Apple to Raspberry Pi: Python’s If

appleberryIn Objective-C, we would write an if statement like this:

if(number1 == number2){
    NSLog(@"equal");
}

in Python it is this:

if number1==number2 :
    print('equal')

There is no parentheses required around the logical expression. Instead of the {} to show the block to run, a colon (:)  and indentations  find the code to run. Note that if you feel comfy putting parentheses around your logical expression, go ahead. Python will not complain.

A simple else statement is not more than that:

if (number1 == number2):
    print('equal')
else:
    print('not equal')

Python gets a little different when there is more than one else. Python uses the elif operator , which stands for else if.  Instead of this in XCode:

if (number1 == number2) {
   NSLog(@"equal");
}
else if(number1 > number2){
    NSLog(@"greater");
}
else if( number1 < number2){
    NSLog(@"less");
else{
    NSLog(@"error");
}

We have in Python:

if number1 == number2:
    print('equal')
elif number1 > number2:
    print('greater')
elif number1 < number2:
    print('less')
else:
    print('error')

Note the use of else here. Else is actually not required for chains of elif, but its use would be the same as default in a switch…case…default statement.

switch(number2){
case 1:
    //stuff
    break;
case 2:
    //more stuff
    break;
case 3:{
    //even more stuff
    break;
default:
    //none of that stuff, most likely an error.
    break;
}

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