hanning

Hanning windowing function.

Syntax

hanning(vec_expr)

Argument

vec_expr
A valid vector expression.

Example

Curve Math Vectors Result
x = c1.x

y = fftmag(hanning(c1.y))

Given c1, a curve is created which is the original curve windowed using the Hanning window function.

Comments

The resultant vector is vec_expr multiplied by the Hanning window function. This function is given by:

(1)

where w is the windowing function and N is the number of elements of vec_expr. Windowing functions are normally used in conjunction with frequency operations. A Hanning window function is shown below.



Figure 1.

The resulting curve is power-normalized, in other words, the root mean square (RMS) of the original curve equals the RMS of the resulting curve. The mean is subtracted from the input before windowing in order to eliminate DC bias.