Window-based FIR filter design

`fir1`

uses a least-squares approximation to
compute the filter coefficients and then smooths the impulse response
with `window`

.

[1] Digital Signal Processing Committee of the
IEEE Acoustics, Speech, and Signal Processing Society, eds. *Programs
for Digital Signal Processing*. New York: IEEE Press, 1979,
Algorithm 5.2.

`cfirpm`

| `designfilt`

| `filter`

| `fir2`

| `fircls`

| `fircls1`

| `firls`

| `firpm`

| `freqz`

| `hamming`

| `kaiserord`