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Hi

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

 

wz

How to animete BC using varying temperature in time?  How to obtain animated solution?

restart

Diffusivity coefficent...

a := 0.1e-5:

Thickness of barrier...

L := .2:

Heating curve:
Time in heating curve (in hours form exmaple)...

Time := seq(i, i = 1 .. 10):

Varying temperature in time [K]....

Temp_in_Time := [433.15, 568.15, 703.15, 838.15, 973.15, 1108.15, 1243.15, 1378.15, 1513.15, 1616.15]:

Initial temperature [K]

Tot := 298:

PDE := diff(T(x, t), t) = a*(diff(T(x, t), x, x)):

--->>>

BC1 := {T(0, t) = Temp_in_Time[2], T(L, t) = Temp_in_Time[2], T(x, 0) = Tot}:

sol := pdsolve(PDE, BC1, numeric, timestep = 50):

sol:-plot(t = 3*3600, thickness = 3, colour = red);

 

``



Download heating.mw

Hi

 

I have some data:

Matrix(10, 2, {(1, 1) = 0, (1, 2) = 0, (2, 1) = .5, (2, 2) = 3.25, (3, 1) = 1.0, (3, 2) = 5.82, (4, 1) = 1.5, (4, 2) = 7.50, (5, 1) = 2.0, (5, 2) = 8.79, (6, 1) = 2.5, (6, 2) = 9.83, (7, 1) = 3.0, (7, 2) = 10.66, (8, 1) = 3.5, (8, 2) = 11.35, (9, 1) = 4.0, (9, 2) = 11.94, (10, 1) = 4.5, (10, 2) = 12.46})

 

I want Maple to make a trendline fitting a Logarithmic function. I can make it output some function with this:

LeastSquares(`<,>`(.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5), `<,>`(3.25, 5.82, 7.50, 8.79, 9.83, 10.66, 11.35, 11.94, 12.46), x, curve = a+b*ln(x))

It outputs:

5.96497783539274+4.25309474196387*ln(x)

 

But please notice, the dataset in the function does not have the first 0 and 0. If i do that:

LeastSquares(`<,>`(0, .5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5), `<,>`(0, 3.25, 5.82, 7.50, 8.79, 9.83, 10.66, 11.35, 11.94, 12.46), x, curve = a+b*ln(x))

It outputs: 

Error, (in Matrix) numeric exception: division by zero

 

Besides that, i need the R-squard value for determinating how well it fits.

 

If i do the same thing i Excel the data set will give a formular: 5.5464ln(x)-0.2175 with a R-sward value of 0.9985.

 

How can i do this i maple?

 

Thanks in Advance!

 

----

Emil Kristensen

Thank you for your help with this question. I found what I was looking for. 

Dear all

I would like to convert Matlab code to Maple, is there anu idea, this is the code.

 

% Usage: [y t] = abm4(f,a,b,ya,n) or y = abm4(f,a,b,ya,n)
% Adams-Bashforth-Moulton 4-th order predictor-corrector method for initial value problems
% It uses
% Adams-Bashforth 4-step method as a precdictor,
% Adams-Moulton 3-step method as a corrector, and
% Runge-Kutta method of order 4 as a starter
%
% Input:
% f - Matlab inline function f(t,y)
% a,b - interval
% ya - initial condition
% n - number of subintervals (panels)
%
% Output:
% y - computed solution
% t - time steps
%
% Examples:
% [y t]=abm4(@myfunc,0,1,1,10);          here 'myfunc' is a user-defined function in M-file
% y=abm4(inline('sin(y*t)','t','y'),0,1,1,10);
% f=inline('sin(y(1))-cos(y(2))','t','y');
% y=abm4(f,0,1,1,10);

function [y t] = abm4(f,a,b,ya,n)
h = (b - a) / n;
h24 = h / 24;

y(1,:) = ya;
t(1) = a;

m = min(3,n);

for i = 1 : m % start-up phase, using Runge-Kutta of order 4
    t(i+1) = t(i) + h;
    s(i,:) = f(t(i), y(i,:));
    s2 = f(t(i) + h / 2, y(i,:) + s(i,:) * h /2);
    s3 = f(t(i) + h / 2, y(i,:) + s2 * h /2);
    s4 = f(t(i+1), y(i,:) + s3 * h);
    y(i+1,:) = y(i,:) + (s(i,:) + s2+s2 + s3+s3 + s4) * h / 6;
end;

