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Conference rusure::math

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

462.0. "Impressions from Maple" by KBOV05::J_WOLFF (Julian Wolff) Wed Mar 26 1986 08:24

    Here some other impressions to MAPLE I found out. 
    Perhaps anyone can help or noticed the same things:
    
    1. Maple seems not to 'shorten' (excuse me if not the correct word)
       the expressions. I integrate the following: (x^2 + y^2)^(1/2)
       and as Maple provided the answer I differentiate it and the result
       was a very long expression ... but correct. So is there a function
       I do not know which performs this type of operation.
    
    2. Is there any way to ask Maple which variables are in use at the
       moment - think of 5 different functions you have and you want
       to print them at the terminal, to see what you already have !?
    
    3. I am unable to use the 'map' function to differentiate the following
       vector:
    			     x sin(x)
    			h = 
			     cos(x)

       It simply says plse use map function to diff tables/arrays and
       map (in no format) accepts h. Can someone tell me what is wrong.

    4. The input procedure for big matrices is complicated ans costs
       time but this is just my opinion. Sometimes a screen formatted
       input especial for matrices will be a big improve.
    
    5. The integral function does not integrate things which seem to
       be quite simple like 1/sin(x). And there is no description what
       type of integrals it can solve the only thing it says is:
       'A big variety of integrals'.
    
    6. Can I order the reference manual at the University of waterloo
       can perhaps Lynn provide me with the address.
    
    
    	Julian.
T.RTitleUserPersonal
Name		DateLines
462.1More...KBOV07::J_WOLFFJulian WolffWed Mar 26 1986 11:1818
    A short correction to 5.:
    
      It does integrate 1/Sin(x) but it does not (1/ln(cos(x))).
    
    And...
    
    7. If you do a recall of the previous command MAPLE puts an extra
       LF in instead of staying on the line.
    
    
    Overall impression:
    
    	---- Very good program. ---
    
    
    	Julian.
462.2How to order MAPLE manualMETOO::YARBROUGHWed Mar 26 1986 17:105
    The MAPLE USER'S GUIDE can be ordered ($19.80 US) from:
    	WATCOM Publications Ltd.
        415 Phillip St.
    	Waterloo, Ontario
    	N2L 3X2
462.3some helpMETOO::YARBROUGHWed Mar 26 1986 17:1615
    re .1: The following functions can be used to transform an expression
    into a possibly more convenient form:
    	normal()
    	collect()
    	convert/...
    	expand()
    	factor()
    	radsimp()
    	simpl...
    
    The list of currently assigned names is given by 
    	anames();
    This includes the names of 'loaded' procedures as well as variable
    names. By the way, the 'value' of an otherwise unassigned name is
    its own name.
462.4After all, it's free...METOO::YARBROUGHWed Mar 26 1986 17:347
    I don't know what your expectations are, but int(ln(cos(u))) is
    distinctly NOT simple. Gradsteyn and Ryzhik only gives it in the
    form int(...,0,x) for which the value is -L(x), Lobachevski's function
    which is an infinite series of complicated terms. I'll be willing
    to leave that as an exercise for the reader...   I wasn't able to
    locate the integral of 1/ln(cos(u)) at all, although maybe it's
    simpler.
462.5Ok, right.KBOV05::J_WOLFFJulian WolffWed Mar 26 1986 18:2121
    re .4:
    
    Right Lynn, it is not that simple as I seem to see it, when you are
    reading my note. It might wrong expressed.
    
    I just want t try how strong Maple is at integrating functions
    that is normally more complicated then to differentiate.
    
    It just came in my mind because in one test at university I (we)
    had to solve such a thing and no success at that time and I wonder
    if maple would be able.
    
    My expectations are not too high but I want to use it as an tool
    which works with correct results - and it does this.

    
	Julian.
    
    PS thanks for the info in .2 and .3
462.6Maple$Lib Correct definitions.KBOV05::J_WOLFFJulian WolffFri Mar 28 1986 20:2222
    I fixed the problem with the logical Maple$Lib.
    
    If you define Maple$Lib in the following way you may run Maple from
    other devices as well as from the installed one.
    
    Wrong Definition:
    
    	$ Define/System Maple$Lib Maple$Disk:[Maple.Lib]
    Maple cannot see (or does not want to see) the device Maple$Disk
    
    Correct Definition:
    
        $ Define/System Maple$Lib "Maple$Disk:[Maple.Lib]"
    Now it can see the device and works wonderful.
    
    (I think the supplied startup procedure is not correct here and
     must be modified.)
    
    
    	Julian.