AngularJS Sortable order pricing issue - angularjs

Question

I'm facing an issue when ordering prices formatted as currency.
var myApp = angular.module("myApp", []);
myApp.factory("Purchases", function() {
var Purchases = {};
Purchases.data = [{
date: "10/05/2012",
text: "1 Lorem ipsum dolor sit amet ipsum dolor",
price: "£90",
availability: "1 Available until 10th Dec 2013"
},
{
date: "24/05/2012",
text: "2 Lorem ipsum dolor sit amet ipsum dolor",
price: "£9.5",
availability: "2 Available until 10th Dec 2013"
},
{
date: "20/05/2012",
text: "3 Lorem ipsum dolor sit amet ipsum dolor",
price: "£10",
availability: "3 Available until 10th Dec 2013"
}
];
return Purchases;
});
function PurchasesCtrl($scope, Purchases) {
$scope.purchases = Purchases;
$scope.sort = {
column: '',
descending: false
};
$scope.changeSorting = function(column) {
var sort = $scope.sort;
if (sort.column == column) {
sort.descending = !sort.descending;
} else {
sort.column = column;
sort.descending = false;
}
};
}
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp">
<div ng-controller="PurchasesCtrl">
<h2>Purchases:</h2>
<table cellspacing="0">
<tr class="first">
<th class="first" ng-click="changeSorting('date')">Date</th>
<th ng-click="changeSorting('text')">Description</th>
<th ng-click="changeSorting('price')">Amount</th>
<th ng-click="changeSorting('availability')">Status</th>
</tr>
<tr ng-repeat="purchase in purchases.data|orderBy:sort.column:sort.descending">
<td class="first">{{purchase.date}}</td>
<td>{{purchase.text}}</td>
<td>{{purchase.price}}</td>
<td>{{purchase.availability}}</td>
</tr>
</table>
</div>
</div>
The issue order: $9.5 > $10
Is there any way to correct the ordering?

Answer 1

Yes, check this fiddle: http://jsfiddle.net/2u3wn91z/1/ .
You want to compare numbers, not strings, so you need to separate currency (as first letter of price) and then remove currency from price):
Purchases.data = Purchases.data.map(function (purchase) {
purchase.currency = purchase.price.charAt(0);
purchase.price = Number(purchase.price.substr(1));
return purchase;
});
$scope.purchases = Purchases;
When you have price separated from currency, you can display it separately:
<td>{{purchase.currency}}{{purchase.price}}</td>