I am getting wrong answer for factorial(22)
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I keep getting 1.1198e+21 for factorial(22) but in the xample problem on matlab the answer is 1.24000728E21.
Problem
a1 = factorial(22)
b = (sqrt(2*pi*22))*(22^22/exp(22))
c = (abs((a1 - b)/a1))*100
Outputs
a1 = 1.1198e+21
b = 1.1198e+21
c = 0
0 Comments
Answers (1)
James Tursa
on 15 Jan 2020
R2016a PCWIN64:
>> a1 = factorial(22)
a1 =
1.124000727777608e+21
>> b = (sqrt(2*pi*22))*(22^22/exp(22))
b =
1.119751494628234e+21
>> c = (abs((a1 - b)/a1))*100
c =
0.378045409078625
What version of MATLAB are you running? Are you shadowing the MATLAB factorial( ) function with one of your own? I.e., what does this reply:
which factorial
2 Comments
Steven Lord
on 15 Jan 2020
If the problem recurs, run the last line of code in James Tursa's answer and check that you're calling the factorial function included in MATLAB. Actually, I'd suggest a slight modification to James's code:
which -all factorial
The factorial.m in the toolbox\matlab\specfun directory is the factorial function included in MATLAB so it's OK. Any factorial.m files listed in the output of the above command whose entry ends with "<some class name> method" are OK as well. If you see other factorial.m files you may want to rename or remove them.
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