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Exponential integral


Y = expint(X)


Y = expint(X) evaluates the exponential integral for each element of X.

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Exponential Integral

The exponential integral computed by this function is defined as

E1(x)=xet/t dt

Another common definition of the exponential integral function is the Cauchy principal value integral

Ei(x)=xet/t dt

which, for real positive x, is related to expint as


Tall Array Support

This function fully supports tall arrays. For more information, see Tall Arrays.


[1] Abramowitz, M. and I. A. Stegun. Handbook of Mathematical Functions. Chapter 5, New York: Dover Publications, 1965.

Introduced before R2006a

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