def fwhm2sigma(fwhm):
fwhm = np.asarray(fwhm)<EOL>return fwhm / np.sqrt(<NUM_LIT:8> * np.log(<NUM_LIT:2>))<EOL>
Convert a FWHM value to sigma in a Gaussian kernel.

    Parameters
    ----------
    fwhm: float or numpy.array
       fwhm value or values

    Returns
    -------
    fwhm: float or numpy.array
       sigma values