Hello everyone. does anyone please correct my worksheet? I
 

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am trying to solve but could not get the required answer

how I can I get MAPLe to simplify this to Pi/2-beta ,

simplify(arctan(sin(beta)/cos(beta)),arctrig) assuming beta<Pi/2,beta>0;

simplify(arctan(sin(beta)/cos(beta)),symbolic) assuming beta<Pi/2,beta>0;

why i can't get Pi/2-beta

https://www.mapleprimes.com/questions/219048-Help-File-Edit-After-Storing-In-A-Database

I found a previous post which contained a worksheet script for creating help, but this example is likely out-of-date. Can anyone provide a similar example for post-2018 help files to save me considerable trial and error.

I want to open an external *.XML file and put this information in a list (every part is a row). Later, i will change a specific row with other text. Finally, I want to copy all this changes in the same file (rewrite the file).
Someone to help me?

> den := -(-(conjugate(chi)-conjugate(phi))*(chi+phi)*conjugate(lambda)+lambda*(conjugate(chi)+conjugate(phi))*(chi-phi))*(-(conjugate(chi)+conjugate(phi))*(chi-phi)*conjugate(lambda)+lambda*(conjugate(chi)-conjugate(phi))*(chi+phi));

> phi:=exp(I*lambda*(x-t/(4*lambda^2)-w^2)):chi:=exp(-I*lambda*(x-t/(4*lambda^2)-w^2)):

> den1:=simplify(dsubs({phi,chi},den));

> dsubs({exp((1/4*I)*(4*lambda^2*w^2-4*lambda^2*x+t)/lambda), exp(-(1/4*I)*(4*lambda^2*w^2-4*lambda^2*x+t)/lambda)}, 4*conjugate(lambda)^2*cos((1/4)*(4*w^2*lambda^2-4*x*lambda^2+conjugate((4*lambda^2*w^2-4*lambda^2*x+t)/lambda)*lambda+t)/lambda)^2-4*conjugate(lambda)^2*cos((1/4)*(-4*w^2*lambda^2+4*x*lambda^2+conjugate((4*lambda^2*w^2-4*lambda^2*x+t)/lambda)*lambda-t)/lambda)^2+8*abs(lambda)^2*cos((1/4)*(4*w^2*lambda^2-4*x*lambda^2+conjugate((4*lambda^2*w^2-4*lambda^2*x+t)/lambda)*lambda+t)/lambda)^2+8*abs(lambda)^2*cos((1/4)*(-4*w^2*lambda^2+4*x*lambda^2+conjugate((4*lambda^2*w^2-4*lambda^2*x+t)/lambda)*lambda-t)/lambda)^2+4*cos((1/4)*(4*w^2*lambda^2-4*x*lambda^2+conjugate((4*lambda^2*w^2-4*lambda^2*x+t)/lambda)*lambda+t)/lambda)^2*lambda^2-4*cos((1/4)*(-4*w^2*lambda^2+4*x*lambda^2+conjugate((4*lambda^2*w^2-4*lambda^2*x+t)/lambda)*lambda-t)/lambda)^2*lambda^2-16*abs(lambda)^2)

Since "cos(...)" appears in every term in last equation (except a last one), how to common it? 

The  galois routine returns the group of  polynomials within quotation marks, e.g.  "6T1".

How to convert  things like  "6T1"  into just   6T1, i.e. how to get rid of the quotation symbols?

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I'm trying to document some generator calculations that use terms line Xd'. In Maple that turns into a derivative. I converted several 'ed variables into atomic variables. They have made my work sheet unusable. They appear to randomly loose connecin to their assigned values and prevent numeric solutions by showing  up in symbolic form. Once this happens, I have to check each instance where the variable isuse to find where the loss/lossses occured. (copy and past each instance of the variable and check its value).

Once found I can't find a consistant way to re-associate them with the assigned value.

Any suggestions. See botton of attaced work sheet.

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/WS_Gen_I_and_E_for_fauls_on_HS_of_GSU_-_Time_Response_&_51V_Trip_Times_-R5a.mw .
 

Download WS_Gen_I_and_E_for_fauls_on_HS_of_GSU_-_Time_Response_&_51V_Trip_Times_-R5a.mw

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/WS_Gen_I_and_E_for_fauls_on_HS_of_GSU_-_Time_Response_&_51V_Trip_Times_-R5a.mw .
 

