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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



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

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Introduced before R2006a