如何在Python中重新创建调用TREND()的Excel公式?
我想用Python重新创建Excel的趋势函数,找到了C#答案()。使用这个,我用Python重新创建了。我想我会发布它,以防对其他人有用 Python实现:如何在Python中重新创建调用TREND()的Excel公式?,python,Python,我想用Python重新创建Excel的趋势函数,找到了C#答案()。使用这个,我用Python重新创建了。我想我会发布它,以防对其他人有用 Python实现: def LeastSquaresValueAtX(points, knownX, xBar, x): ''' Gets the value at a given x using the line of best fit (least square method) to determine the e
def LeastSquaresValueAtX(points, knownX, xBar, x):
'''
Gets the value at a given x using the line of best fit
(least square method) to determine the equation
'''
slope = SlopeOfPoints(points, knownX, xBar)
yIntercept = YInterceptOfPoints(points, xBar, slope)
return (slope * x) + yIntercept
def SlopeOfPoints(points, knownX, xBar):
'''
Gets the slope for a set of points using the formula:
m=sum(x-avg(x)(y-avg(y))/sum(x-avg(x))**2
'''
yBar=dividend=divisor=0.0
for i in points:
yBar=yBar+i
yBar=yBar/5
for j in points:
kx = knownX.pop()
dividend+=((kx-xBar)*(j-yBar))
divisor+=((kx-xBar)**2)
return dividend / divisor
def YInterceptOfPoints(points, xBar, slope):
'''
Gets the y-intercept for a set of points using the formula:
b-avg(y)-m(avg(x))
'''
yBar =0.0
for i in points:
yBar=yBar+i
yBar=yBar/5
return yBar - (slope * xBar)
def test(knownX, t):
if t==1: return LeastSquaresValueAtX([4,13,10,22,20],[2011,2010,2009,2008,2007],2009,2012)
if t==2: return LeastSquaresValueAtX([7,20,26,29,23],knownX, 2009,2012)
if t==3: return LeastSquaresValueAtX([6,5,4,3,7], knownX, 2009,2012)
print test([2011,2010,2009,2008,2007], 1)##26.1
print test([2011,2010,2009,2008,2007], 2)##33.3
print test([2011,2010,2009,2008,2007], 3)##5.0
我认为C#标记是不必要的。