Advanced Search

janhardo

335 Reputation

8 Badges

11 years, 7 days
Contact janhardo

MaplePrimes Activity


These are questions asked by janhardo

How to calculating gradient as function...

janhardo 335
vectorcalculus gradient
August 28 2020
2 8

In old studymaterial i could calculate  a gradient in (1,-1,2)   with obselote   package linalg 

f:= (x,y,z)->exp(x*y^3*z^2);

gradf(1, -1, 2); # werkt wel
              [-4 exp(-4), 12 exp(-4), -4 exp(-4)]

But i couldn't do it with the LinearAlgebra  or VectorCalculus package ?
LinearAlgebra has no gradient command, so left over Vector Calculus what is the right place 

Something chanced in DEtools ?...

janhardo 335 Maple V
ode detools differential-equations
August 27 2020
1 8

CH10A.MWS

Old worksheets with linear algebra...

janhardo 335
linearalgebra linalg
August 17 2020
2 1

Try to convert the old worksheet to the modern linear algebra package ( student )? 


 

> 

restart:
> 

with(LinearAlgebra):
> 

 

> 

v1:=(3/4-lambda)*x1+3*x2+2*x3=0:
> 

v2:=3/4*x1-lambda*x2=0:
> 

v3:=1/3*x2-lambda*x3=0:
> 

stelsel:={v1,v2,v3}:
> 

 

 

        We bepalen nu de bijbehorende determinant, en onderzoeken voor welke waarden van    deze

        determinant  0  is:

 

> 

C:=Matrix([[3/4-lambda,3,2],[3/4,-lambda,0],[0,1/3,-lambda]]);

Matrix(3, 3, {(1, 1) = 3/4-lambda, (1, 2) = 3, (1, 3) = 2, (2, 1) = 3/4, (2, 2) = -lambda, (2, 3) = 0, (3, 1) = 0, (3, 2) = 1/3, (3, 3) = -lambda})

 (1)
> 

solve(det(C)=0);

Error, (in Engine:-Dispatch) badly formed input to solve: not fully algebraic

  
> 

 

 

  

   Nu onderzoeken we, wat de bijbehorende oplossingen zijn:

 

     Voor   :   λ "= - 1/(4)"

 

> 

lambda:=-1/4:
> 

solve(stelsel);

{x1 = x1, x2 = -3*x1, x3 = 4*x1}

 (2)
> 

 

===========================================================
Maple v 4

> 

 

> 

 


 

Download uitw_03_m_recent.mw

 

 

How to get this Maple V R4 worksheet in ...

janhardo 335 Maple 2020
classic worksheet
August 15 2020
0 8

Got a lot of worksheets who are not complete anymore once opened in maple 2020

It can be only opened with a old version of Maple
Can it be imported in Maple 2020?

example 

Dynmod03.mws

The right notation for a ode ? ...

janhardo 335 Maple
derivative ode syntax
August 15 2020
1 1

Found in old studymaterial about Loka-volterra ode 

dsolve({D(N)(t)=r*N(t)-k*N(t)^2,N(0)=N[0]},N(t));

Seems to me not logical notation to use a D operator  : D(N)(t)  for this ode : makes it unneeded complicated this notation..or do i miss something?

First 8 9 10 11 12 13 14 Last Page 10 of 18