我想在 python 中的一个变量上使用 2 种数据类型？

Question

Im trying to get float data type available on my code. My code so far is;

age = int (input("Age of the dog: "))

if age <= 0:
    print ("This can not be true!")
elif age == 1:
    print ("He/she is about 14 in human years.")
elif age == 2:
    print ("He/she is about 22 in human years.")
elif age > 2:
    human = 22 + (age - 2) * 5
    print ("He/she is about", human, "human years")

Answer 1

Since you didn't mention whether you want the age given is float or the output should be in float, I added both here :-)

For only "getting" floating point, your code will suffice. Except that the floating point number would be rounded off. If you do not want the number to be rounded, instead of int(input( , use float(input( and you are good to go.

In case you want to process the age as floating point, you can just change the age calculation logic a little to ensure more readability that you are processing age as float. Also adding exception handling won't hurt either.

The code with exception handling as well:

try:
    age = float(input("Age of the dog: "))
except:
    print "Age given is not a valid number"
    age = 0

if age <= 0:
    print ("This can not be true!")
elif age == 1:
    human_age = 14
elif age == 2:
    human_age = 22
elif age > 2:
    human_age = 22.0 + ((age - 2) * 5.0)
print ("He/she is about %f human years" % (human_age))

Answer 2

If you change your first line to

age = float(input("Age of the dog: "))

your program will show a floating point age.