Download WS_Gen_I_and_E_for_fauls_on_HS_of_GSU_-_Time_Response_&_51V_Trip_Times_-R5a.mw

How to define 4 functions from the dsolve solution of a system of 4 differential equations?

restart: with(plots): with(DEtools):with(LinearAlgebra):with(Statistics):with(CurveFitting):with(Optimization): 
ddesys := {diff(S(t),t) = -beta*S(t)*Ix(t)/N, 
diff(Ex(t),t) = beta*S(t)*Ix(t)/N - sigma*Ex(t-tau__1),
diff(Ix(t), t) = sigma*Ex(t - tau__1)- gamma*Ix(t-tau__2), 
diff(R(t),t) = gamma*Ix(t-tau__2), 
diff(Dx(t),t) = delta*Ix(t), 
S(0) = 80900, Ex(0) = 1, Ix(0) = 1, R(0) = 0, Dx(0) = 0 }:
dsn := dsolve(eval(ddesys, {beta = 4, gamma = 0.0478, sigma = 0.10, delta = 0.0005, N=80900, tau__1 = 1.1,tau__2 = 8.7,tau__3 = 0}), numeric):
 

Hi,

Please can you give me a hand with numerical solving and visualising the partial differential wave equation with stochastic term eta(t), using methods of stochastic calculus?

diff(u(x, t), t $ 2) - (1+eta(t))*diff(u(x, t), x $ 2) = 0

I had a look at the "stochastic" package by Sasha Cyganowski, but couldn't find an example for stochastic pde.

Look forward to your help.

Thanks,

Dmitrii

Here is a known probability riddle:

A and B are two lists of 100 binary numbers:

A:=[0,1,0,1,0,1,1,0,1,1,1,0,0,1,1,1,1,0,1,0,1,0,1,0,1,0,1,1,0,1,0,1,0,0,0,1,0,1,0,1,0,1,1,1,1,1,0,0,1,0,1,0,1,0,1,0,1,1,1,0,1,0,1,0,0,0,1,1,1,1,0,0,0,1,0,1,0,0,0,0,0,1,1,1,0,1,0,1,0,1,0,1,0,0,0,1,1,0,1,0]:
B:=[0,1,1,0,1,1,0,1,1,1,0,1,0,0,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,1,0,0,0,1,0,1,0,1,1,0,1,1,0,0,0,0,0,0,1,0,1,1,1,0,0,0,1,0,1,0,0,0,0,1,0,0,0,0,1,0,1,1,1,1,1,1,0,0,0,1,1,1,1,1,1,1,0,0,1,0]:

One was obtained by tossing a coin (1 for a head, 0 for a tail), and the other by a human, who was asked to simulate tossing a coin.

Question: which one comes from a human brain?
The standard answer: B was produced using a coin, because (among other things) the probabilty of obtaining a "000000" or "111111" is about 80%, but a humain brain tends to avoid such "simulations".

My Question: what (if any) statistical test can be used in Maple for an answer?
(I have tried ChiSquareSuitableModelTest but both lists were accepted).

# I solved the differential equation using a fourier series decomposting method. I found with the help of "Dsolve" the different expressions of the fourier constants and now I will apply the boundary conditions to find the expressions of its constants.

#this my boundary conditions

#this my system of equations

Recently Maple started freezing on me for a few minutes; after that it continues to work and then freezes again and so on (it does not so much freezes as it pauses).  I do not know what changed on my system (which is Windows 10) for this to happen.  I had been using Maple 2019 when this started and then upgraded to Maple 2020 but that did not solve my problem.

It does not seem to have to do with the type of computations I am doing.

I have problem with usage of solve for the solution of the system of six and eight symbolic equations. I need to get expressions for variables: R__xl, R__xs, R__xsi, R__zl, R__zs, R__zsi, dbeta__l(t), dbeta__s(t). I tried to find solution for 8 equations, but I got the message: Warning, solutions may have been lost. I thought that the system is non-linear and tried to solve it for six variables (R__xl, R__xs, R__zl, R__zs, R__zsi, R__xsi), in this case equations are linear, but Maple ignored the solve command and did not give a solution or error. Could someone help me with this problem?

Quasi-static.mw

Hello

I am not sure how to choose between Threads:-Seq and Grid:-Seq.  

The problem:  a procedure, proc1, that calls two other procedures, proc2 and proc3, verifies if a set of parameters fulfills a certain condition. Proc1, proc2 and proc3 are not part of Maple available functions.  

Right now I am using Grid:-Seq to return the result of applying proc1 to chunks of a thousand parameters.  I wonder whether I could use Thread:-Seq instead.   What are the advantages of using one instead of the other?  And when do I choose one over the other?  

I would appreciate if you could provide simple examples to explain the differences.  

Many thanks.

Ed

PS.  There is a problem with Grid:-Seq as reported in one of my previous questions.