Calculate average from list of values in JSON

Question

I have a simple ng-repeat that displays a list of values (financial income). How can i calculate the average from this list?

<div ng-repeat="data in MyData">
    {{ data.income }}
</div>
<div>
    Average:
</div>

Which displays:

11
14
8
9
21
10
2
1
5
13

Thanks

Solution

I don't think this is related to AngularJS. You need to create a function who calculates your average and then :

<div ng-repeat="data in MyData">
    {{ data.income }}
</div>
<div>
    Average: {{ myAveragingFunction(MyData) }}
</div>

Comments

[agershun]

Probably the parameter of myAverageFunction should be "MyData", not "data", like "myAveragingFunction(MyData)"

[RamblerToning]

You're commenting out the closing bracket on the for loop there too

[James Bell]

But isn't your filter expecting an array when that HTML is sending an integer? And also, isn't the last "data" outside the ng-repeat loop?

[SirTophamHatt]

Typo in the HTML. Assuming MyData is an array of integers and not a collection of objects, you would ng-repeat over MyData and passed MyData to the average filter. If MyData were a structure like the Controller example, then you'd iterate over MyData.income and output MyData.average outside the ng-repeat block.

[SirTophamHatt]

Since none of these examples consider that his array is a collection, he's better off changing his structure or writing a function to accept a collection and sum the .income property.

[tomasbedrich]

What about if MyData.length is 0?

[Matt Westlake]

@tomasbedrich if myData.length == 0 then 0 < 0 is false and it will skip the for loop. The problem is when you get to var avg = 0/0 which is 'undefined'