for i = m + 1 : n % main phase
    s(i,:) = f(t(i), y(i,:));
    y(i+1,:) = y(i,:) + (55 * s(i,:) - 59 * s(i-1,:) + 37 * s(i-2,:) - 9 * s(i-3,:)) * h24; % predictor
    t(i+1) = t(i) + h;
    y(i+1,:) = y(i,:) + (9 * f(t(i+1), y(i+1,:)) + 19 * s(i,:) - 5 * s(i-1,:) + s(i-2,:)) * h24; % corrector
end;

Dear people being here,

I have a question.

When I wrote as

aa:=(delta[1]*n[1])/(n[f1]*delta[1]);

maple returned as 

aa := n[1]/n[f1]

How can I have maple express the original one, aa:=(delta[1]*n[1])/(n[f1]*delta[1]), not what returned to me?

I hope you will answer to my question.

And, thanks in advance.

 

taro

I am to program a computation on maple.
But I get the message :

Error, unable to match delimiters

followed by the full sequence of command.

 

How can I do to fix this problem?

Can someone explain to me, if you can, how the Euler angles on the plot interface work?

 

It looks like Phi is the rotation around z, Theta is the rotation around x, and Psi is around y. I'm trying to use matrices to compute the vector that is pointing towards your face as you're looking at the plot with the given Euler angles.


X := Matrix(3, 3, {(1, 1) = 1, (1, 2) = 0, (1, 3) = 0, (2, 1) = 0, (2, 2) = cos(phi), (2, 3) = sin(phi), (3, 1) = 0, (3, 2) = -sin(phi), (3, 3) = cos(phi)});


Y := Matrix(3, 3, {(1, 1) = cos(theta), (1, 2) = 0, (1, 3) = sin(theta), (2, 1) = 0, (2, 2) = 1, (2, 3) = 0, (3, 1) = -sin(theta), (3, 2) = 0, (3, 3) = cos(theta)});


Z := Matrix(3, 3, {(1, 1) = cos(psi), (1, 2) = sin(psi), (1, 3) = 0, (2, 1) = -sin(psi), (2, 2) = cos(psi), (2, 3) = 0, (3, 1) = 0, (3, 2) = 0, (3, 3) = 1});

and computing X*Y*Z*e3

 

TIA!

i interpolate a function in some knots by BSplineCurve, the resulting function is parametric.

how i can convert this parametric function to a function?

thanks.

((x-6.05)/sqrt(.0004/9) < (6.035-6.05)/sqrt(.0004/9))

Maple comes up with P(150.000000000x<905.2500000), but I cant get Maple to tell me

P(Z<-2.25).. How can I get it to calculate and tell me to use Z tables ?

Twenty five observations of a random variable X are :130.8  129.9  131.5  131.2  129.5  132.2  133.7  127.8  131.5  132.7  134.8 131.7  133.9  129.8  131.4  132.8  132.7  128.8  130.6  131.1  133.8  130.5 131.4  131.3  129.5  //.. How do I construct a stem and leaf display using stems of 127, 128, 129, ... 134? I also need to find all quartiles.. Thank you to anyone...

If Z is N(0,1) find

a) P(0<=Z<=.87)

I understand how to get to 0-0/1<=Z-0/1<=.87-0/1

which ends up being OI(.87), but am not sure how to get this to calculate. Plus I ant use proper functions here becuase I dont have the pallette, but OI is an O with the I through it... Φ(.87) I beleive....

I dont know how to have Maple calculate ths to give me the correct normal distribution value.

How do I find the vertical asymptote of tan(x) when x=x/x+1?

I need to draw a box plot (BoxPlot(X,title="Box Plot", color=red) that shows the outliers, suspected outliers and fences. Can anyone direct me? Thanks.

Anybody has a hint on how to solve a non-linear system with trigonometrics. I want to solve x, y and z.

 

a)can someone pls help write code to generate this circle within square, then square within circle....(with the colours) 

figure.doc

Its a bit like this problem:

http://www.mapleprimes.com/questions/141883...

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