iframe-proxy | Sunbelt Computer Software

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import math

def bisection(

function, a, b

): # finds where the function becomes 0 in [a,b] using bolzano

start = a

end = b

if function(a) == 0: # one of the a or b is a root for the function

return a

elif function(b) == 0:

return b

elif (

function(a) * function(b) > 0

): # if none of these are root and they are both positive or negative,

# then his algorithm can't find the root

print("couldn't find root in [a,b]")

return

else:

mid = start + (end - start) / 2.0

while abs(start - mid) > 10 ** -7: # until we achieve precise equals to 10^-7

if function(mid) == 0:

return mid

elif function(mid) * function(start) < 0:

end = mid

else:

start = mid

mid = start + (end - start) / 2.0

return mid

def f(x):

return math.pow(x, 3) - 2 * x - 5

if __name__ == "__main__":

print(bisection(f, 1, 1000))

Sunbelt Computer Software