Python如何绘制K线图？

这是py中的案例

"""
Demonstrate creation of a custom graphic (a candlestick plot)

"""
# import initExample ## Add path to library (just for examples; you do not need this)

import py as pg
from py import QtCore, QtGui

## Create a subclass of GraphicsObject.
## The only required methods are paint() and boundingRect()
## (see documentation)
class CandlestickItem(pg.GraphicsObject):
def __init__(self, data):
pg.GraphicsObject.__init__(self)
self.data = data ## data must have fields: time, open, close, min, max
self.generatePicture()

def generatePicture(self):
## pre-computing a object allows paint() to run much more ,
## rather than re-drawing the shapes every time.
self.picture = QtGui.()
p = QtGui.(self.picture)
p.setPen(pg.mkPen('w'))
w = (self.data[1][0] - self.data[0][0]) / 3.
print('w is:',w)
for (t, open, close, min, max) in self.data:
p.drawLine(QtCore.(t, min), QtCore.(t, max))
if open > close:
p.setBrush(pg.mkBrush('r'))
else:
p.setBrush(pg.mkBrush('g'))
p.drawRect(QtCore.QRectF(t - w, open, w * 2, close - open))
p.end()

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

def boundingRect(self):
## boundingRect _must_ indicate the entire area that will be drawn on
## or else we will get artifacts and possibly crashing.
## (in this case, does all the work of computing the bouning rect for us)
return QtCore.QRectF(self.picture.boundingRect())

data = [ ## fields are (time, open, close, min, max).
(1., 10, 13, 5, 15),
(2., 13, 17, 9, 20),
(3., 17, 14, 11, 23),
(4., 14, 15, 5, 19),
(5., 15, 9, 8, 22),
(6., 9, 15, 8, 16),
]
item = CandlestickItem(data)
plt = pg.plot()
plt.addItem(item)
plt.setWindowTitle('py example: customGraphicsItem')

## Start Qt event loop unless running in interactive mode or using pyside.
if __name__ == '__main__':
import sys

if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui..instance().exec_()