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janhardo

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11 years, 47 days
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@Rouben Rostamian   Thanks This m...

janhardo 700
July 25 2020
0 0

@Rouben Rostamian  

Thanks

This must be the calculated answer  : 76 + 2/25 for the green area

Its not done in 5 minutes this vectorcalculations  

 

 

@Rouben Rostamian Thanks  The ra...

janhardo 700
July 25 2020
0 0

@Rouben Rostamian

Thanks 

The ratio is 25/144  ~ 1/6 , the calculated answer is : 76 + 2/25 for the green area.
2 by 4 gives 8 is area => x 6  green area  : about 48
So this ratio is not working then. 

@Carl Love Interesting but complica...

janhardo 700
July 25 2020
0 0

@Carl Love 

Interesting but complicated to follow, what  solutions strategy is followed ?
I do see a implicit differentation and put from this together 3 linear equations 

 

@Carl Love  Thanks The derivation ...

janhardo 700
July 24 2020
0 0

@Carl Love 
Thanks

The derivation by  hand was correct, because you formula u(x,y) is the same!

Suppose if you fill in  for f(x) = cos(x) and f(y) =y^2  you get a true equation

@Carl Love ThanksThe mathematical d...

janhardo 700
July 24 2020
0 0

@Carl Love 

Thanks

The mathematical derivation was rather lengthy to follow , but the general solution is

u[x,y] = e^-y.f(x)+g(y) ..all functions of this form substituted in the PDE are true.

As exercise i try to do this now in Maple, to check this  

The idea is to get a impression of the importance of PDE's in this modern world : applications

@ecterrab ThanksInteresting to know...

janhardo 700
July 24 2020
0 0

@ecterrab 

Thanks

Interesting to know more how the PDE can be possibly solved
I did one PDE:  u[x,y]  = - u[x] by hand following: a long calculation to arrive at the general analytical solution equation.
 

This could be a big question  http...

janhardo 700
July 22 2020
0 0

This could be a big question 

https://mathworld.wolfram.com/SingularMatrix.html 

Plane chance and vertical lines...

janhardo 700
July 21 2020
0 0

@janhardo 


 

> 

  restart;
  with(plots):
  with(ArrayTools):
  doPlot:= proc( A )
           local rooster, p1;
            rooster:= plot3d
                       ( 0, 0..op([2, 1, 2], A),
                         0..op([2, 2, 2], A),
                         grid= [op([2, 1, 2],
                         A)+1,
                         op([2, 2, 2],
                         A)+1], style=wireframe,
                         color= COLOR(RGB, .15$3),
                         thickness= 0
                       );
            p1:=spacecurve({[[0,0,0], [0,0,0.5]],[[1,0,0], [1,  0,0.5]],               [[0,1,0], [0,1,0.5]], [[1,1,0], [1,1,0.5]]}, color=black):
            display
                 (  rooster, p1, [ seq
                     ( seq
                       ( plot3d
                         ( A[i,j],
                           x=i-1..i,
                           y=j-1..j,
                           shading=zhue,
                           style=surface,
                           axes=normal,
                           view=[ 0..op([2, 1, 2], A),
                                  0..op([2, 2, 2], A),
                                  min(0, A[..,2] )..max(A[..,2])
                                ]
                         ),
                         i=1..Size(A,1)# 1..5
                       ),
                       j=1..Size(A,2)
                     )
                   ],
                   scaling=constrained,
                   size=[1000, 1000]
                 );
          end proc:
  T1:=Array( [ [ 0.5, -1  ],
               [ 1,    2  ]
             ]
           );
   T2:=Array( [ [ 0.5, -1  ],
               [ 1,    2  ],
              [ 1.5,  1  ],
               [ 1.75, 2  ],
               [ 2,    2.5]
             ]
           ):
  T3:=Array( [ [ 0.5, -1, 3, 4  ],
               [ 1,    2, 4, 6  ],
               [ 1.5,  1, -4, 4 ],
               [ 1.75, 2, 5, 2  ],
               [ 2,    2.5, 2, 2]
            ]
          ):
  doPlot(T1);
  doPlot(T2):
  doPlot(T3):

