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Determine if variable is numeric

Determine if variable is numeric


Hi all, on a scale of 1 to 100, 100 being a Python expert, I am a 1.
I inherited a bunch of Python scripts and now I have to change one.

This is the current code. It checks the length of the PropID and if it is 10, then it is a good ID.

CODE --> python

if len(str(self.propid)) == 10:
    self.is_valid_sungard_id = True
    self.is_valid_sungard_id = False 
However the ID needs to start with a numeric for it to be truly valid.

Can anyone help?

CODE --> pseudo

if Left 1 is numeric and the length is 10 then it is a good PropID 

Thanks in advance!

RE: Determine if variable is numeric

1st of all you want to check each condition separately (this will make it easier to maintain & add attitional check of modify existing ones.

the following is some very curde code that may need a little cleaning up


#new method to add to your class
def check_id(self):
valid_first_chars=[str(x) for x in range(10)] id=str(self.propid) # isnt this a string anyway? if len(id)!=0:
return False
if id[0] not in valid_first_chars:
return False
#add additional checks here if req return True
#using the new method self.is_valid_sungard_id=self.check_id(self)

A Maintenance contract is essential, not a Luxury.
Do things on the cheap & it will cost you dear

RE: Determine if variable is numeric


Quote (IPGuru)


if len(id)!=0:
  return False 
Few identifiers will pass so strict validation...

Why not use str.isdigit() ?

CODE --> python

>>> 'bad'[0].isdigit()

>>> '5good'[0].isdigit()


RE: Determine if variable is numeric

if len(id) !=0:

Deliberate typo to check everyone was watching (thats my story & i am sticking to it smile )


I forgot about that, although my solution of checking members of a list does give some scope for amending the valid lead character

Hey I said it was quick & dirty code.

A Maintenance contract is essential, not a Luxury.
Do things on the cheap & it will cost you dear

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