Returns the physical units of the argument.
        
        
            Arguments
        
        
            
                
                
                
                
                
                
                    
                        | 
                            
                                Number
                            
                         | 
                        
                            
                                Type
                            
                         | 
                        
                            
                                Compulsory
                            
                         | 
                        
                            
                                Default
                            
                         | 
                        
                            
                                Description
                            
                         | 
                    
                    
                        | 
                            1
                         | 
                        
                            any
                         | 
                        
                            Yes
                         | 
                        
                         | 
                        
                            vector or vector name
                         | 
                    
                
            
        
        
            Returns
        
        
            Return type: string
        
        
            Possible return values are:
        
        
            - 
                " (meaning dimensionless)
            
 
            - 
                '?' (meaning unknown)
            
 
            - 
                'V'
            
 
            - 
                'A'
            
 
            - 
                's'
            
 
            - 
                'Hz'
            
 
            - 
                'Ohm'
            
 
            - 
                'S'
            
 
            - 
                'F'
            
 
            - 
                'H'
            
 
            - 
                'J'
            
 
            - 
                'W'
            
 
            - 
                'C'
            
 
            - 
                'Vs'
            
 
            - 
                'V???MATH???^2???MATH???'
            
 
            - 
                'V???MATH???^2???MATH???/Hz'
            
 
            - 
                'V/rtHz'
            
 
            - 
                'A???MATH???^2???MATH???'
            
 
            - 
                'A???MATH???^2???MATH???/Hz'
            
 
            - 
                'A/rtHz'
            
 
            - 
                'V/s'
            
 
        
        
        
        
            See Also