Angular - update a table cell - angularjs

Question

In my angular app I have the typical table iterator via ng-repeat.
<table class="table table-bordered table-condensed table-striped">
<tbody>
<tr ng-repeat="assay in assays">
<td>
<td key="id">{{assay.id}}</td>
<td key="source">{{assay.source}}</td>
<td key="status">{{assay.status}}</td>
... etc ...
</tr>
</tbody>
</table>
Using a button a user makes a change in a modal dialog. This is all working fine, but I want to update a single cell in the table with the result; I have the id of the row as well as the field name.
Is it possible in Angular to access a single cell, or even update the entire row, if you have the index? At present I am achieving this by refreshing all the table data from the remote server... not ideal.
I guess I am looking for something like:
assays[id].status = 'great!'

Answer 1

Thanks to #JB Nizet 's comment above I was able to achieve what I wanted, I think in a more angular way than I had been headed in. The angular data binding is really a great way to handle model/view updates.
I have posted a simplified version of the code here in case it helps someone else. I am using AngularUI for the modals.
view
<table class="table table-bordered table-condensed table-striped">
<tbody>
<tr ng-repeat="assay in assays">
<td>
<td key="id">{{assay.id}}</td>
<td key="source">{{assay.source}}</td>
<td key="status">{{assay.status}}</td>
... etc ...
<button class="btn btn-xs btn-info" ng-click="invokeAssayModal(assay)">Assay</button>
</tr>
</tbody>
</table>
controller
$scope.invokeAssayModal = (assay) ->
$scope.assay = assay
modalInstance = $modal.open(
templateUrl: '/templates/panel/assay_modal.html'
controller: 'AssayModalCtrl'
windowClass: 'configure-dialog'
resolve:
assay: ->
$scope.assay
)
modalInstance.result.then ((assay) ->
$scope.assay = assay
return
), ->
return
modal view
<button type="button" class="btn btn-mini btn-success" ng-click="select(primerPair)">Select</button>
modal controller
$scope.select = (primerPair) ->
$scope.assay.source = primerPair.source