In mathematics, the gamma function is an extension of the factorial function, with its argument shifted down by 1, to real and complex numbers.
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Value (mathematics)
In mathematics, value commonly refers to the output of a function. In the most basic case, that of unary, single-valued functions, there is one input and one output (the value of the function). A real-valued function is a function that associates to every element of the domain a real number in the image. Example: If the function is defined by prescribing that for each real number, then the input 3 will yield the function value 10 (since indeed {{{1}}}).
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Subroutine
In computer science, a subroutine, also termed procedure, function, routine, method, or subprogram, is a part of source code within a larger computer program that performs a specific task and is relatively independent of the remaining code. As the name subprogram suggests, a subroutine behaves in much the same way as a computer program that is used as one step in a larger program or another subprogram.
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Bessel function
In mathematics, Bessel functions, first defined by the mathematician Daniel Bernoulli and generalized by Friedrich Bessel, are canonical solutions y(x) of Bessel's differential equation: for an arbitrary real or complex number ¿ (the order of the Bessel function); the most common and important cases are for ¿ an integer or half-integer. Although ¿ and ¿¿ produce the same differential equation, it is conventional to define different Bessel functions for these two orders (e.g.
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