Pylab与随机属性

Question

你好吗？我想编写程序，但它给我的属性错误。我是python的新手，我会很感激你的帮助。 导入pylab，随机

def rSquare(measured, estimated):
    diffs = (estimated - measured)**2
    mMean = measured.sum()/float(len(measured))
    var = (mMean - measured)**2
    return 1 - diffs.sum()/var.num()

numPts = 7
points = ()
xVals = pylab.arange(numPts)
for x in xVals: points.append(x + random.random())
points = pylab.array(points)
pylab.scatter(xVals, points)
a1,b1 = pylab.polyfit(xVals, points, 1)
estVals1 = a1*xVals + b1

print 'Linear fit to points:', rSquare(points, estVals1)
pylab.plot(xVals, estVals1, c = 'b')
a,b,c,d,e,f = pylab.polyfit(xVals, points, 5)
estVals5 = a*(xVals**5) + b*(xVals**4) + c*(xVals**3) + d*(xVals**2) + \
          e*xVals + f


print '5th order fit to same points:', rSquare(points, estVals5)
pylab.plot(xVals, estVals5, c = 'r')

pylab.show()

请检查错误

Traceback (most recent call last):
Documents\python files\squaremean.py", line 12, in <module>
for x in xVals: points.append(x + random.random())
AttributeError: 'tuple' object has no attribute 'append'

Answer 1

元组是不可变的。使用列表：

points = []
xVals = pylab.arange(numPts)
for x in xVals: points.append(x + random.random())

或每次创建一个新元组：

for x in xVals: points = points + (x + random.random(),)

或者只创建一次整个元组：

points = tuple(x + random.random() for x in xVals)

或者直接使用numpy：

points = xVals + np.random.random(len(xVals))