Raymond Toy (RT/EUS | 7 Feb 16:06 2008
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Re: numerical evaluation of psi0

Barton Willis wrote:
> I evaluated psi[0](1.78095) using  webMathematica, Maple 10, and Maxima
> 5.14.0 to 50
> digits:
> 
> Created by webMathematica
> 0.27085244394958037219241274879122247322668078991599
> Maple
> 0.27085617938915025987352993092362827661833339343790
> Maxima
> 0.2708561793891502598735299309236282766183333934379b-1
> 
> (1) What's the story?

You mean that Mma returns something different?  I think you need to say 
1.780950000<lots more zeroes>0.  Something about how mma does some kind 
of significance arithmetic or something.  I get something close to 
Maple's value then.

> 
> (2) Does anybody have a reference to how our psi function works? It
> seems to use a modified asymptotic expansion.

I looked at bffac a while back that is the asymptotic series for log 
gamma.  A peek at bfpsi shows that it is probably also the asymptotic 
series for psi.  Probably A&S 6.3.18.

(We should document these routines.)
> 
> (3) Does our psi function work in the complex plane? --- you do need
(Continue reading)

Barton Willis | 7 Feb 16:43 2008

Re: numerical evaluation of psi0


maxima-bounces <at> math.utexas.edu wrote on 02/07/2008 09:06:39 AM:

> Barton Willis wrote:
> > I evaluated psi[0](1.78095) using  webMathematica, Maple 10, and Maxima
> > 5.14.0 to 50

> You mean that Mma returns something different?  

When I re-did the Mma calculation, all three values agreed. Sorry about that.

> > (2) Does anybody have a reference to how our psi function works? It
> > seems to use a modified asymptotic expansion.

> I looked at bffac a while back that is the asymptotic series for log
> gamma.  A peek at bfpsi shows that it is probably also the asymptotic
> series for psi.  Probably A&S 6.3.18.

I think there is a clever modification of 6.3.18. If I figure it out, I'll
append a comment. Let's see if we can tweak bfpsi0 to work better in the
complex plane...

Barton
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Jelle de Jong | 7 Feb 22:06 2008
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request for help getting maxima to plot the like i would want

Hello everybody,

I have been using and developing linux for 3 years and am an experienced
user. I am following some basic mathematical classes on my university.
In this collage I have to use software to calculate and analyze
functions. The software that is used is called Derive:
http://en.wikipedia.org/wiki/Derive_computer_algebra_system

For a real FLOSS user this is not an option, so I went trying out all
the mathematical tools for GNU/Linux. I think maxima is the program that
should be able to do all the calculations and visualisations on the
functions I use. However after spending a day working and trying I cant
get my functions to plot the way I want and to calculate on them
(differentiations / Integration / Compare / Solve).

I tried to do somethings but its not working out very well.

Would somebody be willing to help me out, and demonstrate the command
required to be able to plot in almost exactly the same way as the 2
example pages with the plots, that I included as attachment. (see this 
link: http://filebin.ca/jggfuw)

Kind regards,

Jelle

Formulas and things i was working on:

f(z):=-x-y+5;
f(z):=9-x^2-Y^2;
f(z):=5-x^2;

f(z):=-2*x-y+4;
f(z):=-x-3*y+6;
f(z):=x+y-4;

f(z):=x^2+y^2=r^2;
r:3;

f(z0):=0=y-x^2;
f(z1):=1=y-x^2;
f(z4):=4=y-x^2;

solve(f(z0));

f(z):=5-x^2;
plot2d(f(z),[x,-6,6],[y,-6,6],[xlabel,"X"],[ylabel,"Y"],[gnuplot_preamble,"set 

xzeroaxis;set yzeroaxis;unset border;set xtics"]);

plot3d(f(z),[x,-6,6],[y,-6,6]);
Jelle de Jong | 7 Feb 22:08 2008
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request for help getting maxima to plot the like i would want (correct link)

Hello everybody,

I have been using and developing linux for 3 years and am an experienced
user. I am following some basic mathematical classes on my university.
In this collage I have to use software to calculate and analyze
functions. The software that is used is called Derive:
http://en.wikipedia.org/wiki/Derive_computer_algebra_system

For a real FLOSS user this is not an option, so I went trying out all
the mathematical tools for GNU/Linux. I think maxima is the program that
should be able to do all the calculations and visualisations on the
functions I use. However after spending a day working and trying I cant
get my functions to plot the way I want and to calculate on them
(differentiations / Integration / Compare / Solve).

I tried to do somethings but its not working out very well.

