Functions |
| struct iir_coeff_t * | iir_coeff_new (int nc, const double *c, int nd, const double *d) |
| | Create IIR coefficient set.
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| struct iir_coeff_t * | iir_coeff_copy (const struct iir_coeff_t *other) |
| | Create copy of a set of IIR coefficients.
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| void | iir_coeff_free (struct iir_coeff_t *coeff) |
| | Free IIR coefficient set.
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| int | iir_coeff_get_nc (const struct iir_coeff_t *coeff) |
| | Query number of C coefficients.
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| int | iir_coeff_get_nd (const struct iir_coeff_t *coeff) |
| | Query number of D coefficients.
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| double | iir_coeff_get_c (const struct iir_coeff_t *coeff, int idx) |
| | Get value of C coefficient.
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| double | iir_coeff_get_d (const struct iir_coeff_t *coeff, int idx) |
| | Get value of D coefficient.
|
Detailed Description
The functions in this module present an interface for managing the set of coefficients of a single IIR filter instance. See Structure of IIR filter for the definition of a coefficient set. The coefficient sets form the basic building block of an IIR filter instance (see Basic IIR filtering), which may chain several IIR filters in sequence.
Function Documentation
| struct iir_coeff_t* iir_coeff_new |
( |
int |
nc, |
|
|
const double * |
c, |
|
|
int |
nd, |
|
|
const double * |
d |
|
) |
| |
|
read |
Create IIR coefficient set.
- Parameters
-
| nc | Number of c coefficients. |
| c | Array of c coefficients. |
| nd | Number of d coefficients. |
| d | Array of d coefficients. |
- Returns
- Pointer to new general IIR filter object.
This function creates a new set of IIR filter coefficients which may be used to create filter instances through iir_filter_new() or chained on to existing instances through iir_filter().
See Structure of IIR filter for a full explanation of the parameters.
| struct iir_coeff_t* iir_coeff_copy |
( |
const struct iir_coeff_t * |
other | ) |
|
|
read |
Create copy of a set of IIR coefficients.
- Parameters
-
| other | Set of IIR filter coefficients to copy. |
- Returns
- Pointer to new general IIR filter object.
Performs a deep copy of the set of IIR coefficients contained within other.
| void iir_coeff_free |
( |
struct iir_coeff_t * |
coeff | ) |
|
Free IIR coefficient set.
- Parameters
-
| coeff | Pointer to IIR coefficient object. May be 0. |
Frees a set of IIR filter coefficients previously allocated through iir_coeff_new(). Can be called on a null pointer without consequences. Note that iir_filter_new() and iir_filter_chain() actually store a copy of the coefficients, so it is possible to free coeff even if existing filters are still using its coefficient values.
| int iir_coeff_get_nc |
( |
const struct iir_coeff_t * |
coeff | ) |
|
Query number of C coefficients.
- Parameters
-
| coeff | Pointer to IIR coefficient object. |
- Returns
- Number of C coefficients (≥1).
| int iir_coeff_get_nd |
( |
const struct iir_coeff_t * |
coeff | ) |
|
Query number of D coefficients.
- Parameters
-
| coeff | Pointer to IIR coefficient object. |
- Returns
- Number of D coefficients (≥1).
| double iir_coeff_get_c |
( |
const struct iir_coeff_t * |
coeff, |
|
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int |
idx |
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) |
| |
Get value of C coefficient.
- Parameters
-
| coeff | Pointer to IIR coefficient object. |
| idx | Index of coefficient (≥0, < iir_coeff_get_nc()). |
- Returns
- C coefficient value.
| double iir_coeff_get_d |
( |
const struct iir_coeff_t * |
coeff, |
|
|
int |
idx |
|
) |
| |
Get value of D coefficient.
- Parameters
-
| coeff | Pointer to IIR coefficient object. |
| idx | Index of coefficient (≥0, < iir_coeff_get_nd()). |
- Returns
- D coefficient value.
