使用PyQtGraph绘制精美的股票行情K线图的示例代码

pyqtgraph是Python平台上一种功能强大的2D/3D绘图库，相对于matplotlib库，由于其在内部实现方式上，使用了高速计算的numpy信号处理库以及Qt的GraphicsView框架，因此它在大数据量的处理及快速显示方面有着天然的优势，非常适合于需要快速绘图更新、视频或实时交互性的操作场合，在数学、科学和工程领域都有着广泛的应用。

K线图介绍

对于股票交易者来讲，K线图是弄清股票一段时间走势的一种最基本的图形工具，K线分为阳线和阴线，阳线和阴线都包含了开盘价、收盘价、最高价和最低价，一般K线如下图所示：

当收盘价大于开盘价时，称为阳线，在图形上一般用红色表示，反之，当收盘价低于开盘价时，称为阴线，在图形上一般用绿色表示。由于其形状颇似一根根蜡烛，K线图有时也叫做蜡烛图。

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'QWidget_plot.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!

import sys
reload(sys)
sys.setdefaultencoding('utf-8')
from PyQt4 import QtCore, QtGui
import datetime
import pyqtgraph as pg
import tushare as ts

try:
  _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
  def _fromUtf8(s):
    return s

try:
  _encoding = QtGui.QApplication.UnicodeUTF8
  def _translate(context, text, disambig):
    return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
  def _translate(context, text, disambig):
    return QtGui.QApplication.translate(context, text, disambig)

class Ui_MainWindow(object):
  def setupUi(self, MainWindow):
    MainWindow.setObjectName(_fromUtf8("MainWindow"))
    MainWindow.resize(800, 600)
    self.centralwidget = QtGui.QWidget(MainWindow)
    self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
    self.verticalLayout_2 = QtGui.QVBoxLayout(self.centralwidget)
    self.verticalLayout_2.setObjectName(_fromUtf8("verticalLayout"))
    self.verticalLayout_2.setObjectName(_fromUtf8("verticalLayout_2"))
    self.verticalLayout_2.setContentsMargins(0, 0, 0, 0)
    MainWindow.setCentralWidget(self.centralwidget)
    self.menubar = QtGui.QMenuBar(MainWindow)
    self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 31))
    self.menubar.setObjectName(_fromUtf8("menubar"))
    MainWindow.setMenuBar(self.menubar)

    self.drawChart = DrawChart(ktype='D')
    self.verticalLayout_2.addWidget(self.drawChart.pyqtgraphDrawChart())

    self.retranslateUi(MainWindow)
    QtCore.QMetaObject.connectSlotsByName(MainWindow)

  def retranslateUi(self, MainWindow):
    MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))

class DrawChart():
  def __init__(self, code='sz50', start=str(datetime.date.today() - datetime.timedelta(days=200)), end=str(datetime.date.today() + datetime.timedelta(days=1)), ktype='D'):
    self.code = code
    self.start = start
    self.end = end
    self.ktype = ktype
    self.data_list, self.t = self.getData()

  def pyqtgraphDrawChart(self):
    try:
      self.item = CandlestickItem(self.data_list)
      self.xdict = {0: str(self.hist_data.index[0]).replace('-', '/'), int((self.t + 1) / 2) - 1: str(self.hist_data.index[int((self.t + 1) / 2)]).replace('-', '/'), self.t - 1: str(self.hist_data.index[-1]).replace('-', '/')}
      self.stringaxis = pg.AxisItem(orientation='bottom')
      self.stringaxis.setTicks([self.xdict.items()])
      self.plt = pg.PlotWidget(axisItems={'bottom': self.stringaxis}, enableMenu=False)

      self.plt.addItem(self.item)
      # self.plt.showGrid(x=True, y=True)

      return self.plt
    except:
      return pg.PlotWidget()

  def getData(self):
    self.start = str(datetime.date.today() - datetime.timedelta(days=150))
    self.end = str(datetime.date.today() + datetime.timedelta(days=1))
    self.hist_data = ts.get_hist_data(self.code, self.start, self.end, self.ktype).sort_index()[-300:-1]
    data_list = []
    t = 0
    for dates, row in self.hist_data.iterrows():
      open, high, close, low, volume, price_change, p_change, ma5, ma10, ma20 = row[:10]
      datas = (t, open, close, low, high, volume, price_change, p_change, ma5, ma10, ma20)
      data_list.append(datas)
      t += 1
    return data_list, t

class CandlestickItem(pg.GraphicsObject):
  def __init__(self, data):
    pg.GraphicsObject.__init__(self)
    self.data = data
    self.generatePicture()

  def generatePicture(self):
    self.picture = QtGui.QPicture()
    p = QtGui.QPainter(self.picture)
    p.setPen(pg.mkPen('w'))
    w = (self.data[1][0] - self.data[0][0]) / 3.
    prema5 = 0
    prema10 = 0
    prema20 = 0
    for (t, open, close, min, max, volume, price_change, p_change, ma5, ma10, ma20) in self.data:
      if open > close:
        p.setPen(pg.mkPen('g'))
        p.setBrush(pg.mkBrush('g'))
      else:
        p.setPen(pg.mkPen('r'))
        p.setBrush(pg.mkBrush('r'))
      p.drawLine(QtCore.QPointF(t, min), QtCore.QPointF(t, max))
      p.drawRect(QtCore.QRectF(t - w, open, w * 2, close - open))
      if prema5 != 0:
        p.setPen(pg.mkPen('w'))
        p.setBrush(pg.mkBrush('w'))
        p.drawLine(QtCore.QPointF(t-1, prema5), QtCore.QPointF(t, ma5))
      prema5 = ma5
      if prema10 != 0:
        p.setPen(pg.mkPen('c'))
        p.setBrush(pg.mkBrush('c'))
        p.drawLine(QtCore.QPointF(t-1, prema10), QtCore.QPointF(t, ma10))
      prema10 = ma10
      if prema20 != 0:
        p.setPen(pg.mkPen('m'))
        p.setBrush(pg.mkBrush('m'))
        p.drawLine(QtCore.QPointF(t-1, prema20), QtCore.QPointF(t, ma20))
      prema20 = ma20
    p.end()

  def paint(self, p, *args):
    p.drawPicture(0, 0, self.picture)

  def boundingRect(self):
    return QtCore.QRectF(self.picture.boundingRect())

if __name__ == "__main__":
  import sys
  app = QtGui.QApplication(sys.argv)
  MainWindow = QtGui.QMainWindow()
  ui = Ui_MainWindow()
  ui.setupUi(MainWindow)
  MainWindow.show()
  sys.exit(app.exec_())

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