[comp.sys.hp] Complex Variables with HP-28S

jlong@afit-ab.arpa (Jeffrey K. Long) (11/21/88)

Does anyone know how to use a complex variable in the sover or plot
routines?  I would like to do something like the following:
    plot y=exp(mag(x))   {where 'x' is a complex variable in x}
  (this is not a real problem, just the basic idea)


I tried two posts to comp.sys.handhelds but got no replies or posts.
I really can't belive that there isn't a way to do this, but 6 of my fellow
EE-graduate students here at the Air Force Institute of Technology own these
wonderful calculators and we all have the same question.  Anyone who has done
work in electromagnetics or antenna theory can appreciate our need for this!


A
A

jlong@afit-ab.arpa (Jeffrey K. Long) (11/22/88)

In article <741@afit-ab.arpa>  I wrote:
>Does anyone know how to use a complex variable in the sover or plot
>routines?  I would like to do something like the following:
>    plot y=exp(mag(x))   {where 'x' is a complex variable in x}
>  (this is not a real problem, just the basic idea)

I guess I didn't make myself clear about what I meant by complex
variable, so maybe this example will make it clearer:
        
         plot exp(abs((x,3)))

akhiani@s.cs.uiuc.edu (11/23/88)

			Complex Function Plot Using HP-28 

	y=exp(Mag (1/(1+s)))    where s is  (jw)  EE notation or
                 			  (0+i*w) HP notation
        So in order to plot this function we plot:
		'EXP(ABS(P))'
        where P is      
		'INV(1+i*w)'
	or any other complex function.
	The point is you have to use  (a+i*b) notation not (a,b) 

	I hope this is the answer to your questions. 
	I plot frequency response using this method on my HP-28C 
	and it is satisfactory. But it is a little bit slower.
	
-Homayoon Akhiani
 University of Illinois
 Urbana/Champaign

akhiani@s.cs.uiuc.edu (11/24/88)

	Use     'EXP(ABS(x+i*3))'
	
	(x,3) is same as (x+i*3)