function calculateArea(r){
var area;
if (r<=0){
return 0;
} else {
area=Math.PI*r*r;
return area;
}
}
var radius = 5.2;
var theArea=calculateArea(radius);
console.log("Area = " + theArea); New here, please let me know if I have posted incorrectly.
If the initialization of a variable is a function. Does the function execute automatically? For instance, see my code below. I get the desired output in the console log. Had I not included this function in the variable, would it have still ran?
function calculateArea(r){
var area;
if (r<=0){
return 0;
} else {
area=Math.PI*r*r;
return area;
}
}
var radius = 5.2;
var theArea=calculateArea(radius);
console.log("Area = " + theArea);
EDIT: Think I've got my head wrapped around this not. Thank you all!
if you call it without any arguments
calculateArea()
r will be undefined, leading to Math.PI * r * r = number * undefined = NaN
and if you never used this
var theArea=calculateArea(radius);
then the function won't be executed automatically
No, defining a function doesn't run it automatically. (After all, if it requires an argument, like r in your case, what would that r be?)
You will need to call the function (calculateArea(1)) for it to be run, but you don't need to assign the return value to a variable (area = calculateArea(1)) for that to happen.