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NI-DSP Analysis VI Reference 
Chapter 2
Part 3:  NI-DSP Function Reference 
2-30
NI-DSP SRM for LabVIEW for Windows
DSP Exact Blackman Window
Applies an Exact Blackman window to
the input sequence X.  If Y represents
the output sequence Exact
Blackman{X}
, the elements of Y are
obtained using the formula:
y
i
  =  x
i
 [0.42659071
- 0.49656062 cos(w)
+ 0.07684867 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 X  is overwritten by the output Exact
Blackman {X}.
Exact Blackman {X} is a DSP Handle Cluster that is identical to X, but with the results of Exact
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.