[Tutor] getting error while solving a series that estimates the value of pi

[surya k]

Hi,

The problem is to estimate the value of pi using the following series.
 *1 / pi  = (( 2 * sqrt(2) )/ 9801 )  * SIGMA of k[ (4k)! (1103 + 26390*k) /
(k!^ 4 ) * 396^(4k)  ]*
*where k is [0, infinity)*
* Problem is located at : ThinkPython Book, www.thinkpython.org
   *Pg 89, Exercise 7.5, Think Python Book. *
*
*
the series should be considered till the last term of the sigma must be <
1e-15
I have written the below code :

*# program estimates the value of pi*
*# Ramanujan's series... *
*import math*
*
*
*def fact(n) : # def of factorial function.*
*    if n > 0 :    *
*       return n * fact(n-1)*
*    if n == 0 :*
*       return 1*
*
*
*k = 0*
*tot = 0*
*temp1 = 0*
*while k >= 0 and temp1 == 0 :*
*
*
*      a = ( 2 * math.sqrt(2) ) / 9801 # first term before sigma *
*      nu = fact (4*k) * (1103 + (26390*k) )  # numerator of series*
*      de = pow( fact(k), 4 ) * pow ( 396, 4*k )  # denominator of series*
*      *
*      if de / nu > 1e-15 : *
*            temp = nu / de*
*            tot = tot + temp*
*            temp1 = 0 *
*            k = k + 1 *
*      elif de / nu  == 1e-15 :*
*             series = a * tot  *
*             k = k + 1*
*             temp1 = 0*
*      elif de / nu < 1e-15 :*
*             print series*
*             temp1 = 1*


I am getting the following error : which is completely surprising!

*Traceback (most recent call last):*
*  File "pi.py", line 30, in <module>*
*    print series*
*NameError: name 'series' is not defined*

*
*
Thus I have removed name 'series' and replaced with  *a*tot, *
now I am getting this error

*Traceback (most recent call last):*
*  File "pi.py", line 30, in <module>*
*    print 1 / (a * tot)*
*ZeroDivisionError: float divisio*n



Thus I changed the first highlighted lines to

 *nu = float (fact (4*k) * (1103 + (26390*k) ) )*
*      de = float (pow( fact(k), 4 ) * pow ( 396, 4*k )) *


now I am getting

* Traceback (most recent call last):*
*  File "pi.py", line 18, in <module>*
*    de = float (pow( fact(k), 4 ) * pow ( 396, 4*k ) )*
*OverflowError: long int too large to convert to float*

*help me out of this problem, how could I fix this*
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