Hey everyone.

I have been trying to solve an ODE with BC with dsolve,numeric but always get the error below:

> Error, (in dsolve/numeric/BVPSolve) matrix is singular

My problem is not solving it (ie fine to do with LinearAlgebra package or similar), but why does this error occur? What is the problem with the ODE/BC that produces this error?

And is there a way of adjusting the ODE/BC to be able to solve it simply by using dsolve,numeric?

On my Dell Latitude E5400 laptop with up-to-date Fedora 16:

$ maple15
    |\^/|     Maple 15 (X86 64 LINUX)
._|\|   |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc. 2011
 \  MAPLE  /  All rights reserved. Maple is a trademark of
 <____ ____>  Waterloo Maple Inc.
      |       Type ? for help.
>  log[2](8);

I've been trying to solve eqn1,eqn2,eqn3,eqn4 for T[water],T[air],T[Al],T[plastic] by using the defined variables listed above the set of eqn's, but everytime I get the "Warning, solutions may have been lost". Is there a solution to this or are the eqn's unsolvable?

> restart;
>
> h[infinity] := K[infinity]*(0.37e-1*RE[infinity]^(4/5)-871)*Pr[infinity]^3/L[plastic]:
> h[plastic] := N[plastic]*K[plastic]/L[plastic]:
> h[water...

Problem. Write the equation of the plane passing the point H(1,1,1) and cut the coordinates axes Ox, Oy, Oz at A, B, C respectively so that H is centre of the circumscribed of the trianlge ABC.

This is my code.

restart:

with(geom3d):

with(LinearAlgebra):

A:=:

B:=:

C:=:

H:=:

f:=(x,y,z)->x/a + y/b +z/c-1:

solve([f(H[1],H[2],H[3]) = 0, Norm(H - A, 2) = Norm(H - B, 2), Norm(H - A, 2) = Norm(H - C, 2)],{a,b,c}): assign(%):

Problem. Write the equation of the plane passing the point H(2, 1, 1) and cuts the coordinates Ox, oy, oz at A, B, C respectively so that H is orthocenter of the triangle.

This is my code.

restart:

with(geom3d):

with(LinearAlgebra):

A:= <a,0,0>:

B:=<0,b,0>:

C:=<0,0,c>:

H:=<2,1,1>:

f:=(x,y,z)->x/a + y/b +z/c-1:

eq:=solve([f(H[1],H[2],H[3]) = 0,DotProduct(B-C, A-H, conjugate = false...

Simply using display(array) we can create larger zoomed sized plots that I think some people would like but only for 2d but what about 3d plots ? - read on. 

Now this expands only the width of the plot and works for all 2d plots.
a:=plot(sin(x)):
display(array([a]))  # displays plot at screen width size

What I think most people want is an easy way to adjust plot sizes from the default Maple install without having to load any special packages ...

I've made exam questions for students that they have to answer by doing some calculations in Maple.

I would like to let them copy the commands they used to a Maple TA text field.

However, the standard worksheet in our computer lab uses 2-D math. Copying this 2-D math to Maple TA works fine with "paste as plain text", but copying 1-D math also works with ctrl-v in Maple TA, which is more convenient for students under stress.

Since I am not allowed change...

Hi everyone.

I am currently trying to write the gradient projection algorythm for an optimal control problem with Maple.

This involves calculation of the gradient of the objective function at every new iteration, which would be not a problem per se. However, in optimal control problem this last depends on state and costate variables which, in turn, are given by the system of ODEs. This system is solved numerically only. As far as I understood Maple is recalculating...

Am i undestand right that all GUI-changed properties of plot are not accessable via command-line because with already pictured plot there are no binded variables and no method to bind? For example after manual streching and moving i need to work in interest area of graph i.e. includding new textplots there and so on. See only way to work with via DocumentTools component and it events to get e.g. xrange  and yrange. Is there better way?

Cannot find own answer in

http://www.mapleprimes.com/posts/100884-Precision-And-Plot-Drivers

via searching in my answers. Is it because original message is too old and thats why should be so?

[A]+[B] N+[C] N^(2)+[D] N^(3)+...N^(8)

[A],[B],[C],[D],... is known 8*8 matrix ;

how to find Eigenvalues and Eigenvectors and N?

eig([A],[B],[C],[D],...) ?!?!?

Hi there

I'm a new user of Maple 15 and would really appreciate some tips on how to get started, this time more specifically on how to change the axis orientation. I'm a geotechnical engineer and in practice we always plot all the soil properties (strength, density, water content, etc) with depth, and so it should be positive downwards. 

I've seen a few posts where the issue was raised by some people years ago but was just curious to know if the new version...

Hi all,

I've got the following Maple math code (its called the 'Strickler function', giving a relation between water hight 'y' in a channel and other paramaters), that works like a charm and correctly outputs my function Q =

> restart;
> A := (b+m*y)*y;
> R := A/(b+2*y*sqrt(1+m^2));
> Q := k*A*R^(2/3)*s^(1/2);

However, all contants in the functions are know, except for 'y' (Q is known as well). How do I solve the last equation for...

My problem: Write the equation of the line (Delta) passing the point A(-2;3;4), perpendicular to the line

(l): x = -t + 1, y = 2t, z = 3t + 1

and have a distance from the point B(1;2;-4) obtain

a) maximum;

b) minimum.

Can you write for me a code? Thank you.

Hi,

I would like to know how can I go out from two nested loops. I tried with the command 'break', but it go out only from the one loop. For example,

for i from 0 to 10 do

for j from 0 to 10 do

for z from 0 to 10 do

p:=i*j*z;

if p<=40 then print(p)

else break fi;

od; od;