import "../selection/select";

import "transition";

d3_transitionPrototype.select = function(selector) {

var id = this.id,

ns = this.namespace,

subgroups = [],

subgroup,

subnode,

node;

selector = d3_selection_selector(selector);

for (var j = -1, m = this.length; ++j < m;) {

subgroups.push(subgroup = []);

for (var group = this[j], i = -1, n = group.length; ++i < n;) {

if ((node = group[i]) && (subnode = selector.call(node, node.__data__, i, j))) {

if ("__data__" in node) subnode.__data__ = node.__data__;

d3_transitionNode(subnode, i, ns, id, node[ns][id]);

subgroup.push(subnode);

} else {

subgroup.push(null);

}

}

}

return d3_transition(subgroups, ns, id);

};