Parks–McClellan filter design algorithm

The Parks-McClellan algorithm, also known as the Remez exchange algorithm, is a widely used method for designing linear-phase finite impulse response (FIR) digital filters. It is particularly effective in designing filters with specified frequency response characteristics, such as low-pass, high-pass, band-pass, and band-stop filters. The algorithm minimizes the maximum error between the desired response and the actual response of the filter.