ButterPZ: Calculate Butterworth Filter Poles and Zeros
In TDD: Time-Domain Deconvolution of Seismometer Response

Description Usage Arguments Details Value Author(s) Examples

Calculates continuous poles and zeros (of the Laplace transform) of Butterworth filters.

1	ButterPZ(fl = NaN, nl = NaN, fh = NaN, nh = NaN, g = 1)

`fl`	Low corner frequency (Hz)
`nl`	Order of high-pass filter
`fh`	High corner frequency (Hz)
`nh`	Order of low-pass filter
`g`	gain (unitless)

For a bandpass filter, all inputs should be non-NaN. For high pass, fh and nh should be NaN; for low pass, fl and nl should be NaN. Input corner frequencies are in cycles/second, not radians/second.

List including the following elements:

`poles`	Vector of poles (rad/s)
`zeros`	Vector of zeros (rad/s)
`np`	Number of poles
`nz`	Number of zeros
`Knorm`	Normalization constant
`Sense`	Sensitivity (V * s/m)

Jake Anderson

1
2
3

# Calculate poles and zeros of Butterworth filter with a second-order
# high-pass above 1 Hz, and a fourth-order low-pass below 10 Hz
ButterPZ(1, 2, 10, 4)

Loading required package: signal

Attaching package: 'signal'

The following objects are masked from 'package:stats':

    filter, poly

Loading required package: RSEIS
Loading required package: pracma

Attaching package: 'pracma'

The following objects are masked from 'package:RSEIS':

    detrend, hypot, logspace, peaks, trapz

The following objects are masked from 'package:signal':

    conv, ifft, interp1, pchip, polyval, roots


Attaching package: 'TDD'

The following object is masked from 'package:RSEIS':

    ReadInstr

$Sense
[1] 1

$Knorm
[1] 15585455-0i

$poles
[1]  -4.442883+ 4.442883i  -4.442883- 4.442883i -24.044709+58.049063i
[4] -58.049063+24.044709i -58.049063-24.044709i -24.044709-58.049063i

$np
[1] 6

$zeros
[1] 0 0

$nz
[1] 2