I need to use ng-repeat (in AngularJS)  to list all of the elements in an array.
The complication is that each element of the array will transform to ei
for a solution that really works
html
<remove  ng-repeat-start="itemGroup in Groups" ></remove>
   html stuff in here including inner repeating loops if you want
<remove  ng-repeat-end></remove>
add an angular.js directive
//remove directive
(function(){
    var remove = function(){
        return {    
            restrict: "E",
            replace: true,
            link: function(scope, element, attrs, controller){
                element.replaceWith('<!--removed element-->');
            }
        };
    };
    var module = angular.module("app" );
    module.directive('remove', [remove]);
}());
for a brief explanation,
ng-repeat binds itself to the <remove> element and loops as it should, and because we have used ng-repeat-start / ng-repeat-end it loops a block of html not just an element.
then the custom remove directive places the <remove> start and finish elements with <!--removed element-->
As of AngularJS 1.2 there's a directive called ng-repeat-start that does exactly what you ask for. See my answer in this question for a description of how to use it.
You might want to flatten the data within your controller:
function MyCtrl ($scope) {
  $scope.myData = [[1,2,3], [4,5,6], [7,8,9]];
  $scope.flattened = function () {
    var flat = [];
    $scope.myData.forEach(function (item) {
      flat.concat(item);
    }
    return flat;
  }
}
And then in the HTML:
<table>
  <tbody>
    <tr ng-repeat="item in flattened()"><td>{{item}}</td></tr>
  </tbody>
</table>
The above is correct but for a more general answer it is not enough. I needed to nest ng-repeat, but stay on the same html level, meaning write the elements in the same parent. The tags array contain tag(s) that also have a tags array. It is actually a tree.
[{ name:'name1', tags: [
  { name: 'name1_1', tags: []},
  { name: 'name1_2', tags: []}
  ]},
 { name:'name2', tags: [
  { name: 'name2_1', tags: []},
  { name: 'name2_2', tags: []}
  ]}
]
So here is what I eventually did.
<div ng-repeat-start="tag1 in tags" ng-if="false"></div>
    {{tag1}},
  <div ng-repeat-start="tag2 in tag1.tags" ng-if="false"></div>
    {{tag2}},
  <div ng-repeat-end ng-if="false"></div>
<div ng-repeat-end ng-if="false"></div>
Note the ng-if="false" that hides the start and end divs.
It should print
name1,name1_1,name1_2,name2,name2_1,name2_2,
If you use ng > 1.2, here is an example of using ng-repeat-start/end without generating unnecessary tags:
<html>
  <head>
    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
    <script>
      angular.module('mApp', []);
    </script>
  </head>
  <body ng-app="mApp">
    <table border="1" width="100%">
      <tr ng-if="0" ng-repeat-start="elem in [{k: 'A', v: ['a1','a2']}, {k: 'B', v: ['b1']}, {k: 'C', v: ['c1','c2','c3']}]"></tr>
      <tr>
        <td rowspan="{{elem.v.length}}">{{elem.k}}</td>
        <td>{{elem.v[0]}}</td>
      </tr>
      <tr ng-repeat="v in elem.v" ng-if="!$first">
        <td>{{v}}</td>
      </tr>
      <tr ng-if="0" ng-repeat-end></tr>
    </table>
  </body>
</html>The important point: for tags used for ng-repeat-start and ng-repeat-end set ng-if="0", to let not be inserted in the page. In this way the inner content will be handled exactly as it is in knockoutjs (using commands in <!--...-->), and there will be no garbage.
<table>
  <tbody>
    <tr><td>{{data[0].foo}}</td></tr>
    <tr ng-repeat="d in data[1]"><td>{{d.bar}}</td></tr>
    <tr ng-repeat="d in data[2]"><td>{{d.lol}}</td></tr>
  </tbody>
</table>
I think that this is valid :)