Asymmetric Least Squares Baseline correction

The AsLS function applies Asymmetric Least Squares (AsLS) to correct baselines in spectral data or similar signals. This method iteratively adjusts weights for positive and negative residuals, enabling it to suppress baseline components without distorting peaks. The smoothing parameter (lambda) controls the baseline's smoothness, with larger values resulting in smoother baselines, while the asymmetry parameter (p) determines the emphasis on negative residuals to retain signal features.