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delavg

Headings-> Description Example

Delete Average from Matrix Columns

Syntax	y = delavg(x)
Include:	include spt\delavg.oms
See Also


ARGUMENTS:
   INPUTS:  
      x = MATRIX, representing input data, any numerical type,
   RETURN: MATRIX, input with column averages deleted.

Description

Subtracts the average value of each column of a matrix from the respective column. This is equivalent to removing the DC component in each column vector of the input.
Input data is a matrix of any numerical type. Return ttype is always type DOUBLE. Input is coerced to DOUBLE before local processing. The special case of a row vector input is treated as a column vector with row vector return. This function will return 0(zero) for SCALAR input.

Example

Create one cycle of a sinewave. Then add a DC offset to it. Lastly, remove the offset with the delavg() function.

O>x = sin(2*PI*seq(16)/16)
O>y = x + 1.55
O>z = delavg(y)
O>colmean(x)
-0.00000 
O>colmean(y)
 1.55000 
O>colmean(z)
 0.00000