CxElp_BPF
Advanced Analysis Library Only
AnalysisLibErrType CxElp_BPF (NIComplexNumber inputArray[], ssize_t numberOfElements, double samplingFrequency, double lowerCutoffFreq, double upperCutoffFreq, double rippledb, double stopBandAttendb, int order, NIComplexNumber outputArray[]);
Purpose
Filters the complex input array using an elliptic bandpass digital filter. CxElp_BPF can perform the operation in place; that is, the input and output arrays can be the same.
Example Code
/* Generate a random signal and filter it using a fifth-order bandpass elliptic filter. The pass band is from 200.0 to 300.0. */
NIComplexNumber x[256];
double input[256];
double fs, fl, fh, ripple, atten;
ssize_t n;
int order;
int status;
int i;
n = 256;
fs = 1000.0;
fl = 200.0;
fh = 300.0;
order = 5;
ripple = 0.2;
atten = 60.0;
WhiteNoise (n, 1, 17, input);
for(i = 0; i < n; i++){
x[i].real = input[i];
x[i].imaginary = input[i];
}
status = CxElp_BPF (x, n, fs, fl, fh, ripple, atten, order, NULL);
Parameters
| Input | ||
| Name | Type | Description |
| inputArray | NIComplexNumber [] | Array containing the raw data to filter. |
| numberOfElements | ssize_t | Number of elements in both the input and output array. |
| samplingFrequency | double | The frequency in Hertz at which you want to sample inputArray. This value must be greater than 0. |
| lowerCutoffFreq | double | Lower cutoff frequency in Hertz. This value must be 0 < lowerCutoffFreq < upperCutoffFreq < 0.5 * samplingFrequency. |
| upperCutoffFreq | double | Upper cutoff frequency in Hertz. This value must be 0 < lowerCutoffFreq < upperCutoffFreq < 0.5 * samplingFrequency. |
| ripple_db | double | The amplitude of the stop band ripple in decibels. This value must be greater than 0. Default Value: 0.1 db. |
| stopBandAtten_db | double | Stop band attenuation in decibels. This value must be greater than 0. Default Value: 40.0 db. |
| order | int | Filter order. This value must be greater than 0. Default Value: 5. |
| Output | ||
| Name | Type | Description |
| outputArray | NIComplexNumber [] | Filtered data. |
Return Value
| Name | Type | Description |
| status | AnalysisLibErrType | A value that specifies the type of error that occurred. Refer to analysis.h for definitions of these constants. |
Additional Information
Library: Advanced Analysis Library
Include file: analysis.h
LabWindows/CVI compatibility: LabWindows/CVI 2012 and later