Maple 2015 Questions and Posts

These are Posts and Questions associated with the product, Maple 2015

Hi, i got this diff ecuation to answer. It is an ecuation of a proyectile, it give the angle of speed with respect to time. I typed it on wolfram; got an aswer. When i tried on maple without any initial condition, got a good answer. With an initial condition, didn't get nothing. I even tried with the interactive solver, got a 'can't solve'. So this is my ecuation:

dx/dt = -[g cos(x)] / [vo - g t sin(x)]

I had to find the initial coindition for myself after that, i supect what the problem is. Maple gave an aswer in terms of arctan (y,x), and i think, based on my own try, it doesn't know how to find a term if it's inside the arctan function, typed in that way. So i rewrited it like arctan (y/x), anf found my constant C1.

 

Another problem i got was about this system of diff ecuations:

dx/dt = (-k/m) (x srqt(x^2 + y^2))

dy/dt = (-k/m) (y srqt(x^2 + y^2))

Again was wolfram who gave me a good answer to the problem. So you are going to understand im thinking wolfram is better on symbolic calculation. Thanks anyway for your help and effort.

 

 

 

 

I want to use while in proc but Maple shows an error saying

 

"Error, (in exa) illegal use of a formal parameter"

 

When I click on it, as usual it says "There is no help page available for this error". I tried a very simple example of while which you can see it below and it again shows same error. The while works well but when I put it inside of a procedure it makes an error. Note: the following example is just an example, this is not what I'm doing so please don't reply this while proc is not giving anything. My question is how can I use a while in procedure without encountering the above error.

 

i := 10;
while i > 1 do
if i mod 2 = 0 then i := i/2; else i := i+1; end if;
end do;

 

Now with proc

 

exa := proc (i::integer)::integer;
while 1 < i do
if i mod 2 = 0 then i :=i/2; else i := i+1; end if
end do; 
end proc;

exa(10);

"Error, (in exa) illegal use of a formal parameter"

I need some help fix my mathematics maple code problem , I define everything my Procedures,and procedures run is ok, but when I using call functions for another procedures  I can not operator my program . For sure procedures is work and correct. if somebody can help me , I really appreciate you help.

hi .please help me for this error

Error, (in fprintf) number expected for floating point format...

float.mw

T(r, t) := -(1.082744105*(.4426072302*BesselJ(1, 1.511248492*r)+.5201541352*BesselY(1, 1.511248492*r)))*Besselj(0, 3.588021808)*(1.-1.*exp(-3.218475123670897216*t))/Besselj(1, 1.794010904)-(0.7489242453e-1*(-.4693819312*BesselJ(1, 2.197141326*r)+.6841159909*BesselY(1, 2.197141326*r)))*Besselj(0, 9.604121522)*(1.-1.*exp(-23.059787552335899121*t))/Besselj(1, 4.802060761)-(0.1290812036e-1*(-.6766364675*BesselJ(1, 3.111788255*r)-.7242359729*BesselY(1, 3.111788255*r)))*Besselj(0, 15.817923424)*(1.-1.*exp(-62.551675361881970944*t))/Besselj(1, 7.908961712)-(0.5633715672e-1*(.8435152108*BesselJ(1, 4.692507174*r)+.8812474286*BesselY(1, 4.692507174*r)))*Besselj(0, 9.604121522)*(1.-1.*exp(-23.059787552335899121*t))/Besselj(1, 4.802060761)-(0.6254981294e-1*(-.8481299777*BesselJ(1, 5.429681040*r)+1.002082035*BesselY(1, 5.429681040*r)))*Besselj(0, 9.604121522)*(1.-1.*exp(-23.059787552335899121*t))/Besselj(1, 4.802060761)

-1.082744105*(.4426072302*BesselJ(1, 1.511248492*r)+.5201541352*BesselY(1, 1.511248492*r))*Besselj(0, 3.588021808)*(1.-1.*exp(-3.218475123670897216*t))/Besselj(1, 1.794010904)-0.7489242453e-1*(-.4693819312*BesselJ(1, 2.197141326*r)+.6841159909*BesselY(1, 2.197141326*r))*Besselj(0, 9.604121522)*(1.-1.*exp(-23.059787552335899121*t))/Besselj(1, 4.802060761)-0.1290812036e-1*(-.6766364675*BesselJ(1, 3.111788255*r)-.7242359729*BesselY(1, 3.111788255*r))*Besselj(0, 15.817923424)*(1.-1.*exp(-62.551675361881970944*t))/Besselj(1, 7.908961712)-0.5633715672e-1*(.8435152108*BesselJ(1, 4.692507174*r)+.8812474286*BesselY(1, 4.692507174*r))*Besselj(0, 9.604121522)*(1.-1.*exp(-23.059787552335899121*t))/Besselj(1, 4.802060761)-0.6254981294e-1*(-.8481299777*BesselJ(1, 5.429681040*r)+1.002082035*BesselY(1, 5.429681040*r))*Besselj(0, 9.604121522)*(1.-1.*exp(-23.059787552335899121*t))/Besselj(1, 4.802060761)

(1)

``

F53 := proc (t) options operator, arrow; eval(T(r, t), r = 1.5) end proc; G53 := proc (t) options operator, arrow; Re(evalf[20](F53(t))) end proc; Temp3 := cat("T-t (N=", No, ",r=1.5).dat"); fd53 := fopen(Temp3, WRITE, TEXT); i := 0; for i from 0 by 0.5e-1 to 500 do tt := i; y := eval(G53(t), t = tt); fprintf(fd53, "%10.5e %10.5e  \n", tt, y) end do; fclose(fd53)

proc (t) options operator, arrow; eval(T(r, t), r = 1.5) end proc

 

Error, (in fprintf) number expected for floating point format

 

``

``


Download float.mw

if i install maple 2015 in amazon cloud, activate with my license

and i do not use amazon after several trial, 

will the license be used and can not activate in future if i use amazon cloud again in future?

any command or configure needed when using large amount memory such as 100GB memory?

how to convert baby monster group into permutation group and iterate baby monster to display all permutation group?

if not convert to permutation group directly, 

how to convert to matrix group first and then convert to permutation group?

