def in_domain(self, xs, ys, x):
        # Disable black-list functions: filter used for speed instead of
        # list-comprehension
        # pylint: disable-msg=W0141
        def isInDomain(xy):
            """Used for filter to check if point is in the domain"""
            u = (xy[0]-x)/self.h
            return u >= self.domain[0] and u <= self.domain[1]

        if self.domain is None:
            return (xs, ys)
        else:
            filtered = lfilter(isInDomain, lzip(xs, ys))
            if len(filtered) > 0:
                xs, ys = lzip(*filtered)
                return (xs, ys)
            else:
                return ([], [])
take two arrays of values and return the initial values
dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/sandbox/nonparametric/kernels.py/CustomKernel.in_domain--crossover with--dataset/ETHPy150Open CGATOxford/cgat/CGAT/Counts.py/means2idxarrays