As far as I understood your question, you'd like to have something like that:
<table ng-repeat="group in data">
<thead>
<th> {{group.name}} </th>
</thead>
<tbody ng-repeat="item in group.items">
<tr>
<td>{{getIndex($parent.$index - 1, $index)}} | {{item}} </td>
</tr>
</tbody>
</table>
$scope.data = [
{name: 'Group1', items: ['a','b']},
{name: 'Group2', items: [1,2,3]},
{name: 'Group3', items: ['x', 'xx', 'xxx', 'xxxx']}
];
$scope.getIndex = function(previousGroupIndex, currentItemIndex){
if(previousGroupIndex >= 0){
var previousGroupLength = getPreviousItemsLength(previousGroupIndex);
return previousGroupLength + currentItemIndex;
}
return currentItemIndex;
};
function getPreviousItemsLength(currentIndex){
var length = 0;
for (var i = 0; i <= currentIndex; i++){
length += $scope.data[i].items.length;
}
return length;
// or even better to use Array.prototype.reduce() for that purpose
// it would be shorter and beautiful
// return $scope.data.reduce(function(previousValue, currentGroup, index){
// return index <= previousGroupIndex ? previousValue + currentGroup.items.length : previousValue;
// }, 0);
}
You need to play with $parent.$index property and use some math :) in order to achieve that.
It would look like the following:

Check out this JSFiddle to see live example.