intsolve(int(f1(u)*(x-y), u = a .. b) = (12)*cos(x)+5*x^2-12, f1(x));I try to resolve the integral equation but i received all the time the followinf message error 

Error, (in intsolve) invalid input: rhs received {f1(x) = ?}, which is not valid for its 1st argument, expr
I try to use different form but i do not how to resolve the help center do not help to much.

I preciate any help thanks

Which book is the starting point and have examples

I am trying to produce an animation. Everything seems correct, but the evaluation is taking a very long time. Even after an hour, it still tries to crank out a graph for me. I even tried to truncate the integral!

Here is my code.

with(plots):

z:= x -> 2*(int((sin(2*y)-sin(y))*cos(y*x)*exp(-y^2*t)/y, y = 0 .. 200))/Pi;

animate(plot, [z(x), x = 0 .. 10, y = -.1 .. 2], t = 0 .. 1, frames = 100);

Would could be the problem? 

Hi all

How to read a value from keyboard of PC when executing a maple document and assign it to a variable ?

Thanks

> with(DEtools);
> L := -1.576674; MU := 0; DE13 := {(D(x))(t) = x(t)*(1+4*x(t)*x(t)-y(t)*y(t))+MU*y(t)*(x(t)*x(t)-.43*y(t)*y(t)-L), (D(y))(t) = y(t)*(1+x(t)*x(t)-.5*y(t)*y(t))+MU*x(t)*(x(t)*x(t)-.43*y(t)*y(t)-L)}; DEplot(DE13, [x(t), y(t)], t = 0 .. 20, [[x(0) = 0.1e-1, y(0) = .99], [x(0) = -.1, y(0) = -.9], [x(0) = 1.1, y(0) = 0], [x(0) = 0, y(0) = .2], [x(0) = 0, y(0) = .6], [x(0) = .6, y(0) = 0], [x(0) = .75, y(0) = 1], [x(0) = .1, y(0) = .1], [x(0) = .5, y(0) = 1.0], [x(0) = -.5, y(0) = 1], [x(0) = .5, y(0) = -1], [x(0) = -.5, y(0) = -1], [x(0) = -0.1e-1, y(0) = .99], [x(0) = 0.1e-1, y(0) = -.99], [x(0) = -0.1e-1, y(0) = -.99], [x(0) = .5, y(0) = -1], [x(0) = -.5, y(0) = -1], [x(0) = 0.1e-1, y(0) = .9]], stepsize = 0.1e-1, scene = [x(t), y(t)], title = "phaseplane 3 prime plot", linecolor = black, thickness = 1);
-1.576674
0
/ / 2 2\
{ D(x)(t) = x(t) \1 + 4 x(t) - y(t) /,
\

/ 2 2\\
D(y)(t) = y(t) \1 + x(t) - 0.5 y(t) / }
/
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .93908020e-1, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .26367741, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .23463732, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of 1.7040014, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .62484768, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .62484768, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .62484768, probably a singularity
Warning, plot may be incomplete, the following errors(s) were issued:
cannot evaluate the solution further right of .62484768, probably a singularity

what do i need to do so there are no more singularites?

i cant find the error the program is saying i have 

> L := -1.576674; MU := 0; DE13 := {D(y)*t = -x(t)*(1-2*x(t)*x(t))+MU*y(t)*(x(t)*x(t)-3*y(t)*y(t)-L), (D(x))(t) = y(t)*(1-y(t)*y(t))+MU*y(t)*(x(t)*x(t)-3*y(t)*y(t)-L)}; DEplot(DE13, [x(t), y(t)], t = -20 .. 20, [[x(0) = 0.1e-1, y(0) = .99], [x(0) = 0.5e-1, y(0) = .95], [x(0) = .1, y(0) = .9], [x(0) = 0.4e-1, y(0) = .96]], stepsize = 0.1e-2, scene = [x(t), y(t)], title = "phaseplane plot", linecolor = black, thickness = 1, number = 1000);
 
Error, (in DEtools/DEplot/CheckInitial) too few initial conditions: [x(0) = 0.1e-1, y(0) = .99]

it might be hard to read but if someone could help me it would be very appreciated 

For some time I have been running into the problem where uploaded worksheets that are inlined into a Mapleprimes post get gridlines shown, even when they are not specified or shown in the original worksheet. This is a problem because quite often the gridlines make an inlined plot unattractive.

I believe that Mapleprimes uses some version of MapleNet as a mechanism for inlining uploaded worksheets.

It seems that the Standard GUI and/or MapleNet have special handling for gridlines in the sense that they actually distinguish between PLOT structures generated without the `gridlines` option versus those created with `gridlines=false`.  I believe that this has something to do with the persistence of various plot qualities in an output region which (perhaps for historical reasons?)  allow re-execution of a plot input command to produce a plot output rendering that remembers whether gridlines are visible.

If the second plot below does indeed get rendered here in Primes without gridlines visible then one workaround is evident: adding `gridlines=false` instead of omitting the option.

Download test.mw

I'll submit a bug report against MapleNet.

acer

Hello,

I am having trouble using the programmer entry point interface to convert/parfrac. As an example consider : While

> convert([x, [I*(x+I), 1]], parfrac, x);                   

         [-I, [(I + x) I, -I]]

correctly computes a partial fraction decomposition, the equivalent input

> convert([x, [I*x-1, 1]], parfrac, x);  

results in the error message (both in Maple 16 and 17)

Error, (in convert/parfrac) denominator factors must be coprime

which does not make any sense to me, since there is only a single denominator factor present (and it is even the same factor as in the previous call, only written differently).

What is the reason for this behaviour and how can I use convert/parfrac in a way that avoids such errors?

Thanks,

Erik

Hello

I'm doing some calculation reports in maple. These reports are to be submitted to various classification societies - which all have different requirements to the calculations.

I would like to make a report, where the class specific calculations would be append based on a selection of class in the main calculation.

How do I do this?

If I was using latex, matlab, APDL or something like that, I would do and *IF Class=class1, *INPUT class.calc, *ENDIF, but how to do this in maple?

Hi

I need a temperature distribution inside a barrier during a heating process.
I will be appreciated for any help.

wz

Download heating.mw

Hi

I use Maple perhaps only one time per year and thus i'm a beginner with the product (even if i use it since 1996). I'm trying to make the following script work in Maple 17:

http://www.maplesoft.com/applications/view.aspx?SID=4268&ref=Feed&L=F

but i fail.... Some help will be appreciate

restart:

Eq1:=1/r*diff(r*diff(w(r),r),r)-(cos(z1))^2*(w(r)+1)-DP;

dsolve({Eq1});

bcs:=D(w)(0)=0,w(r2)=A1;

dsolve({Eq1,bcs},w(r)):

where z1, Dp, r2, A1 are constants.

Hi, can I get some help with this?

The question is:

Consider the following IVP for a mass of m = 2 kg attached to a spring with a spring constant k = 9 N/m. The spring mass system is in a medium with damping constant b.

2y" + by' + 9y = 0

y(0) = 0, D(y)(0) = -3 

It then asks find three values b1, b2, b3 where b1 is underdamped, b2 is critical, b3 is over. 

I set b1 as 1, b2 as sqt 72, b3 as 9. 

Then it asks to find the quasi period. 

I can't get my quasi period right. My answer is 2pi/ sqrt (4.5).

Any help?  

Hi.

Please, I need a code in maple for adaptative setp size control for runge Kutta.

Thank you.

Hi.

Please help to use dsolve.

Suppose I have a Matrix A of size two. Y=[u,v].

Y'(t)=A*y(t).

How can use dsolve this problem.

Thanks