Would somebody be willing to help me out, and demonstrate the command
required to be able to plot in almost exactly the same way as the 2
example pages with the plots, that I included as attachment. (see this
link: http://filebin.ca/fzqyn) (djvu file)

Kind regards,

Jelle

Formulas and things i was working on:

f(z):=-x-y+5;
f(z):=9-x^2-Y^2;
f(z):=5-x^2;

f(z):=-2*x-y+4;
f(z):=-x-3*y+6;
f(z):=x+y-4;

f(z):=x^2+y^2=r^2;
r:3;

f(z0):=0=y-x^2;
f(z1):=1=y-x^2;
f(z4):=4=y-x^2;

solve(f(z0));

f(z):=5-x^2;
plot2d(f(z),[x,-6,6],[y,-6,6],[xlabel,"X"],[ylabel,"Y"],[gnuplot_preamble,"set 

xzeroaxis;set yzeroaxis;unset border;set xtics"]);

plot3d(f(z),[x,-6,6],[y,-6,6]);
Mario Rodriguez | 7 Feb 23:29 2008
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Re: request for help getting maxima to plot the like i would want

Jelle de Jong escribió:
> Hello everybody,
>
> I have been using and developing linux for 3 years and am an experienced
> user. I am following some basic mathematical classes on my university.
> In this collage I have to use software to calculate and analyze
> functions. The software that is used is called Derive:
> http://en.wikipedia.org/wiki/Derive_computer_algebra_system
>
> For a real FLOSS user this is not an option, so I went trying out all
> the mathematical tools for GNU/Linux. I think maxima is the program that
> should be able to do all the calculations and visualisations on the
> functions I use. However after spending a day working and trying I cant
> get my functions to plot the way I want and to calculate on them
> (differentiations / Integration / Compare / Solve).
>
> I tried to do somethings but its not working out very well.
>
> Would somebody be willing to help me out, and demonstrate the command
> required to be able to plot in almost exactly the same way as the 2
> example pages with the plots, that I included as attachment. (see this 
> link: http://filebin.ca/jggfuw)
>   

Hello,

You can try this code with Maxima 5.14:

load(draw)$

draw3d(implicit(z=-x-y+5, x,0,5, y,0,5, z,0,5))$

draw3d(surface_hide = true,
       implicit(z=9-x^2-y^2, x,-4,4, y,-4,4, z,0,10))$

/*
Define the parametric curve:
x=t,
y=2,
z=5-t^2
*/
draw3d(parametric(t,2,5-t^2, t,-5,5))$

type ? draw for more information about this package.

--

-- 
Mario Rodriguez Riotorto
www.biomates.net
Jelle de Jong | 7 Feb 22:04 2008
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request for help getting maxima to plot the like i would want

Hello everybody,

I have been using and developing linux for 3 years and am an experienced 
user. I am following some basic mathematical classes on my university. 
In this collage I have to use software to calculate and analyze 
functions. The software that is used is called Derive:
http://en.wikipedia.org/wiki/Derive_computer_algebra_system

For a real FLOSS user this is not an option, so I went trying out all 
the mathematical tools for GNU/Linux. I think maxima is the program that 
should be able to do all the calculations and visualisations on the 
functions I use. However after spending a day working and trying I cant 
get my functions to plot the way I want and to calculate on them 
(differentiations / Integration / Compare / Solve).

I tried to do somethings but its not working out very well.

Would somebody be willing to help me out, and demonstrate the command 
required to be able to plot in almost exactly the same way as the 2 
example pages with the plots, that I included as attachment.

Kind regards,

Jelle

Formulas and things i was working on:

f(z):=-x-y+5;
f(z):=9-x^2-Y^2;
f(z):=5-x^2;

f(z):=-2*x-y+4;
f(z):=-x-3*y+6;
f(z):=x+y-4;

f(z):=x^2+y^2=r^2;
r:3;

f(z0):=0=y-x^2;
f(z1):=1=y-x^2;
f(z4):=4=y-x^2;

solve(f(z0));

f(z):=5-x^2;
plot2d(f(z),[x,-6,6],[y,-6,6],[xlabel,"X"],[ylabel,"Y"],[gnuplot_preamble,"set 
xzeroaxis;set yzeroaxis;unset border;set xtics"]);

plot3d(f(z),[x,-6,6],[y,-6,6]);
_______________________________________________
Maxima mailing list
Maxima <at> math.utexas.edu
http://www.math.utexas.edu/mailman/listinfo/maxima
Jelle de Jong | 8 Feb 13:30 2008
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Re: request for help getting maxima to plot the like i would want

Mario Rodriguez wrote:
> Jelle de Jong escribió:
>> Hello everybody,
>>
>> I have been using and developing linux for 3 years and am an experienced
>> user. I am following some basic mathematical classes on my university.
>> In this collage I have to use software to calculate and analyze
>> functions. The software that is used is called Derive:
>> http://en.wikipedia.org/wiki/Derive_computer_algebra_system
>>
>> For a real FLOSS user this is not an option, so I went trying out all
>> the mathematical tools for GNU/Linux. I think maxima is the program that
>> should be able to do all the calculations and visualisations on the
>> functions I use. However after spending a day working and trying I cant
>> get my functions to plot the way I want and to calculate on them
>> (differentiations / Integration / Compare / Solve).
>>
>> I tried to do somethings but its not working out very well.
>>
>> Would somebody be willing to help me out, and demonstrate the command
>> required to be able to plot in almost exactly the same way as the 2
>> example pages with the plots, that I included as attachment. (see this 
>> link: http://filebin.ca/jggfuw)
>>   
> 
> Hello,
> 
> You can try this code with Maxima 5.14:
>
> load(draw)$
> 
> draw3d(implicit(z=-x-y+5, x,0,5, y,0,5, z,0,5))$
> 
> draw3d(surface_hide = true,
>       implicit(z=9-x^2-y^2, x,-4,4, y,-4,4, z,0,10))$
> 
> /*
> Define the parametric curve:
> x=t,
> y=2,
> z=5-t^2
> */
> draw3d(parametric(t,2,5-t^2, t,-5,5))$
> 
> type ? draw for more information about this package.
> 

