def x(self, x):
        """Project x"""
        if x is None or x <= 0 or self.log10_xmax - self.log10_xmin == 0:
            return None
        return (
            self.width * (log10(x) - self.log10_xmin) /
            (self.log10_xmax - self.log10_xmin)
        )
Project x