Reference: http://www.iflscience.com/physics/beautiful-mathematical-gifs-will-mesmerize-you

I need to find the local maxima and minima of f(x,y)=x(x+y)*e^(y-x). I have tried to look for an appropriate method that I could use to achieve this, but got stuck. I also don't quite understand the math behind tying to obtain the local maxima and  minima for a function of this type.

I'm trying to evaluate the multidimensional limit: 

(1+y)^(x-1)-1/(1-cos((x-1)^2+y^2)^(1/4)) as (x,y)->(1,0) using the limit command :

limit((1+y)^(x-1)/(1-cos((x-1)^2+y^2)^(1/4)),{x=1,y=0});

but don't seem to get any output. Also, I think the limit for this function doesn't exist or is indeterminate on R2. Where am I wrong?

I am considering options to access Maple features from within a Fortran program using the OpenMaple API. I do not find any examples illustrating this (or even precise statements if this is possible in principle). (Quite surprising to me considering the presence of Fortran in scientific computing).

Is the only way to go to write a C wrapper for the API? If yes, is there an example for such a wrapper which performs common conversions between Fortran and C data types.

Thanks!

Greetings, seeking an expert to animate a plot.

see worksheet.posterior_graphs_(encapsulted)_1D.mw

before they play each other, each have a law (a normal distribution) plot-output 6.

after DD defeats CC, and a numerical integration is performed the new laws are given by plot-output 18.

as you can see, the laws of DD and CC are closer together.

if the calc was repeated (DD defeats CC again), the laws would be closer again.

so what i require is an animation of the new laws from game 1 to (say) game 6 (DD defeats CC every time). seeing the red and blue distributions merging would be ideal.

as an aside I heard maples FFT could simplify the complicated integration. any suggestions?

cheers

I have been Maple  18 with no problem. Then, today, the  "=" symbol and  "+" symbol don't work.  Does anyone know what to do about this?

Hi,
There a lot of symbols that don't work in Maple.
The symbols that dont work are shown as an "A".
Almost half of the symbols in the pallets are shown as an "A".

Hi,

I am trying to discretize a kernel of the form $K(x,y,t,s)$. I want to evaluate a four dimensional integral of the form

\int\int\int\int K(x,y,t,s)*h_m(x)*h_n(y)*h_p(t)*h_q(s) dsdtdxdy, where limits of integration are from 0 to 1.

$h_m()$ are function of one variable.

please suggest how to evaluate this.

thanks

In the attached Maple worksheet I attempt to plot the solution of an initial value problem for a first order ODE.  DEplot fails with a cryptic message.  Strangely enough, if I give the "arrows=none" option to DEplot, it produces the correct plot!

I see this behavior in Maple 17 and 18.

Maple 11, however, works fine with or without the "arrows=none" option.

Is there an explanation for this or is it a bug?

DEplot-bug.mw

restart; macro(x = eta); einf := 4; gm1 := 10; gm2 := 5; mf := .5; pr := 6.2; le := 10; nb := .2; nt := .2; r := 2; tr := 2; bi := .5; m := 2; tr1 := 1.5;
a1 := (m+1)*(1/2);
eqs1 := diff(f(x), [`$`(x, 3)])+a1*f(x)*(diff(f(x), [`$`(x, 2)]))-m*(diff(f(x), [`$`(xx, 2)]))^2+gm1*g(x)-gm2*h(x)-mf*(diff(f(x), [`$`(x, 1)])) = 0;
eqs2 := diff(g(x), [`$`(x, 2)])+a1*pr*f(x)*(diff(g(x), [`$`(x, 1)]))+pr*nb*(diff(g(x), [`$`(x, 1)]))*(diff(h(x), [`$`(x, 1)]))+pr*nt*(diff(g(x), [`$`(x, 1)]))^2+(4/3)*r1*(diff((1+(tr-1)*g(x))^3*(diff(g(x), [`$`(x, 1)])), x)) = 0;
eqs3 := diff(h(x), [`$`(x, 2)])+a1*le*f(x)*(diff(h(x), [`$`(x, 1)]))+nt*(diff(g(x), [`$`(x, 2)]))/nb = 0;
bcs1 := f(0) = 0, (D(f))(0) = 1, (D(f))(einf) = 0;
bcs2 := (D(g))(0) = bi*(g(0)-1), g(einf) = 0;
bcs3 := h(0) = 1, h(einf) = 0;
eqs := {bcs1, bcs2, bcs3, eqs1, eqs2, eqs3};
sol1 := dsolve(eqs, [f(x), g(x), h(x)], numeric, output = listprocedure);

If I typed the above line it's showing 

Error, (in dsolve/numeric/process_input) missing differential equations and initial or boundary conditions in the first argument: eqs

Kindly, I request you to do the needful as early as possible.

hai everyone. i am currently trying to solve an integration of the following ∫g(η)dη . integrate from 0 to 10.

from the following odes.

f ''' +1-(f ')² +ff ''=0,

g''-gf'+fg'=0,

with boundary conditions f(0)=0, f'(0)=λ, f'(∞)=1, g(0)=1,g(∞)=0

First, i solve the odes using the shooting method. then i used the trapezoidal rule to solve for the integration of g(eta) using the following codes

> with(student);
> trapezoid(g(eta), eta = 0 .. 10, 10);
> evalf(%);

it seems that it can not read the data from the shooting method. can anyone suggest why it is happening?

thank you verymuch for your concern :)

Hi

I am trying to implement the following basis functions $h_n(t)$. Please suggest how to implement. thanks

Hello i want to solve the differentiel equation but i have these problem i don't understund  why !?

drive.mw

thanks for your help

Download drive.mw

I have a markov matrix that is 500x500. I need to take the standard deviation of the top row of this matrix after I raise it to high powers, like 10^17 by 10^12, (from a do loop.) I would also like ot make a histogram of this data too. 

Any ideas what I can do? 

I have a pair of markov matrices that are 250x250 and 500x500 in size. I am raising these matrices to high powers, like 10^17 by 10^12. (I'm using a do loop.) If I set digits:=15, Maple will use 100% of the processor that is available. If I set digits:=16+ Maple will only use 1 thread of my processor. Why? It is the same matrix same program. The only thing that changes is the digits of accuracy. This seems exactly backwards from what it should be. As a result, my AMD9590 processor will run full blast when I choose 15 digits of accuracy and gets the biggest matrix done in 1-2 hours. If i set the accuracy to 17 digits, it takes half a day or more to do the same thing!!! 2 digits of greater accuracy should not take an additional 20 hours!

Thanks