# besselj¶

## Purpose¶

Computes a Bessel function of the first kind, $$J_n(x)$$.

## Format¶

y = besselj(n, x)
Parameters:
• n (NxK matrix or P-dimensional array where the last two dimensions are NxK) – The order of the Bessel function. Non-integers will be truncated to an integer.

• x (LxM matrix or P-dimensional array) – where the last two dimensions are LxM, ExE conformable with n

Returns:

y (max(N,L) by max(K,M) matrix or P-dimensional array) – array where the last two dimensions are max(N, L) by max(K, M)

## Examples¶

// Create the sequence 0.1, 0.2, 0.3,...,19.9
x = seqa(0, 0.1, 200);

// Calculate a first order Bessel function
n = 1;
y0 = besselj(n, x);

// Calculate the first and second order Bessel function
n = { 1 2 };
y = besselj(n, x);

/*
** Plot the output of the first and second order Bessel
** functions
*/
plotXY(x, y);


In the code above, the calculation of both the first and second order Bessel functions assigns the return from the first order calculation to be the first column of y and the return from the calculation of the second order function to be the second column of y.

The plotXY() function treats each incoming column as a separate line.