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NI-DSP Analysis VI Reference 
Chapter 2
Part 3:  NI-DSP Function Reference 
2-34
NI-DSP SRM for LabVIEW for Windows
DSP Force Window
Applies a force window to the input sequence X
If Y represents the output sequence Force{X},
the elements of  Y are obtained using the
formula:
y
i
  = 
 

x
i
 
   if  0 
 i 
  d
 
0   
 
elsewhere
for  i = 0, 1, 2, …, n-1 ,
d  =  (0.01)(n)(duty)
where n is the number of elements in X.
You can use the Force Window VI to analyze transients.
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
Force {X}.
duty.  0.0 
 duty 
 100.0.  duty defaults to 50.0.
Force {X} is a DSP Handle Cluster that is identical to X, but with the results of Force {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.
DSP Free Memory
Frees the memory space referred by DSP
Handle Cluster
 on the specified DSP board.
DSP Handle Cluster is a DSP Handle Cluster that indicates the memory buffer to free.
error in (no error) contains the error information from a previous VI.  If an error occurs, it is passed out
error out and the VI also frees the DSP Handle Cluster.
error out contains the error information for this call.