Here is how to check if a string is a float in Python.

def is_float(string):
    try:
        float(string)
        return True
    except ValueError:
        return False

print(is_float('1.23'))
print(is_float('123'))
print(is_float('1.23a')) 

Copy & Run

True

True

False

---

To check if a string is a number (float) in python, you can use isnumeric() in combination with the replace() method to check if the string can be casted to float or not.

Another way to check if a string can be casted to float is using the str.replace() function in combination with str.isnumeric():

def is_float(string):
    if string.replace(".", "").isnumeric():
        return True
    else:
        return False

print(is_float('1.23')) # True
print(is_float('123')) # True
print(is_float('1.23a')) # False

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