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Coefficients for filters


s = coeffs(ha)
s = coeffs(hd)
s = coeffs(hs)
s = coeffs(hs,Name,Value)


s = coeffs(ha) returns a structure containing the coefficients of the adaptive filter ha.

s = coeffs(hd) returns a structure containing the coefficients of the discrete-time filter hd.

s = coeffs(hs) returns filter coefficients for the filter System object™ hs.

s = coeffs(hs,Name,Value) returns filter coefficients for the filter System object hs with additional options specified by one or more Name,Value pair arguments.

Input Arguments

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Discrete-time dfilt filter object.


Filter System object.

The following Filter System objects are supported by this analysis function:

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside single quotes (' '). You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

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For filter System object inputs only, specify the arithmetic used during analysis. When you specify 'double' or 'single', the function performs double- or single-precision analysis. When you specify 'fixed' , the arithmetic changes depending on the setting of the CoefficientDataType property and whether the System object is locked or unlocked.

 Details for Fixed-Point Arithmetic

When you do not specify the arithmetic, the function uses double-precision arithmetic if the filter System object is in an unlocked state. If the System object is locked, the function performs analysis based on the locked input data type.

Output Arguments


Structure with a single field, Numerator, containing filter coefficients. For adaptive filters, s contains the instantaneous frequency response available at the time you use the function.


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FIRHalfbandInterp = dsp.FIRHalfbandInterpolator('Specification',...
    'Filter order and transition width','FilterOrder',26);
C = coeffs(FIRHalfbandInterp);

% Impulse response of the filter
ans =

  Columns 1 through 7

    0.0525         0   -0.0379         0    0.0537         0   -0.0771

  Columns 8 through 14

         0    0.1172         0   -0.2060         0    0.6345    1.0000

  Columns 15 through 21

    0.6345         0   -0.2060         0    0.1172         0   -0.0771

  Columns 22 through 27

         0    0.0537         0   -0.0379         0    0.0525

Introduced in R2011a

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