| Title: | Mathematics at DEC | 
| Moderator: | RUSURE::EDP | 
| Created: | Mon Feb 03 1986 | 
| Last Modified: | Fri Jun 06 1997 | 
| Last Successful Update: | Fri Jun 06 1997 | 
| Number of topics: | 2083 | 
| Total number of notes: | 14613 | 
	     In my effort to learn LISP on my own, I managed to develop 
	a program that will compute the reduced simplicial homology for any 
	given finite simplicial complex.  The program resides at:
	hpstek::newprod:[xia.ai.fast.homology]homology.fas
	To run this program, simply get into the LISP interpreter.
	First load the program, i.e.
	Lisp> (load "homology.fas") <return>
	Then do:
	Lisp> (homology "[filename]") <return>
	where the filename is the name of the file that contains the 
	relevant simplicial complex.  The program will return a list
	of objects each is the reduced homological group of proper order.
	There are three examples in the same directory:
	TORUS.DAT, KLEIN_BOTTLE.DAT and PROJECTIVE_PLANE
	The format for those files are self-explanatory.  The only 
	constrain is that the vertex names must be alphanumerical,
	i.e. they must all begin with an alphabet.
	-------------------------------------------------------------
	Example: 
	$ lisp
	Lisp> (load "homology.fas") <return>
	T
	Lisp> (homology "klein_bottle.dat") <return>
	((0) ((Z 0) (Z 2)) (0))
	Lisp> 
	-------------------------------------------------------------
                                            ~      ~
	The return of the program says that H = 0, H = Z + Z/2
                                             0      1
	    ~
	and H = 0.
             2
	Eugene
| T.R | Title | User | Personal Name | Date | Lines | 
|---|---|---|---|---|---|
| 1215.1 | Stupid question: What is homology? | GENRAL::HEINTZE | Tue Apr 10 1990 11:24 | 3 | |
|     What is homology and what is it good for?
    
    					Sieg
 | |||||
| 1215.2 | The only stupid question is the one not asked | ELIS::BUREMA | Elen s�la lumenn omentilmo | Mon Jun 17 1991 06:48 | 4 | 
|     
    What is homology and what is it good for?
    
    					Wildrik
 | |||||
| 1215.3 | Look here tomorrow | AGOUTL::BELDIN | Pull us together, not apart | Mon Jun 17 1991 16:02 | 3 | 
|     I should know, but I'll have to look it up tonite!
    
    Dick
 | |||||
| 1215.4 | VINO::XIA | In my beginning is my end. | Mon Jun 24 1991 15:52 | 6 | |
|     re .3,
    
    I think, by now, you have realized the reason why no one has answered
    the question yet.  :-)
    
    Eugene
 | |||||
| 1215.5 | Aha... | ELIS::BUREMA | Elen s�la lumenn omentilmo | Tue Jun 25 1991 07:27 | 7 | 
|     Re: .4, .0
    
    Could it have anything to do with the tomorrow of the date the base
    note was entered...
    
    Wildrik 8-}
    
 | |||||