def on(self, analyte=None, filt=None):
        """
        Turn on specified filter(s) for specified analyte(s).

        Parameters
        ----------
        analyte : optional, str or array_like
            Name or list of names of analytes.
            Defaults to all analytes.
        filt : optional. int, str or array_like
            Name/number or iterable names/numbers of filters.

        Returns
        -------
        None
        """
        if isinstance(analyte, str):
            analyte = [analyte]
        if isinstance(filt, (int, float)):
            filt = [filt]
        elif isinstance(filt, str):
            filt = self.fuzzmatch(filt, multi=True)

        if analyte is None:
            analyte = self.analytes
        if filt is None:
            filt = list(self.index.values())

        for a in analyte:
            for f in filt:
                if isinstance(f, (int, float)):
                    f = self.index[int(f)]

                try:
                    self.switches[a][f] = True
                except KeyError:
                    f = self.fuzzmatch(f, multi=False)
                    self.switches[a][f] = True

                # for k in self.switches[a].keys():
                #     if f in k:
                #         self.switches[a][k] = True
        return
Turn on specified filter(s) for specified analyte(s).

        Parameters
        ----------
        analyte : optional, str or array_like
            Name or list of names of analytes.
            Defaults to all analytes.
        filt : optional. int, str or array_like
            Name/number or iterable names/numbers of filters.

        Returns
        -------
        None