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NI-DSP Analysis VI Reference 
Chapter 2
Part 3:  NI-DSP Function Reference 2-7 NI-DSP SRM for LabVIEW for Windows
DSP Blackman Window
Applies a Blackman window to the input
sequence X.  If Y represents the output
sequence Blackman{X}, the elements of Y
are obtained from the following formula:
y
i
  =  x
i
 [0.42 - 0.50 cos(w)
+ 0.08 cos(2w)]
for  i = 0, 1, 2, … , n-1 ,
w  =  
2
π
i
n
 ,
where n is the number of elements in X.
X is a DSP Handle Cluster that indicates the memory buffer on the DSP board that contains the input
signal array.
Note: The operation is performed in place and the input array is overwritten by the output
Blackman {X}.
Blackman {X} is a DSP Handle Cluster that is identical to X, but with the results of Blackman {X}
already stored in the memory buffer on the DSP board.
error in (no error) contains the error information from a previous VI.  If an error occurs, it is passed out
error out and no other calls are made.
error out contains the error information for this call.