[Tutor] Help on Python

[Cameron Simpson]

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On 15Oct2019 20:20, Tyson Barber <tysonwbarber at gmail.com> wrote:
>Sorry about the confusion of my last email, this is my first time using
>this method of help.
>
>I have tweaked the code slightly to look like this:
>
>income = (input("Please enter the income: "))
>cost = int(input("Please enter the cost: "))
>if income >= cost :
>        print (income - cost == profit)
>else:
>    income < cost :
>        print (cost - income == loss)
>
>in the line after the else statement, it is giving me an error message of
>invalid syntax (where the red is).

This is a plain text mailing list. There are no colour here. I expect 
your error message concenrs this line:

    income < cost :

That is not a legal Python statement (hence the error). It should look 
like this:

    if income < cost :

However, because it is immediate in the "else" part Python has a 
convenient shorter version, where you replace this:

    else:
        if income < cost :
            print (cost - income == loss)

with this:

    elif income < cost :
            print (cost - income == loss)

The other point (already made by someone else in this list) is that:

    income < cost

is the dual of:

    income >= cost

so you don't really need the second test at all. You could just write:

if income >= cost :
        print (income - cost == profit)
else:
        print (cost - income == loss)

because in the "else" part it _must_ already be the case that income < 
cost.

Cheers,
Cameron Simpson <cs at cskk.id.au>