Hello,

 

I got two problems creating a 3d-plot. First, as the title mentions, I want to cut out a distinct interval from my 3d-Plot.

For example when the graph is displayd from -y_max to y_max but I just want it to be shown from -y_max to -5 and from 5 to y_max again.

I also got a second question:

Another thing I want to do with this graph is redefining this axis with a parameter which is directly dependant from it.

Like for example I want to redefine the "y" axis with a" k" axis with k=y*2, so that in the end I have th

hi.i have a problem with gain Eigenvectors

please help me

thanks

lorenz_1.mw

restart; with(LinearAlgebra[Modular]); A := Matrix(3, 3, [[-a, a, 0], [0, 0, -sqrt(l.b.c.(h+k))/(h+k)], [(2.*h.sqrt(l.b.c.(h+k)))/(l.(h+k)), (2.*k.sqrt(l.b.c.(h+k)))/(l.(h+k)), -c]])

A := Matrix(3, 3, {(1, 1) = -a, (1, 2) = a, (1, 3) = 0, (2, 1) = 0, (2, 2) = 0, (2, 3) = -(`.`(l, b, c, h+k))^(1/2)/(h+k), (3, 1) = 2.*(h.((`.`(l, b, c, h+k))^(1/2)))/(l.(h+k)), (3, 2) = 2.*(k.((`.`(l, b, c, h+k))^(1/2)))/(l.(h+k)), (3, 3) = -c})

(1)

Sol := LinearAlgebra[Eigenvectors](A)

Error, (in evala/preproc3) floats not handled yet

 

``


Download lorenz_1.mw

My question is related to changing the plot size and modifying the number of ticks.

For example, I am plotting y vs. x, and x is from -1.0*Pi/2..1.0*Pi/2. I want to modify the plot size with size=[h,w]. If I have three ticks in x-axis if I change to small width, then the number of ticks is decreased. How can I force it to have the certain number of ticks? Also, why if I set view=[-1.0*Pi/2..1.0*Pi/2,0..1] then the -1.0*Pi/2 disappear if the width size is small. 

Thanks,

Baharm31

Hello people in the mapleprimes,

I have a question, so I hope someone give me answers to it.

I calculated for the solution of the follwing differential equation.

restart
b:=diff(y(x),x)+a*y(x)=f(x);#where a and f(x) is not specified.
dsolve(b,y(x));

subs({f(x)=exp(x),a=2},%);where f(x) and a are specified.

c:=value(%);

The solution of the above was

y(x) = (1/3)*exp(x)+_C1/(exp(x))^2,  (A)

where please note that the second term takes

the form of fraction _C/(exp(x))^2.

 

On the other hand, next I calculated the following differential equation where f(x) and a are specified from the start.

restart
d:=diff(y(x),x)+2*y(x)=exp(x);

dsolve(b,y(x));

Then,

y(x) = (1/3)*exp(x)+exp(-2*x)*_C1  (B)

was the obtained solution.

 

Each (A) and (B) are the same substantially mathematically. But, for Maple, the variable powered to minus brabra

is not the same as one over variable powered to brabra, so that (A) and (B) takes different forms, and maple will see them 

different with each other.

 

  Surely, with algsubs, algsubs(_C1/(exp(x))^2=exp(-2*x)*_C1,c) transforms (A) to (B).

But, I want to know whether there are some other ways than that  to modify (A) to (B).

If there are any good ways for it, I will be happy if you teach them to me.

Thanks in advance.

 

taro

DEAR SIR,

PLEASE HELP ME WITH THAT QUESTION

I am trying to use y* to label a point on the axis of a graph made with DEplot, and am currently unable to.


with(DEtools);
NLC := diff(y(t), t) = k*(Am-y(t));
Am := 20; k := .1;
ivs := [y(0) = 10, y(0) = 30, y(0) = 50];
DEplot(NLC, y(t), t = 0 .. 20, ivs, tickmarks = [default, [20 = y^`*`]], font = [default, default, 30]);

makes y`*` apear as the label, as does the code

tickmarks = [default, [20 = y^`&ast;`]]

wheras if i remove the `` marks I get an error

 

 

 

MAPLE 15 on Windows 10

I have a file on which I can no longer open. This happened after my computer made me long on again after being gone for a little while. Maple was not running when I got back on. This is not unusal and I just clinck on the file and restart.

This time this did not work.

It comes up with a message asking me to select an input mode. Whatever I select even 'Plain text' it just hangs.

I'd send you an image, but I don't see how to do it. The button provide only allows for something with  url and the snip I made is on my desktop.

I need to get thiis worksheet back. I've put a lot of effort into it.

-Traruh

hi 

how i can apply this differential in maple?

thabks...

 

First 41 42 43 44 45 46 47 Last Page 43 of 71