to check,

a = '10'
if a.isdigit():
   print "Yes it is Integer"
elif a.replace('.','',1).isdigit() and a.count('.') < 2:
   print "Its Float"
else:
   print "Its is Neither Integer Nor Float! Something else"

If you're really just annoyed at using try/excepts all over the place, please just write a helper function:

def represents_int(s):
    try: 
        int(s)
    except ValueError:
        return False
    else:
        return True

>>> print(represents_int("+123"))
True
>>> print(represents_int("10.0"))
False

It's going to be WAY more code to exactly cover all the strings that Python considers integers. I say just be pythonic on this one.

Python3 method to check for float:

def is_float(element: any) -> bool:
    #If you expect None to be passed:
    if element is None: 
        return False
    try:
        float(element)
        return True
    except ValueError:
        return False

Python2 version of the above: How do I parse a string to a float or int?

Always do unit testing. What is and is not a float may surprise you:

Command to parse                        Is it a float?  Comment
--------------------------------------  --------------- ------------
print(isfloat(""))                      False
print(isfloat("1234567"))               True 
print(isfloat("1_2_3.4"))               True        123.4, underscores ignored
print(isfloat("NaN"))                   True        nan is also float
print(isfloat("123.456"))               True
print(isfloat("123.E4"))                True
print(isfloat(".1"))                    True
print(isfloat("6.523537535629999e-07")) True
print(isfloat("6e777777"))              True        This is same as Inf
print(isfloat("-iNF"))                  True
print(isfloat("1.797693e+308"))         True
print(isfloat("infinity"))              True
print(isfloat("1,234"))                 False
print(isfloat("NULL"))                  False       case insensitive
print(isfloat("NaNananana BATMAN"))     False
print(isfloat(",1"))                    False           
print(isfloat("123.EE4"))               False           
print(isfloat("infinity and BEYOND"))   False
print(isfloat("12.34.56"))              False       Two dots not allowed.
print(isfloat("#56"))                   False
print(isfloat("56%"))                   False
print(isfloat("0E0"))                   True
print(isfloat("x86E0"))                 False
print(isfloat("86-5"))                  False
print(isfloat("True"))                  False       Boolean is not a float.   
print(isfloat(True))                    True        Boolean is a float
print(isfloat("+1e1^5"))                False
print(isfloat("+1e1"))                  True
print(isfloat("+1e1.3"))                False
print(isfloat("+1.3P1"))                False
print(isfloat("-+1"))                   False
print(isfloat("(1)"))                   False       brackets not interpreted

Sinking exceptions like this is bad, because killing canaries is bad because the float method can fail for reasons other than user input. Do not be using code like this on life critical software. Also python has been changing its contract on what unicode strings can be promoted to float so expect this behavior of this code to change on major version updates.