Python input() function not functioning properly: doesn't seem to record any input. Maybe it's a Linux issue?

Question

I'm seeming to have an issue with running this code that I made:

def acidhenderson():
    ka = input("Enter a Ka value:  ")
    pka = math.log(float(scientific_string(ka)), 10) * -1
    base = float(scientific_string(input("Enter base concentration:  ")))
    acid = float(scientific_string(input("Enter acid concentration:  ")))
    ph = pka + math.log((base / acid), 10)
    print("pH = " + str('%.2f' % ph) + ".")
    print("")
    main()

def main():
    print("1: Calculate pOH of a buffer from Kb (Henderson Hasselbalch equation)")
    print("2: Calculate pH of a buffer from Ka (Henderson Hasselbalch equation)")
    print("3: Calculate the ratio of base/acid from pH and Ka")
    print("4: Solve an ICE table")
    choice = input("What would you like to do?:  ")
    if choice == "1":
        basehenderson()
    if choice == "2":
        acidhenderson()
    if choice == "3":
        acid_base_ratio()
    if choice == "4":
        icesolver()
    if choice == "exit" or "quit":
        return
main()

def scientific_string(string):
    string_list = list(string)
    i = 0
    while i < len(string_list):
        if string_list[i] == "^":
            string_list[i] = "**"
            return_var = ''.join(string_list)
            return eval(return_var)
        i = i + 1
    return_var = ''.join(string_list)
    return eval(return_var)

If I input the number 2, it should go to the function acidhenderson() (I didn't put the other functions as it would take a lot of room), but instead in linux it just returns to the next line like this:

root@debian:~/Documents/code/eq# python equilibrium.py 
1: Calculate pOH of a buffer from Kb (Henderson Hasselbalch equation)
2: Calculate pH of a buffer from Ka (Henderson Hasselbalch equation)
3: Calculate the ratio of base/acid from pH and Ka
4: Solve an ICE table
What would you like to do?:  2
root@debian:~/Documents/code/eq#

I am relatively new to Linux but I'm thinking that this may be a Linux problem rather than a python code problem but I'm not too sure. Can anyone help?

Are you using python 2? You can check with `import sys; print(sys.version)`. — Aran-Fey, Mar 13 '19 at 08:18
show us scientific_string() as your code seems to execute OK with python 3.7. — naivepredictor, Mar 13 '19 at 08:21
@Aran-Fey if it was python 2 wouldnt the prints not work since they have parenthesis? — Demitech, Mar 13 '19 at 08:21
I'd guess you are using Python 2. But you need to do some basic debugging. Like basic debugging prints, e.g. `print(repr(choice))`, or `print(type(choice))`. — juanpa.arrivillaga, Mar 13 '19 at 08:22
@Demitech they would work just fine. `("some string")` is a valid expression, it is equivalent to `"some string"`, and the python 2 `print` statement would happy accept that expression — juanpa.arrivillaga, Mar 13 '19 at 08:22
add else statement and print something in it to see if you enter else. — naivepredictor, Mar 13 '19 at 08:24
it does matter if you enter string or integer and compare it with string. — naivepredictor, Mar 13 '19 at 08:24
@Demitech dude, almost certainly you are running Python 2. Just check. — juanpa.arrivillaga, Mar 13 '19 at 08:25
I guess Im just stupid: I assumed that since python 3 was on my windows computer that it would be the same for the updated version of debian on this other laptop, however, print(sys.version) returned 2.7.16rc1 (default, Feb 18 2019, 11:05:09). — Demitech, Mar 13 '19 at 08:29

score -2 · Accepted Answer · answered Mar 13 '19 at 08:26

-2

Best shot, you're using:

Python 2.x:

choice = raw_input("What would you like to do?:  ")  # to have the input in str
if choice == "1":
    basehenderson()
if choice == "2":
    acidhenderson()
if choice == "3":
    acid_base_ratio()
if choice == "4":
    icesolver()
if choice == "exit" or "quit":
    return

answered Mar 13 '19 at 08:26

DirtyBit

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Apparently, I was using 2.x and all I had to do to fix it was run python3 [filename] as I guess the default is to run 2.x since Debian comes preinstalled with both 2 and 3. – Demitech Mar 13 '19 at 08:38

Python input() function not functioning properly: doesn't seem to record any input. Maybe it's a Linux issue?

1 Answers1