I want to calculate factorial of a large data set containing some NaN in between the data.

example : data set

7

8

95

210

85

NaN

NaN

52

NaN

Answer 1

[Guillaume]

I would assume you want an output the same size as the input, in which case:

V = [7     8    95   210    85   NaN   NaN    52   NaN]'  %demo data

result = nan(size(v));
result(~isnan(v)) = factorial(v(~isnan(v)))

As documented factorial is only exact for input less than or equal to 21. factorial([95, 85, 52]) gives you an inaccurate result but with the correct order of magnitude. factorial(210) is far beyound what can be stored as double precision. Anything above factorial(171) is too big.

[Abhijeet Kumar]

Thanks sir. It works.

Answer 2

[madhan ravi]

a=[7
8
95
210
85
NaN
NaN
52
NaN]

factorial(a(~isnan(a))) % why not this?

[Abhijeet Kumar]

sir your answer is correct but it is ignoring the NaN values in final answer and reducing the data size form 9 to 6.

[madhan ravi]

Ah now i know what you want , cheers :)