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JavaScript

olu adesina
olu adesina
23,007 Points
Posted by olu adesina
olu adesina
23,007 Points

im trying to get an average from an array where am i going wrong?

age = [30, 23, 34, 32]
averageAge = 0

function getAverageAge(x, y) {
    for (i = 0; i < x.length; i += 1) {

        x[i] += y

    }
    return y / x.length
}
getAverageAge(age, averageAge)

2 Answers

Sahil Kapoor
Sahil Kapoor
8,932 Points
Sahil Kapoor
Sahil Kapoor
8,932 Points 
x[i] += y;
x[i] = x[i] + y;
// The above Two lines of code are equivalent and they means you are adding y in every element of x array any y is zero 

// The correct way is 
y += x[i];
y = y + x[i];
// The above two lines of code are equivalent and the means that you are adding every element of x array in y variable
olu adesina
olu adesina
23,007 Points
olu adesina
olu adesina
23,007 Points

thanks for this but just want ask why it matters the order

Sahil Kapoor
Sahil Kapoor
8,932 Points
Sahil Kapoor
Sahil Kapoor
8,932 Points

The interpreter computes the expression on the right side of equal "=" and then store it in the variable on the left side left side. That's why order matters in every programming language.

martinjones1
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
martinjones1
Front End Web Development Techdegree Graduate 44,819 Points
martinjones1
.a{fill-rule:evenodd;}techdegree seal-36
martinjones1
Front End Web Development Techdegree Graduate 44,819 Points

I updated your JS to that below which seems to work OK, I would use console.log as often as possible to help debug your scripts and see if things are working as expected:

var age = [30, 23, 34, 32];
var averageAge = 0;

function getAverageAge(x, y) {
    for (var i = 0; i < x.length; i++) {
        averageAge += x[i];
    }
     averageAge /= x.length;
    console.log(averageAge); // can use return averageAge instead
}
getAverageAge(age, averageAge);