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Latency of FIR filter

returns the latency, `Y`

= getLatency(`hdlfir`

,`inputType`

,[],`isInputComplex`

)`Y`

, between the first valid input sample
and the first valid output sample, assuming contiguous input samples. The latency
depends on filter structure and filter coefficients. Use this syntax when you are
not using programmable coefficients. The final three arguments may be optional,
depending on the object configuration.

Use

`inputType`

when you set`CoefficientsDataType`

property to`'Same word length as input'`

. The latency can change with input data type because the object casts the coefficients to the input data type, which can affect multiplier sharing for equal-absolute-value coefficients.Use

`isInputComplex`

when your input data is complex and you are using a partly-serial systolic architecture. The latency changes when you have complex data and complex coefficients because of the extra adder pipeline. When you specify`isInputComplex`

, you must also give a placeholder argument,`[]`

for the unused third argument.

returns the latency, `Y`

= getLatency(`hdlfir`

,`coeffType`

,`coeffPrototype`

,`isInputComplex`

)`Y`

, between the first valid input sample
and the first valid output sample, assuming contiguous input samples. The latency
depends on filter structure and filter coefficients. Use this syntax when you are
using programmable coefficients. `coeffType`

is the data type of
the input coefficients. The final two arguments may be optional, depending on the
object configuration.

Use

`coeffPrototype`

to optimize the programmable filter for symmetric or antisymmetric coefficients. The prototype specifies a pattern that all input coefficients must follow. Based on the prototype, the object implements an optimized filter that shares the multipliers for symmetric coefficients. If your input coefficients do not all conform to the same pattern, or to opt out of multiplier optimization, you can omit this argument or specify the prototype as an empty vector,`[]`

.Use

`isInputComplex`

when your input data is complex. When you specify`isInputComplex`

, you must also specify the`coeffPrototype`

or a placeholder argument,`[]`

.