【发布时间】：2011-01-14 19:28:02
【问题描述】：
我刚刚开始尝试使用 Matplotlib 的动画功能来制作一个类似于 Google Finance 的图表。
我结合了我在项目网站上找到的两个示例（Draggable rectangle exercise、api example code: date_demo.py）并对它们进行了一些调整以得出底部列出的代码。
虽然看起来还不错，但我希望顶部图表（主）随着底部图表（从）选择的移动而动态更新，而不仅仅是在底部选择被释放时。我怎样才能做到这一点？我试图将self.rect.figure.canvas.draw() 位移动到on_motion 方法，但它似乎干扰了 blit 的东西，因为底部选择不会正确呈现。
所以我认为解决方案是为底部图表制作智能动画，即 blit-ing 位，而顶部图表则完全重新绘制。问题是我可以重绘任何东西的唯一方法是重新绘制整个画布，这将包括底部图表。我确实找到了matplotlib.axes 的draw() 方法，但我无法让它工作。正如我上面所说的，最好我只想重新绘制顶部图表，而底部的图表则以巧妙的方式进行调整。有谁知道怎么做？
到目前为止，这是我的代码。请原谅代码，它有点不整洁。
import datetime
import numpy as np
import sys
import time
import wx
import matplotlib
from matplotlib.figure import Figure
import matplotlib.dates as mdates
import matplotlib.ticker as mtickers
from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
import matplotlib.patches as mpatches
class DraggableRectangle:
lock = None
def __init__(self, rect, master, xMin, xMax):
self.rect = rect
self.press = None
self.background = None
self.xMax = xMax
self.xMin = xMin
self.master = master
def connect(self):
self.cidpress = self.rect.figure.canvas.mpl_connect('button_press_event', self.on_press)
self.cidrelease = self.rect.figure.canvas.mpl_connect('button_release_event', self.on_release)
self.cidmotion = self.rect.figure.canvas.mpl_connect('motion_notify_event', self.on_motion)
def on_press(self, event):
if event.inaxes != self.rect.axes: return
if DraggableRectangle.lock is not None: return
contains, attrd = self.rect.contains(event)
if not contains: return
x0, y0 = self.rect.xy
self.press = x0, y0, event.xdata, event.ydata
DraggableRectangle.lock = self
canvas = self.rect.figure.canvas
axes = self.rect.axes
self.rect.set_animated(True)
canvas.draw()
self.background = canvas.copy_from_bbox(self.rect.axes.bbox)
axes.draw_artist(self.rect)
canvas.blit(axes.bbox)
def on_motion(self, event):
if DraggableRectangle.lock is not self: return
if event.inaxes != self.rect.axes: return
x0, y0, xpress, ypress = self.press
dx = event.xdata - xpress
dy = 0
if x0+dx > self.xMax:
self.rect.set_x(self.xMax)
elif x0+dx < self.xMin:
self.rect.set_x(self.xMin)
else:
self.rect.set_x(x0+dx)
self.rect.set_y(y0+dy)
canvas = self.rect.figure.canvas
axes = self.rect.axes
canvas.restore_region(self.background)
self.master.set_xlim(self.rect.get_x(), self.rect.get_x() + 92)
axes.draw_artist(self.rect)
canvas.blit(axes.bbox)
def on_release(self, event):
if DraggableRectangle.lock is not self: return
self.press = None
DraggableRectangle.lock = None
self.rect.set_animated(False)
self.background = None
self.rect.figure.canvas.draw()
def disconnect(self):
self.rect.figure.canvas.mpl_disconnect(self.cidpress)
self.rect.figure.canvas.mpl_disconnect(self.cidrelease)
self.rect.figure.canvas.mpl_disconnect(self.cidmotion)
class MplCanvasFrame(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, wx.ID_ANY, title='First Chart', size=(800, 700))
datafile = matplotlib.get_example_data('goog.npy')
r = np.load(datafile).view(np.recarray)
datesFloat = matplotlib.dates.date2num(r.date)
figure = Figure()
xMaxDatetime = r.date[len(r.date)-1]
xMinDatetime = r.date[0]
xMaxFloat = datesFloat[len(datesFloat)-1]
xMinFloat = datesFloat[0]
yMin = min(r.adj_close) // 5 * 5
yMax = (1 + max(r.adj_close) // 5) * 5
master = figure.add_subplot(211)
master.plot(datesFloat, r.adj_close)
master.xaxis.set_minor_locator(mdates.MonthLocator())
master.xaxis.set_major_locator(mdates.MonthLocator(bymonth=(1,4,7,10)))
master.xaxis.set_major_formatter(mdates.DateFormatter('%b-%y'))
master.set_xlim(datesFloat[120], datesFloat[120]+92)
master.yaxis.set_minor_locator(mtickers.MultipleLocator(50))
master.yaxis.set_major_locator(mtickers.MultipleLocator(100))
master.set_ylim(yMin, yMax)
master.set_position([0.05,0.20,0.92,0.75])
master.xaxis.grid(True, which='minor')
master.yaxis.grid(True, which='minor')
slave = figure.add_subplot(212, yticks=[])
slave.plot(datesFloat, r.adj_close)
slave.xaxis.set_minor_locator(mdates.MonthLocator())
slave.xaxis.set_major_locator(mdates.YearLocator())
slave.xaxis.set_major_formatter(mdates.DateFormatter('%b-%y'))
slave.set_xlim(xMinDatetime, xMaxDatetime)
slave.set_ylim(yMin, yMax)
slave.set_position([0.05,0.05,0.92,0.10])
rectangle = mpatches.Rectangle((datesFloat[120], yMin), 92, yMax-yMin, facecolor='yellow', alpha = 0.4)
slave.add_patch(rectangle)
canvas = FigureCanvas(self, -1, figure)
drag = DraggableRectangle(rectangle, master, xMinFloat, xMaxFloat - 92)
drag.connect()
app = wx.PySimpleApp()
frame = MplCanvasFrame()
frame.Show(True)
app.MainLoop()
【问题讨论】：
-
我没有答案，但情节很酷！
-
是的，整个动画在 Matplotlib 中运行得非常好。如果我能弄清楚最后一部分，我会更喜欢它；）
标签： animation matplotlib