def AdjustValue(self, vardict):
        """
        Adjust the value of a constant parameter. This is useful for something like
        setting the pressure or the telescope zenith distance, which will be known very
        well and is important to getting a good fit, but does not need to be varied.

        Warning: The variable will be removed from the list of variables to fit, so
        DO NOT use this to adjust the value of a parameter you want TelFit to adjust!

        :param vardict: a dictionary where the key is the parameter
                        name and the value is the value of that parameter.
                        Valid parameter names can be found by invoking
                        DisplayVariables(fitonly=False)

        :return: None
        """
        for par in vardict.keys():
            try:
                idx = self.parnames.index(par)
                if par in ['wavestart', 'waveend'] and isinstance(vardict[par], u.quantity.Quantity):
                    # Convert to nanometers
                    vardict[par] = vardict[par].to(u.nm).value
                self.const_pars[idx] = vardict[par]
                self.fitting[idx] = False
            except __HOLE__:
                print("Error! Bad parameter name given. Currently available are: ")
                self.DisplayVariables()
                raise ValueError


            ### -----------------------------------------------
dataset/ETHPy150Open kgullikson88/Telluric-Fitter/src/TelluricFitter.py/TelluricFitter.AdjustValue