hi .how i can solve nonlinear equation with unknown prameter omega as below

thanksfrekans.mw

Hi All,

I have o problem with simplify. A variable cp1r has been assumed to be positive. Why simplify still has csgn(cp1r) for it? Here is my code:

tmp := subs(cp1t(t)=cp1r, cp2t(t)=cp2r, Ca[2]);
1 / 2 2
----------- |-cp2r sin(x[1]) sin(x[7]) cp1r
2 2 |
cp1r cp2r |
\

2
+ 2 cp2r sin(x[1]) cos(x[1]) cos(x[7]) sin(x[7]) cp1r +

1 / 2 2 /
-------------- \cp2r cos(x[1]) cos(x[7]) sin(x[7]) \
(1/2)
/ 2\
2 \cp1r /
2 \\\
-2 cos(x[1]) cos(x[7]) sin(x[1]) + 2 sin(x[1]) cos(x[1])//|
|
|
/
assume(cp1r > 0, cp2r > 0);
simplify(tmp);
1 / / 3 3
---------- \sin(x[1]) sin(x[7]) \-cos(x[1]) cos(x[7])
2
cp1r cp1r

+ 2 cos(x[1]) cos(x[7]) cp1r csgn(cp1r) cp1r

2 3 \ \

- cp1r csgn(cp1r) cp1r + cos(x[1]) cos(x[7])/ csgn(cp1r)/

should csgn(cp1r) be simplified to 1 already? What is wrong with my script?

Thanks 

Everett

Maple does not cope with the following simple example:

with(geom3d):

point(A,0,0,0), point(B,1,0,0), point(C,2,0,0), point(E,2,1,0):

AreCoplanar(A,B,C,E);

           Error, (in geom3d:-plane) the points may not be AreCollinear

Should we interpret this behavior as a bug? I think I met with this yet 10-12 years ago, but unfortunately since then nothing has changed.

I have the following PDE:

u_xx = u_tt + (2^{1/2}u_x-u)^{1/2}

Do you have a proposed algorithm to solve in maple for this PDE? I mean pdsolve won't solve it because it's a nonlinear PDE.

Hi All,

I am working on modeling dynamics for a robot. It requires a write some long expressions into C++.  When I do it, it has some strange problem in creation of C++ code from a vector.

Here is an example of the problem. I have a multivariable polynomial term, I using coeffs to get its coefficients and corresponding unevaluated variables, which works fine. But I can't convert the vector into C++

Ca := coeffs(term, [W, Rf, Rr, dxf, rcf, rcr], 'L'):

L;                           Rf, Rr, dxf

C(L, resultname="L11", output="dSpDdx1.cpp");

Error, (in Translate) options [Rr, dxf] not recognized.

I don't know why maple thought the unevaluated variable Rr and dxf are options instead of the vector I want to convert into c++. Does any one know what I did wrong?

Thanks in advance.

Everett

Just purchased Maple 2015 and playing with it for the first time.  I'm running the 64-bit version on Win 8.1.

Anytime the program generates a pop-up dialog box, the pop-up seems to get stuck behind the main program window.  I can't alt+tab to get to the pop-up window and I can't click on anything in the main program window because it's frozen while waiting for me to aknowledge the pop-up dialog box.  So I have to kill everything from the task manager and lose anything that's unsaved.

I'm talking about pop-ups for things like "Error, (in @@) invalid arguments"... I click on the link and see a brief flash while that pop-up quickly flies behind the main window.  Same thing happens when I click on a link that asks what web browser I want to use.

I can't be the only one that has this problem, so is there a fix or workaround for this somewhere?  It's not really useable like this.  Thanks!

k^4-k^2*(4*u*m+2*q^2)+k*(8*m*E*q)+4*m^2*(D^2-e^2+(q^2/2*m-u)^2)=0

This is my first attempt at trying the units feature within Maple. I have had mixed results. I have a function defined that gives me values in [cal/mol/K], which is correct. But when I try to use this as the integrand in an integral definition it does not want to solve. I cannot determine what the problem is.

I thought that I possibly needed to define units in the integral expression, but this just produces more errors or locks-up Maple completely. (Side note: When Maple locks-up, the "interupt current operation" toolbar often does not correctly kill the operation, and I am forced to restart Maple :/)

As I have the problem defined, I should get the following result:

T__sys= 64.47487 [K], should get me HIG(T__sys) = -19682.7 [cal/mol].

See attached: EnthalpyTrace_-_Integrating_with_Units_Error.mw

Any help or insights would be greatly appreciated.

LE_EQ.mwWhat is problem with this programme,why it does'nt calculate the values but only shows the solution with integral sign instead of calculating it, there is also arising a problem in plots

dsolve thousands of system with for loop

but one of system run a very long time, seems never end, just stuck here

how to set timeout when impossible to dsolve

ics:=a(1)=0,b(1)=0,c(1)=0:
ode:=rhs(a4[ii])[1]=1,rhs(a4[ii])[2]=1,rhs(a4[ii])[3]=1:
ode:=a(t)*c(t)*(diff(c(t), t))+2*a(t)*(diff(a(t), t))*b(t) = 1, a(t)*(diff(a(t), t))*b(t)*(diff(b(t), t))*c(t)*(diff(c(t), t))+a(t)*(diff(a(t), t))*b(t)*(diff(b(t), t))+a(t)*(diff(a(t), t)) = 1, a(t)*(diff(a(t), t))*c(t)+2*a(t)*b(t)*(diff(b(t), t)) = 1;
dsol := dsolve({ode,ics}):

Does Maple TA work in Windows 10?

My first attempt in Edge and Chrome was not promising.

Harry Garst

hello guys,

i have 4 differential equations with 4 unknown functions and i want to find functions , what is your idea ?

diff.mw

thank you very much

Hello, Currently when I calculate something, for example R=U/A where R is resistance, U is voltage and A is current, I get the answer in Volt/Ampere in stead of ohm. How do I change that?

Then, if the result is something like 3.124*10^-4 , how do I make maple output this in an engineering way, this would be 10^3, 10^6, 10^9 etc. to begin with?

Sorry if I formulate this wrongly, English is not my first language and I could not find an answer to this after some research.

Thank you

UPDATE and solution: for future reference:

You don't need to type out the whole unit like this:

1.0*Unit(volt)/(2000.0*Unit(ampere));

in stead you can do this:

(1.0*V)/(2000.0*A);

I got the V and A from the SI Units palette on the left hand side,

 ---

To answer my own question about the engineering notation, this can be "forced" by clicking on "Format" -> "Numeric Formating..." -> Engineering and then choosing the number of decimals. apply and set as default. After you are going to have to copy and recalculate your math as the !!! wont do it.

hi guys, i have a complicated 4 set equations and i want to solve it,

one way is to find a solution for an equation and check it manually in other equations but i am looking for better method

eqq.mw

thanks

Hello. My question is in the attached file.

Question.mw