Trouble using .is_integer() in python

Question

I am trying to develop a python script that loops through a set of subdirectories I have and extracts a data file from each of those subdirectories. My subdirectories are each named for their corresponding time in a simulation I have fun earlier. However, the issue is that the integer subdirectories are listed without a decimal point (e.g. 5), while the non-integer subdirectories are listed with a decimal point. So in order to find the correct subdirectory, my loop is very sensitive to the number type.

With that, I have been trying to use the is._integer() method with python, but I keep getting this error:

'int' object has no attribute 'is_integer'

when I run the following code:

def frange(x, y, jump):
    while x < y:
        yield x
        x += jump

time=15

for i in frange(0,time,0.1):
    float(i)    
    print (i).is_integer() 

even when I am brute forcing my loop variable to be a float! Please help.

Answer 1

Try print(float(i).is_integer())

The reason is that despite the fact that you casted i with float(i) before the usage of (i).is_integer(), it did not mutate the variable type of i to float.

Answer 2

float(i)

This converts the argument i into a float, but that result is returned; it does not modify the variable i. So what that call does is simply discarded.

And in your case, in the first iteration, i is 0 which is an actual integer, and integer objects don’t have an is_integer method. So you either want to assign the restult of float(i) back to i:

for i in frange(0, time, 0.1):
    i = float(i)
    print (i).is_integer()

… or make sure that frange only returns floats:

def frange(x, y, jump):
    x = float(x)
    while x < y:
        yield x
        x += jump

Answer 3

You do not assign cast value to a variable. This should work:

def frange(x, y, jump):
    while x < y:
        yield x
        x += jump

time=15

for i in frange(0,time,0.1):
    x = float(i)    
    print (x).is_integer()