forked from TheAlgorithms/Python
- Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathsimpson_rule.py
More file actions
Latest commit
86 lines (70 loc) · 2.19 KB
/
Copy pathsimpson_rule.py
File metadata and controls
86 lines (70 loc) · 2.19 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
"""
Numerical integration or quadrature for a smooth function f with known values at x_i
This method is the classical approach of summing 'Equally Spaced Abscissas'
method 2:
"Simpson Rule"
"""
defmethod_2(boundary: list[int], steps: int) ->float:
# "Simpson Rule"
# int(f) = delta_x/2 * (b-a)/3*(f1 + 4f2 + 2f_3 + ... + fn)
"""
Calculate the definite integral of a function using Simpson's Rule.
:param boundary: A list containing the lower and upper bounds of integration.
:param steps: The number of steps or resolution for the integration.
:return: The approximate integral value.
>>> round(method_2([0, 2, 4], 10), 10)
2.6666666667
>>> round(method_2([2, 0], 10), 10)
-0.2666666667
>>> round(method_2([-2, -1], 10), 10)
2.172
>>> round(method_2([0, 1], 10), 10)
0.3333333333
>>> round(method_2([0, 2], 10), 10)
2.6666666667
>>> round(method_2([0, 2], 100), 10)
2.5621226667
>>> round(method_2([0, 1], 1000), 10)
0.3320026653
>>> round(method_2([0, 2], 0), 10)
Traceback (most recent call last):
...
ZeroDivisionError: Number of steps must be greater than zero
>>> round(method_2([0, 2], -10), 10)
Traceback (most recent call last):
...
ZeroDivisionError: Number of steps must be greater than zero
"""
ifsteps<=0:
raiseZeroDivisionError("Number of steps must be greater than zero")
h= (boundary[1] -boundary[0]) /steps
a=boundary[0]
b=boundary[1]
x_i=make_points(a, b, h)
y=0.0
y+= (h/3.0) *f(a)
cnt=2
foriinx_i:
y+= (h/3) * (4-2* (cnt%2)) *f(i)
cnt+=1
y+= (h/3.0) *f(b)
returny
defmake_points(a, b, h):
x=a+h
whilex< (b-h):
yieldx
x=x+h
deff(x): # enter your function here
y= (x-0) * (x-0)
returny
defmain():
a=0.0# Lower bound of integration
b=1.0# Upper bound of integration
steps=10.0# number of steps or resolution
boundary= [a, b] # boundary of integration
y=method_2(boundary, steps)
print(f"y = {y}")
if__name__=="__main__":
importdoctest
doctest.testmod()
main()