Hinweis：Dieser Abschnitt ist nur in englischer Sprache verfügbar. Wir bitten um Ihr Verständnis.
3.5.1.3.27 Cos_integral
Definition:
\(Ci=cos\_integral(x)\) evaluates
- \[C_i\left( x\right) =y+\ln x+\int_0^x\frac{\cos u-1}udu\]
- \[C_i\left( x\right) =y+\ln x+\int_0^x\frac{\cos u-1}udu\]
where \(\gamma\) denotes Euler's constant. The approximation is based on several Chebyshev expansions.
For more information please review the s13acc function in the NAG document.
Parameters:
- x (input, double)
- The argument x of the function.
- Constraint: x>0.0
- \(Ci\) (output, double)
- The approximation of the formula \(C_i\left( x\right) =y+\ln x+\int_0^x\frac{\cos u-1}udu\),x>0