1

I've been working on this for a day or two in order to tell if an input is an integer, float or string.

In short the program is designed to turn every input into a string, loop through each string and check through the list digits. If the string has all digits its an integer, if it has a '.' its a float, and if it has none it's not a number. The obvious flaw is strings containing letters and '.' which would be considered floats in this program.

The end goal for this program is to open text files and see what input is an int, float, or other.

Questions

-Is there any way to further optimize this program

-How can I further modify this program to open text files, read, analyze, and write which input is in which list

First post!!!

#Checks input to see if input is integer, float, or character

integer = []
float = []
not_number = []

digits = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']
input_list = [100, 234, 'random', 5.23, 55.55, 'random2']

for i in input_list:

    i = str(i) 
    length = len(i)

    count = 0 
    marker = 0

    for j in i:
        for k in digits:
            if k == j:
                count = count + 1

#k loops through digits to see if j single character 
#string input is number

        if count == length:
            integer.append(i)
            marker = 1

#count is equal to length if entire string is integers

        if j == '.':
            float.append(i)
            marker = 1

#Once '.' is found, input is "considered" a float

        if marker == 1:
            break
    else:
        not_number.append(i)

#If code above else proves that input is not a number the 
#only result is that it isn't a number

print ('Integers: ', integer)
print ('Float: ', float)
print ('Not Numbers', not_number)
Alexander
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5 Answers5

4

If you are reading from a text file, you will get always string, so you can decide to which type belong each element using int() and float() and trapping the exception:

integers = []
floats = [] # Don't use float as a variable, it will override a built-in python function
not_number = []

# I modified this list so all the elements are string, if you already have ints and floats, you can use type() to know where to append
input_list = ["100", "234", 'random', "5.23", "55.55", 'random2']

for i in input_list:
    value = None
    try:
        value = int(i)
    except ValueError:
        try:
            value = float(i)
        except ValueError:
            not_number.append(i)
        else:
            floats.append(value)
    else:
        integers.append(value)

print(not_number)
print(floats)
print(integers)

# ['random', 'random2']
# [5.23, 55.55]
# [100, 234]
Ruben Bermudez
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1

You don't have to convert the data to string and process them, you can simply use type function to get the type and put the result in a dict like this.

input_list = [100, 234, 'random', 5.23, 55.55, 'random2']
result = {}
for item in input_list:
    result.setdefault(type(item), []).append(item)
print('Integers: ', result[int])
# Integers:  [100, 234]
print('Float: ', result[float])
# Float:  [5.23, 55.55]
print('Not Numbers', result[str])
# Not Numbers ['random', 'random2']
thefourtheye
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1

You can actually check it in this way

 if type(i) is IntType:
   #do something
 if type(i) is StrType:
   #do something
 if type(i) is FloatType:
   #do something

http://docs.python.org/2/library/types.html

PYPL
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  • Or, as the documentation for that module tells you, you could just use `int`, `str`, and `float` instead of the `types` module: "Starting in Python 2.2, built-in factory functions such as int() and str() are also names for the corresponding types. This is now the preferred way to access the type instead of using the types module." – user2357112 Mar 06 '14 at 03:48
  • Much easier than what I was thinking. – Alexander Mar 06 '14 at 03:52
1

Better solution to those looking for smaller and more optimized code

integer = []
floats = []
not_number = []
full_list = [100, 234, 'random', 5.23, 55.55, 'random2', 'vdfj.324.23tk.sdfklsj']



for i in full_list:
    if isinstance(i, int):
        integer.append(i)
    elif isinstance(i, float):
        floats.append(i)
    else:
        not_number.append(i)
print ('Integers ', integer)
print ('Floats ', floats)
print ('Not numbers ', not_number)
Alexander
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0

you can make use of the eval function of python. for checking whether input string is of what type simply use type(eval( your string )).

ayush1794
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