'float' / 'int' object is not iterable

[python101]

I try to calculate the sum of an infinite series
S = Sum (from n=0 to 100) 1/k!
I got message 'float' / 'int' object is not iterable. How can I fix this?

[bartonc]

I try to calculate the sum of an infinite series
S = Sum (from n=0 to 100) 1/k!
I got message 'float' / 'int' object is not iterable. How can I fix this?

Hmmm... I've never seen syntax like that before.. The capital "S" in "Sum" should have thrown the first error in pure Python. ...Then there is the lack of CODE tags in your post..

[CODE=python]
>>> sum(range(100))
4950
>>> 99*50
4950
>>>
>>> sum(range(100))/1000
4
>>> sum(range(100))/1000.0
4.9500000000000 002
>>> [/CODE]

[bartonc]

I try to calculate the sum of an infinite series
S = Sum (from n=0 to 100) 1/k!
I got message 'float' / 'int' object is not iterable. How can I fix this?

Infinite, huh? There's got to be some limit:[CODE=python]
>>> sum(xrange(2**1 6))
2147450880
>>> sum(xrange(2**3 2))
File "<console>" , line 1, in ?
''' exceptions.Over flowError : long int too large to convert to int '''
>>> [/CODE]

[python101]

Infinite, huh? There's got to be some limit:[CODE=python]
>>> sum(xrange(2**1 6))
2147450880
>>> sum(xrange(2**3 2))
File "<console>" , line 1, in ?
''' exceptions.Over flowError : long int too large to convert to int '''
>>> [/CODE]

yes, that why I limited k to 100

[python101]

Hmmm... I've never seen syntax like that before.. The capital "S" in "Sum" should have thrown the first error in pure Python. ...Then there is the lack of CODE tags in your post..

[CODE=python]
>>> sum(range(100))
4950
>>> 99*50
4950
>>>
>>> sum(range(100))/1000
4
>>> sum(range(100))/1000.0
4.9500000000000 002
>>> [/CODE]

it was not the code, only the problem because I could not type the mathematical symbol so I used Sum

[bartonc]

yes, that why I limited k to 100

Now every one knows... I'm more of a mechanic than a mathematician.

[python101]

here is what I want to calculate by using Python

[KaezarRex]

here is what I want to calculate by using Python

This method comes up with the answer 2.71828182846. Is that right?
[CODE=python]def factorial(n):
if n < 1:
return 1
else:
return n * factorial(n-1)

def summation(k, limit):
if k == limit:
return 1.0/factorial(k)
else:
return 1.0/ factorial(k) + summation(k+1, limit)

print summation(0, 100)[/CODE]

[bvdet]

here is what I want to calculate by using Python

Does this work for you?[code=Python]def factorial(n):
if n == 0:
return 1
else:
return n*factorial(n-1)

def calc(k, u):
return float(sum(range (u+1)))/factorial(k)[/code]

>>> calc(4, 100)
210.41666666666 666
>>>

[python101]

This method comes up with the answer 2.71828182846. Is that right?
[CODE=python]def factorial(n):
if n < 1:
return 1
else:
return n * factorial(n-1)

def summation(k, limit):
if k == limit:
return 1.0/factorial(k)
else:
return 1.0/ factorial(k) + summation(k+1, limit)

print summation(0, 100)[/CODE]

yes, it is e - thank you very much

[python101]

Anyway, do we have another way (like using for loop) to approach this problem?

[kdt]

Anyway, do we have another way (like using for loop) to approach this problem?

If you want to avoid the use of recursion you can use the following. The factorial is calculated using a while loop, and the summation by a for loop. :

[CODE=python]

>>> def factorial(n):
f=1
while(n>0):
f*=n # same as f=f*n, just faster
n-=1# same as n=n-1
return f

>>> def summation(k, limit):
sigma=0
for i in range(k, limit+1): # +1 added to catch both k=0 and k=100
sigma+=(1.0/factorial(i))
return sigma

>>> summation(0, 100)
2.7182818284590 455

[/CODE]

HTH

[bvdet]

Now I understand the calculation you are after. Here is another version using a list comprehension:[code=Python]>>> def calc(k, u):
... return sum([1.0/factorial(i) for i in range(k, u+1)])
...
>>> calc(0, 100)
2.7182818284590 455
>>> [/code]

[python101]

Now I understand the calculation you are after. Here is another version using a list comprehension:[code=Python]>>> def calc(k, u):
... return sum([1.0/factorial(i) for i in range(k, u+1)])
...
>>> calc(0, 100)
2.7182818284590 455
>>> [/code]

I tried code but it did not return any value.

[bvdet]

I tried code but it did not return any value.

I tried it again:[code=Python]>>> def calc(k, u):
... return sum([1.0/factorial(i) for i in range(k, u+1)])
...
>>> x = calc(50, 60)
>>> x
3.3536826466330 641e-065
>>> [/code]What do you think is wrong with the code?