template/html/d3-graph.js
function setNodesFixed(fixed)
   {
      // Resets any fixed node state.
      if (nodes) { nodes.each(function(node) { d3.select(this).classed('fixed', node.fixed = fixed); }); }

      // Copy existing sim data to any package scope that contains the same node ID.
      for (var key in dataPackageMap) { dataPackageMap[key].nodes.forEach(function(node) { node.fixed = fixed; }); }

      if (data) { data.allNodesFixed = fixed; }
   }
function setNodesFixed(fixed)
   {
      // Resets any fixed node state.
      if (nodes) { nodes.each(function(node) { d3.select(this).classed('fixed', node.fixed = fixed); }); }

      // Copy existing sim data to any package scope that contains the same node ID.
      for (var key in dataPackageMap) { dataPackageMap[key].nodes.forEach(function(node) { node.fixed = fixed; }); }

      if (data) { data.allNodesFixed = fixed; }
   }
Sets all nodes fixed (freeze) or unfixed (unfreeze).

@param {boolean}  fixed - Fixed state for all nodes.