# 三維標量場觀察器 相關文檔： [_將Mayavi嵌入到界面中_](mlab_and_mayavi.html#sec-mayavi-embed)  ``` # -*- coding: utf-8 -*- import numpy as np from numpy import * from enthought.traits.api import * from enthought.traits.ui.api import * from enthought.tvtk.pyface.scene_editor import SceneEditor from enthought.mayavi.tools.mlab_scene_model import MlabSceneModel from enthought.mayavi.core.ui.mayavi_scene import MayaviScene class FieldViewer(HasTraits): """三維標量場觀察器""" # 三個軸的取值范圍 x0, x1 = Float(-5), Float(5) y0, y1 = Float(-5), Float(5) z0, z1 = Float(-5), Float(5) points = Int(50) # 分割點數 autocontour = Bool(True) # 是否自動計算等值面 v0, v1 = Float(0.0), Float(1.0) # 等值面的取值范圍 contour = Range("v0", "v1", 0.5) # 等值面的值 function = Str("x*x*0.5 + y*y + z*z*2.0") # 標量場函數 plotbutton = Button(u"描畫") scene = Instance(MlabSceneModel, ()) # mayavi場景 view = View( HSplit( VGroup( "x0","x1","y0","y1","z0","z1", Item('points', label=u"點數"), Item('autocontour', label=u"自動等值"), Item('plotbutton', show_label=False), ), VGroup( Item(name='scene', editor=SceneEditor(scene_class=MayaviScene), # 設置mayavi的編輯器 resizable=True, height=300, width=350 ), 'function', Item('contour', editor=RangeEditor(format="%1.2f", low_name="v0", high_name="v1") ), show_labels=False ) ), width = 500, resizable=True, title=u"三維標量場觀察器" ) def _plotbutton_fired(self): self.plot() def _autocontour_changed(self): "自動計算等值平面的設置改變事件響應" if hasattr(self, "g"): self.g.contour.auto_contours = self.autocontour if not self.autocontour: self._contour_changed() def _contour_changed(self): "等值平面的值改變事件響應" if hasattr(self, "g"): if not self.g.contour.auto_contours: self.g.contour.contours = [self.contour] def plot(self): "繪制場景" # 產生三維網格 x, y, z = mgrid[ self.x0:self.x1:1j*self.points, self.y0:self.y1:1j*self.points, self.z0:self.z1:1j*self.points] scalars = eval(self.function) # 根據函數計算標量場的值 self.scene.mlab.clf() # 清空當前場景 # 繪制等值平面 g = self.scene.mlab.contour3d(x, y, z, scalars, contours=8, transparent=True) g.contour.auto_contours = self.autocontour self.scene.mlab.axes() # 添加坐標軸 # 添加一個X-Y的切面 s = self.scene.mlab.pipeline.scalar_cut_plane(g) cutpoint = (self.x0+self.x1)/2, (self.y0+self.y1)/2, (self.z0+self.z1)/2 s.implicit_plane.normal = (0,0,1) # x cut s.implicit_plane.origin = cutpoint self.g = g self.scalars = scalars # 計算標量場的值的范圍 self.v0 = np.min(scalars) self.v1 = np.max(scalars) app = FieldViewer() app.configure_traits() ```