def graphic_slider(self, nb_case):
        """
        This function scales the slider for curves displayed.
        Input : The number of cases (curves).
        Return ; The slider value.
        """

        """
        The slider range is created each time we call this function. Search to set its range just when it is necessary.
        """

        self.ui.sens.setDisabled(False)
        self.ui.sens.setRange(0, int(nb_case - 1))
        self.slider_value = self.ui.sens.value()

        return self.slider_value
This function scales the slider for curves displayed.
        Input : The number of cases (curves).
        Return ; The slider value.