Bad title, I know. 

Suppose I have solved an ODE numerically, say for a function f(x). Now, I want to solve another ODE numerically, given by

diff(g(x),x) = f(x)*g(x)

I want to solve for g(x), and I only know f(x) from the numerical solution I obtained in the first ODE. How do I implement this in Maple?

I attached a worksheet with my naive attempt with this simple example. Basically I do not know how to set up the differential equation which I would then input to dsolve. 

ode.mw

Thanks!

I am trying to integrate solutions to a set of differential equations I have obtained numerically but keep getting this error:

Error, (in solW) invalid input: subs received sol(r), which is not valid for its 1st argument

For simplicity, let's say I am interested in integrating the function W(r), which I obtain from 

sol := dsolve({eqns, ics}, numeric, abserr = 10^(-10), relerr = 10^(-10), range = ymin .. ymax)

I then use

solW := r -> subs(sol(r), W(y))

This gives me W(r) for any r in the range ymin to ymax. But I cannot do anything with this function. For example, 

int(solW(r),r=ymin..ymax) or plot(solW(r),r=ymin..ymax) give the error above. I know that I can plot the solutions using odeplot, but is there something analogous for integrating the solutions? 

Thanks!

Hello

Previously today I had to do some chemistry assignments, which I did in maple, my long time favorite for such assignments.

However I have now encountered a severe problem. I cannot open my worksheet file, .mw. When I try to open it, it asks me whether to open the file as maple text, plain text or maple input??? 

Whatever one I choose, it either opens a blank page in maple, or maple just crashes.

The file in question should be attached. If you can open it, don't mind the language, it is danish

Any help will be greatly appreciated, best regards, Jens

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/Opgaver_fra_bog.mw .

Download Opgaver_fra_bog.mw

As a very good application for viewing and calculation of the components of acceleration either tangential or normal. Besides immediately it is shown an Application for physics.

Componentes_de_la_Acelelación.mw

(in spanish)

L. Araujo C.

Here we see the projection of a vector onto another using different concepts ranging from linear algebra to vector calculus. Implemented components thus seen in three-dimensional space.

Proyecciones_Vectoriales.mw

(in spanish)

L.Araujo C.

plot([Y2(t),-X2(t),0...100],numpoints=100);

Error, (in plot) procedure expected, as range contains no plotting variable

Here is a serious achievement of the Roots command:

Student[Calculus1]:-Roots(2^x+3^x+6^x-x^2);

                              [-1]

plot(2^x+3^x+6^x-x^2, x = -6 .. 2, gridlines = false);





Download Roots.mw

The solve command also does the job here:

sol := solve(2^x+3^x+6^x-x^2);

allvalues(sol);


evalf(%):

The RealDomain:-solve command fails here.

I wonder how Maple solves it. It would be kind of Maple developers and experts to explain that.

PS. I tried printlevel:=10, but understood the output a little.

Hello

I want to solve this equation in Maple, but I can't - please help me.

60=18+69*e^(-0,0491t)

Thanks.

Hi, i got a litlle problem with fromats, i m realy bad at this.
i got procedure 'getone(z::list)' i was execute it like this  
>getone([seq(lineP[i], i = 1 .. pm)]::list)
where lineP is 

>pm := 3;
>rollx := rand(98.0 .. 102.0); rolly := rand(-1.0 .. 5);
>rolll := rand(.5 .. 1.0); rollf := rand(0. .. evalf(2*Pi));
>rollm := rand(0. .. 20.0);

>for i to pm do lineP[i] := [rollx(), rolly(), rolll(), rollf(), rollm()] end do;

it's pm times of z:=[rollx(), rolly(), rolll(), rollf(), rollm()] ::list

and i need make optimization work for any pm=1..100; with rabdomly generated iteration point as above.

The main queston is how make minimize as below
Minimize(z,variables=[z],   initialpoint={z=[seq(lineP[i], i = 1 .. pm)]},iterationlimit=1000,optimalitytolerance=0.01)

work with z::list kind of 

[[100.7798614, 1.109653266, 0.9840371500, 4.257816686, 9.737110573][100.0135459, 0.887539481, 0.9144164697, 3.980093624, 7.343851161][100.0661308, 3.724268229, 0.5020544909, 2.052134822, 14.37408543]]

I find fsolve() to be curiously unstable. Some of the behaviour I can guess at, but other parts are not as clear.

Define a function.

P := x->fsolve(exp(-(1/100)*t^2)*cos(2*t),t=x):

plot(P,4..5,smartview=false);

I set up a worksheet with embedded components in Maple 18. I am now trying to use the worksheet with Maple 2015. The GetProperty( ) procedure in DocumentTools cannot find a number of kinds of the embedded components (perhaps all kinds).

Why would this happen, and how can I fix it?

Hello

I have a simple list:

xlist := [150, 250, 500, 800, 1300, 2500, 5000]:

ylist := [.3, .5, .8, 1.0, 1.2, 1.4, 1.6]:

where after i said x:=plot(xlist,ylist);

What I want to do is ask maple" At what x value does the graph intersect with 1.5 on the y axis" or "at what y value does the graph intersect with 3000 on the x axis". 

The data points are just that, I've been looking for commands to ask these questions but have been without luck. You don't need to give me the answer if you can point me to somewhere where this information is written, that would be very helpful!

Thank you.

Elast2.mw

Here the potential of maple 2015 to the quantitative study of the decomposition of a vector table is shown in two dimensions. Application for the exclusive use of engineering students, which was implemented with embedded components.

Atte.

Lenin Araujo Castillo

Archivo Corregido:  Decomposición_Vectorial_Corregido.mw

Hello!

Is it possible convert some equations in R² (ellipse, hyperbola) to polar coordinates using Maple? And a regular  object in R³ like a sphere, a cylinder or a cube could be converted from cartesian coordinates to polar coordinates?

Thank you so much.