The challenge
Given a string s, write a method (function) that will return true if its a valid single integer or floating number or false if its not.
Valid examples, should return true:
isDigit("3")
isDigit(" 3 ")
isDigit("-3.23")
should return false:
isDigit("3-4")
isDigit(" 3 5")
isDigit("3 5")
isDigit("zero")
Test cases
test.assert_equals(isDigit("s2324"), False)
test.assert_equals(isDigit("-234.4"), True)
The solution in Python
Option 1(with try/except):
# create a function
def isDigit(string):
# use a `try/except` block
try:
# True if can convert to a float
float(string)
return True
except:
# otherwise return False
return False
Option 2(with regex/Regular expression):
# import the regex match module
from re import match
def isDigit(string):
# return a Boolean if the match was met
return bool(match(r"^[-+]?\d+\.?\d*?$", string))
