J1
Description
This function returns the first order Bessel function:
J1(x)
The formula for the equation is:
/math-d89d9d5b3f053ecef1ec8648817ba97c.png "J_1(x)=\sum_{k=0}^{\infty} \frac{(-1)^{k}(x/2)^{2k+1}}{k!\Gamma(k+2)}")
See the gammaln(x) function for the definition of /math-07710b5c43702a8bb7b9104eacc6ba71.png "\Gamma")
.
Syntax
double J1(double x)
Parameter
x
- is the double at which you want to calculate the first order Bessel function.
Return
Returns the first order Bessel function at x.
Example
aa = j1(5); aa =; //-0.32757913759147