我一直在爲我的項目做Python編程,並且我剛剛開始。這可能是另一個微不足道的問題。我有這個代碼,我需要使用在函數poly_root()中計算的值,它是x。該值應該用作bezier()函數中的u。在poly_root()函數之後,它應該使用它的計算值進入bezier()函數。我不知道我是否以正確的方式進行。沒有錯誤,但它不會從bezier()函數中打印出來。非常感謝你。將從一個函數計算出的值傳遞給另一個函數
import copy
import math
poly = [[-0.8,3], [0.75,2], [-0.75,1], [0.1,0]]
def poly_diff(poly):
""" Differentiate a polynomial. """
newlist = copy.deepcopy(poly)
for term in newlist:
term[0] *= term[1]
term[1] -= 1
return newlist
def poly_apply(poly, x):
""" Apply values to the polynomial. """
sum = 0.0 # force float
for term in poly:
sum += term[0] * (x ** term[1])
return sum
def poly_root(poly, start, n, r_i):
""" Returns a root of the polynomial, with a starting value."""
poly_d = poly_diff(poly)
x = start # starting guess value
counter = 0
while True:
if (n >= 0) and (n < 1):
break
x_n = x - (float(poly_apply(poly, x))/poly_apply(poly_d, x))
if x_n == x:
break
x = x_n # this is the u value corresponding to the given time which will be used in bezier equation
n -= 1
counter += 1
if r_i:
#print [x, counter])
return [x, counter]
else:
#print x
return x
bezier(x)
def bezier(value) :
""" Calculates control points using rational bezier curve equation"""
u = value
w = 5
t = math.pow(1-u,3) * points[0][0] + 3 * u * math.pow(1-u,2) * points[1][0] \
+ 3 * (1-u) * math.pow(u,2) * points[2][0] + math.pow(u,3) * points[3][0]
t = t * w
d = math.pow(1-u,3) * w + 3 * u * w * math.pow(1-u,2) + 3 * (1-u) * w \
* math.pow(u,2) + math.pow(u,3) * w
t = t/d
print t
if __name__ == "__main__" :
poly_root(poly, 0.42, 1, 0)
我明白了。當然,我在想什麼。現在它正常運行。謝謝。 – zingy