new_swdft_cosreg: Constructor function for class swdft_mod
In swdft: Sliding Window Discrete Fourier Transform (SWDFT)

Constructor function for class swdft_mod

1	new_swdft_cosreg(coefficients, fitted, residuals, data)

`coefficients`	matrix of coefficients for cosine regression model
`fitted`	fitted values of cosine regression model
`residuals`	residuals of cosine regression model
`data`	original signal used to fit cosine regression

list with the following elements

coefficients. A matrix of parameters, the three columns are: 1. amplitude 2. phase, and 3. frequency. There is only more that one row used when multiple frequencies are fit sequentially.
fitted. fitted values of cosine regression model
residuals. residuals of cosine regression model
data. original signal used to fit cosine regression