Hi Mario,

Thank you for your help, I compiled the latest maxima and have been 
trying your command:

However I am still unable to get an X-ax and Y-Ax in the middle:

      Y
      |
      |
----------- X
      |
      |

I have been trying the following input, however I cant get it right.

I got a function that I substitute with an other function creating a new 
function that I want to plot. I think I really need a good document with 
  examples how to port math that you do with your hands and head to 
something I can enter in maxima.

function: z=y-x^2;
function, z=4;
solve(%,y);
plot2d(%,[x,-10,10]);

load("draw");
f1: 4;
f2: y-x^2;
solve(f1=f2,y);
draw2d(explicit(%,x,-6,6));

Kind regards,

Jelle
Helge Hansen | 8 Feb 16:20 2008
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Problem with "globalsolve:true"


Hi,

Does anybody understand why K2 in the following script is not solved global?
What am I doing wrong? In my opinion the last line should be:
M(z)=z*A-(q*z^2)/2

(%i1) M(z)::=K2+A*z-q*z^2/2;
(%o1) M(z)::=K2+A*z+((-q)*z^2)/2

(%i2) globalsolve:true$

(%i3) solve([M(z)=0,z=0],[K2,z]);
(%o3) [[K2=0,z=0]]

(%i4) display(M(z))$

M(z)=K2+z*A-(q*z^2)/2
Mario Rodriguez | 8 Feb 16:28 2008
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Re: request for help getting maxima to plot the like i would want

Hello,

> Hi Mario,
>
> Thank you for your help, I compiled the latest maxima and have been 
> trying your command:
>
> However I am still unable to get an X-ax and Y-Ax in the middle:
>
>       Y
>       |
>       |
> ----------- X
>       |
>       |
>
> I have been trying the following input, however I cant get it right.
>   

This is an (baroque) example showing options related to axis in 3d (you 
probably won't need to use all of them!):

draw3d(
       xaxis=true, xaxis_color = red, xaxis_type=solid, xaxis_width=2,
       yaxis=true, yaxis_color = aquamarine, yaxis_type=solid, 
yaxis_width=4,
       zaxis=true, zaxis_color = "#ff25cb", zaxis_type=dots, zaxis_width=6,
       xrange = [-1,6], yrange = [-1,6], zrange = [-1,6],
       xlabel = "Athos", ylabel = "Portos", zlabel = "Aramis",
       user_preamble= "set xyplane at 0",
       implicit(z=-x-y+5, x,0,5, y,0,5, z,0,5));

> load("draw");
> f1: 4;
> f2: y-x^2;
> solve(f1=f2,y);
> draw2d(explicit(%,x,-6,6));
>   
Note in this example that %[1] is the 1st component of the list returned 
by solve, which is an equation, and rhs returns its right hand side:

f1: 4;
f2: y-x^2;
solve(f1=f2,y);
draw2d(explicit(rhs(%[1]),x,-6,6));

hth

--

-- 
Mario Rodriguez Riotorto
www.biomates.net
R Fateman | 8 Feb 16:50 2008
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Re: Problem with "globalsolve:true"

globalsolve does not redefine functions.  You seem to be using much more 
complicated syntax and ideas than needed. Also you should use linsolve 
if you want to have globalsolve work. Solve on systems apparently 
ignores globalsolve, perhaps because algebraic systems may have many 
solutions... which should be assigned globally>

Try

M:  K2+A*z-q*z^2/2;
globalsolve:true;

linsolve([M=0,z=0],[K2,z]);

ev(M);

or just substituting z=0 in Helge Hansen wrote:
> Hi,
>
> Does anybody understand why K2 in the following script is not solved global?
> What am I doing wrong? In my opinion the last line should be:
> M(z)=z*A-(q*z^2)/2
>
> (%i1) M(z)::=K2+A*z-q*z^2/2;
> (%o1) M(z)::=K2+A*z+((-q)*z^2)/2
>
> (%i2) globalsolve:true$
>
> (%i3) solve([M(z)=0,z=0],[K2,z]);
> (%o3) [[K2=0,z=0]]
>
> (%i4) display(M(z))$
>
> M(z)=K2+z*A-(q*z^2)/2
>
>
>  
> _______________________________________________
> Maxima mailing list
> Maxima <at> math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima
>   

Gmane