Error in undo(plot(a, aes(Nadir, mgam.lr1$yhat), se = T)) : could not find function "undo"

This error message indicates that the function "undo" is not recognized by R. It is possible that the function was not properly installed or loaded into the R environment. To resolve this issue, try installing or loading the package that contains the "undo" function. Alternatively, you may need to define or create the "undo" function yourself.

相关问题

File "C:\Users\86187\AppData\Local\Programs\Python\Python38\lib\tkinter\__init__.py", line 1895, in __call__ return self.func(*args) File "D:/Universityclassinfoe/Python/Goband/MYGOBAND.py", line 91, in <lambda> self.undo_button = Button(self._root, text='悔棋', command=lambda: self._undo(),state=DISABLED) File "D:/Universityclassinfoe/Python/Goband/MYGOBAND.py", line 111, in _undo if self._board.undo(): File "D:/Universityclassinfoe/Python/Goband/MYGOBAND.py", line 37, in undo self._board = self._board_states.pop() IndexError: pop from empty list

这个错误是由于在MYGOBAND.py文件中的_undo()方法中，尝试从空列表中弹出元素所引起的。具体地说，_board_states列表是一个记录棋盘状态的列表，每当玩家落定一步棋时，就会将当前的棋盘状态添加到该列表中。而在执行悔棋操作时，_undo()方法会将列表中最后一个棋盘状态弹出并将其用作当前棋盘状态。但是，当列表为空时，尝试弹出元素会引发IndexError异常。

要解决这个问题，您可以在执行悔棋操作之前，确保_board_states列表中至少有一个元素。例如，您可以在_undo()方法的开头添加以下代码：

if not self._board_states:
    return

这将检查_board_states列表是否为空。如果是，它将提前返回，而不会尝试执行悔棋操作。如果列表不为空，则可以继续执行原始的_undo()方法，而不会引发IndexError异常。

// 初始化gojs布局相关 function ContinuousForceDirectedLayout() { go.ForceDirectedLayout.call(this); this._isObserving = false; } go.Diagram.inherit(ContinuousForceDirectedLayout, go.ForceDirectedLayout); // 初始化gojs function initGraph() { var $ = go.GraphObject.make; myDiagram = $(go.Diagram, 'myDiagramDiv', { 'toolManager.mouseWheelBehavior': go.ToolManager.WheelZoom, initialContentAlignment: go.Spot.Center, hasHorizontalScrollbar: false, hasVerticalScrollbar: false, 'undoManager.isEnabled': true, 'draggingTool.isGridSnapEnabled': true, layout: $(ContinuousForceDirectedLayout, { arrangesToOrigin: true, defaultSpringLength: 30, defaultElectricalCharge: 100 }), SelectionMoved: function (e) { e.diagram.layout.invalidateLayout(); } });在这段代码基础上增加水平引力，让让元素横向排布

可以在 ContinuousForceDirectedLayout 的构造函数中添加一个新的属性 horizontalGravity，表示元素之间的横向引力：

function ContinuousForceDirectedLayout() {
  go.ForceDirectedLayout.call(this);
  this._isObserving = false;
  this.horizontalGravity = 0.5;
}

然后在计算布局时，将横向引力添加到计算过程中：

ContinuousForceDirectedLayout.prototype.doLayout = function(coll) {
  var diagram = this.diagram;
  if (diagram === null) return;
  if (coll === null) coll = this.collectParts();
  var root = this.findRoots();
  var v = this.createVertexes(coll);
  var e = this.createEdges(coll);
  this.initValues(v, e, root);
  this.computeEffectiveLengths(v, e);
  this.iterateLayout(v, e);
  this.updateParts(v);
  this.invalidateLinks();
  // Add horizontal gravity
  this.addHorizontalGravity(v, e);
  this.setToCenter(v);
};

其中 addHorizontalGravity 函数的实现如下：

ContinuousForceDirectedLayout.prototype.addHorizontalGravity = function(vertexes, edges) {
  var gravity = this.horizontalGravity;
  for (var i = 0; i < vertexes.length; i++) {
    var v = vertexes[i];
    for (var j = i + 1; j < vertexes.length; j++) {
      var u = vertexes[j];
      if (!v || !u) continue;
      var dx = u.location.x - v.location.x;
      var dy = u.location.y - v.location.y;
      var d = Math.sqrt(dx * dx + dy * dy);
      var fx = dx * gravity;
      var fy = dy * gravity;
      v.dx += fx;
      v.dy += fy;
      u.dx -= fx;
      u.dy -= fy;
    }
  }
};

这个函数会遍历所有的节点对，并计算它们之间的横向引力，然后添加到节点的 dx 和 dy 属性中。最后在 iterateLayout 函数中，这个 dx 和 dy 属性会被用来更新节点的位置。