Matrix(2, 2, {(1, 1) = .5, (1, 2) = -1, (2, 1) = 1, (2, 2) = 2})

  

 
> 

with(plots):
> 

 

> 

p1:=polygonplot3d([[1,1,5],[2,1,5],[2,3,5],[1,3,5]]):
> 

p2:=polygonplot3d([[2,3,2],[3,3,2],[3,4,2],[2,4,2]]):
> 

p3:=spacecurve([[0,0,0],[3,0,0],[3,4,0],[0,4,0],[0,0,0]],color=black):
> 

display({p1,p2,p3},axes=normal,orientation=[-16,78]);

 
> 

p4:=spacecurve({[[1,1,0],[1,1,5]],[[2,1,0],[2,1,5]],[[2,3,0],[2,3,5]],[[1,3,0],[1,3,5]],[[2,3,0],[2,3,2]],[[3,3,0],[3,3,2]],[[3,4,0],[3,4,2]],[[2,4,0],[2,4,2]]},color=black):
> 

display({p1,p2,p3,p4},axes=normal,orientation=[-16,78]);
> 

 

 

 

 

New proc for this existing procedure doPlot

- planes are now made with polygonplot3d .. or use exising plane with borderlines 
-vertical line segments


How to do this ?
Input doPlot is a
T1:=Array( [ [ 0.5, -1  ],
               [ 1,    2  ]
By input this array for example a plane 0.5  has for z = 0.5
For every plane you get 8 points , and must generate this for plotting vertical lines between the points.

 

 

 

> 

 


 

Download arrplot3-1_laatste_tom_leslie1.mw

@vv  He is from Holland  Andr&...

janhardo 700
July 20 2020
0 0

@vv 
He is from Holland  André Heck .. me too. 
For some books: aging is no problem and agree with you.

I bought recently : introduction to Maple from André Heck ,the first edition and brandnew for  8 USD
Got the impression that this book is dated : Maple V release 2 ?

I am interesed in this bookversion, but is it somewhere to find used? 

 

@Carl Love  Seems that the package...

janhardo 700
July 20 2020
0 0

@Carl Love 

Seems that the package is not freely  without copyright issues, so removed links to the package.
5 LAMP commands not working in Maple:  
Drawlines,Drawplanes, Backsolve,Matsolve, Inverse
As i undertstand the coding from this package is not the best one at the moment ( 20 years back)
Is there another free Maple package for maple programming training purposes?
 

 

@Carl Love  What the command for i...

janhardo 700
July 19 2020
0 0

@Carl Love 

What the command for instance Drawlines ( )  excactly does, it is not explained in the section: commands in this module( see worksheet link)
The book text gives more explanation for the  command Drawlines: plot the lines without first having to solve each equation for y

No plotting and there is a error message

Interesting to know this code works?    
 

 

@acer What is wrong with this code ...

janhardo 700
July 19 2020
0 0

@acer 

What is wrong with this code ?

"As I recall, the accompanying code was not a great example of Maple programming, even when less outdated"

Then i could learn from this

@Carl Love ThanksAlso there is no h...

janhardo 700
July 19 2020
0 0

@Carl Love 

Thanks

In folder lampmod all course mws
Also there is no help for the commands from LAMP ?
The LAMP commands are found under: Mathematics...Linear Algebra...Lamp Library...

 

@Carl Love This second new  fi...

janhardo 700
July 18 2020
0 0

@Carl Love 

Note: i removed the link

This second new  file for LAMP- where you asked for-  is a easier one to use then th e first one 

@vv  Thanks Works great for 2 D&nb...

janhardo 700
July 18 2020
0 0

@vv 

Thanks
Works great for 2 D 
For 3 D solids (conics etc)  classification maple has no existing procedure ? 

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