# Apodization.m

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Performs free induction decay apodization. Supports 1D, 2D and 3D FIDs with the following syntax:

fid=apodization(fid,window_type,params)

Arguments:

fid - The free induction decay. The function expects a column vector in the case of 1D FID, a 2D matrix with the time origin located at the (1,1) corner point in the case of a 2D FID, and a 3D matrix with the time origin located at the (1,1,1) corner point in the case of a 3D FID.

window_type - Type of the window function. The following window func- tion types are supported:

'none-1d' divides the first point by 2 and does noth- ing else.

'crisp-1d' divides the first point by 2 and multiplies the FID by a matched cos^8 half-bell.

'exp-1d' divides the first point by 2 and multiplies the FID by a decaying exponential with the decay rate specified by the user.

'gaussian-1d' divides the first point by 2 and multiplies the FID by a decaying Gaussian with the de- cay rate specified by the user.

'cosbell-1d' divides the first point by 2 and multiplies the FID by a matched cosine half-bell.

'echo-1d' multiplies the FID by sine square bell, used for DEER spin echoes.

'kaiser-1d' divides the first point by 2 and multiplies the FID by a Kaiser function with the decay rate specified by the user.

'hamming-1d' divides the first point by 2 and multiplies the FID by a matched Hamming function.

'none-2d' divides the corner point by 2 and does noth- ing else.

'crisp-2d' divides the corner point by 2 and multipli- es the FID by a matched cos^4 half-bell.

'exp-2d' divides the corner point by 2 and multipli- es the FID by a decaying exponential in both dimensions with the decay rate specified by the user.

'gaussian-2d' divides the corner point by 2 and multipli- the FID by a decaying Gaussian in both dim- ensions with the decay rate specified by the user.

'cosbell-2d' divides the corner point by 2 and multipli- es the FID by a matched cosine half-bell in both dimensions.

'sqcosbell-2d' divides the first point by 2 and multiplies the FID by matched squared cosine half-bell.

'echo-2d' multiplies one dimension by the square sine bell, used for DEER echo processing.

'cosbell-3d' divides the corner point by 2 and multipli- es the FID by a matched cosine half-bell in all three dimensions.

params - decay rate parameters for those window functions that require such parameters. If a function does not requi- re a parameter, the value of params is ignored. Defa- value of params is zero.