import logging


def approx_methods() -> list[str]:
    """Available laplace approximation types."""
    try:
        return [ 'beltrami', 'cotangens', 'mesh', 'fem' ]
    except ImportError:
        logging.warn(
            "fem appxoimation only works if lapy is installed. "
            "You can find lapy on github: https://github.com/Deep-MI/LaPy.\n"
            "Install it with pip:\n"
             "pip3 install --user git+https://github.com/Deep-MI/LaPy.git#egg=lapy")
        return [ 'beltrami', 'contangens', 'mesh' ]