f1 := 0.001;
f2 := 0.002;
c1 := 0.002;
c2 := 0.005;
w1 := 0.1;
W := 0.14;
p1 := 0.65;
p2 := 0.28;
p := 1.167;
r := 0.004;
alpha := 0.2;
ze := 0.14;
mu := 0.05;
ga := 0.01;
cp := 9.3;
Rp := 100;
sigma2 := 0;
l[1] := 3*W^2*(-1+W^2)/(4*(-1+4*W^2));
l[2] := Rp^2*w1^2*mu*ga*cp/(2*(Rp^2*w1^2*cp^2+1));
l[3] := (Rp.w1.mu.ga)/(2*(Rp^2*w1^2*cp^2+1));
l[4] := W*(-1-7*W^2+8*W^4)/(8*(-2+8*W^2));
eq1 := (-x*t+l[2]*x+l[1]*x*y^2+(3/2)*alpha*ze^2*x)^2+((1/2)*c1*x+l[3]*x)^2-(1/4)*f1^2;
eq2 := (-l[4]*y^3+l[1]*x^2*y)^2+(1/4)*y^2*c2^2-f2^2/(4*W^2);

I need to solve these two equation for the variable x and y in terms of  t because I want to plot x with a range for t 

and the same plot y with a range for t and if it is possible to plot x vs y for the previuos same range for t

ode.mw

I found an assignment question concerning an ODE from 20 years ago. This was before I had discovered Maple.

So I put it through Maple and got a complex solution, But the lecturer's solution was non-imaginary.

For a) gamma <> Beta and b) gamma = beta.

Actually for b) I couldn't follow his solution

Consider

restart;
L := [1,2,3,4];
x[j];
seq(%, x[j] in L);
x[j];

What would you expect the output of the last line to be?

Answer:   Maple says 4.   Why?

We have just released an update to Maple, Maple 2020.1.

Maple 2020.1 includes corrections and improvement to the mathematics engine, export to PDF, MATLAB connectivity, support for Ubuntu 20.04, and more.  We recommend that all Maple 2020 users install these updates.

This update is available through Tools>Check for Updates in Maple, and is also available from our website on the Maple 2020.1 download page, where you can also find more details.

In particular, please note that this update includes a fix to the SMTLIB problem reported on MaplePrimes. Thanks for the feedback!

Hi, 

In Maple it's possible to say that some quantity x has a value of 1 and that its unit is the meter (for instance).
But is it possible to say that x is a quantity whose fundamental unit is the 'length' (or any other fundamental unit, I insist on this point: I don't want to use derived units such as 'force', 'speed', ...)?

I think that the Units package doesn't allow to do this (or maybe I didn't figure out how).

Do you have any suggestions about that?

TIA

This is my notebook

I don't understand why computing the wedge product of two differential forms gives me an output which prints the product of both. Why  don't it just return d rho ^ dt?

Hi Everyone, So i have a pretty ugly function which i am interesting in plotting. When i plot it seems that all values are real however when i do evalf with specific values of variable i am plotting over it shows that it is complex. Any thoughts on how to get it to stop plotting once it becomes complex? See attached maple file.

ComplexPlotQuestion.mw

Thanks. 

Monte Carlo integration uses random sampling unlike classical techniques like the trapezoidal or Simpson's rule in evaluating the integration numerically.

Download MONTE_CARLO_INTEGRATION1.mw

1. Plot the solid that lies between the cone z=(x^2+y^2)^(1/2) and the plane z = 4.

2. Plot the solid that lies above the cone z=(x^2+y^2)^(1/2)  and below the sphere z=x^2+y^2+z^2.

3. Plot the solid that is inside the hemisphere z=sqrt(25-x^2-y^2) , outside the cylinder x^2+y^2 = 4 and above the plane xy − plane.

4. Plot the solid bounded by the hemisphere z=sqrt(16-x^2-y^2)and the paraboloid z=x^2+y^2.

5. Plot the solid that lies within the sphere x^2+y^2_z^2=4 , above the xy − plane and below the cone z=sqrt(x^2+y^2).

This proc is valid, yet Maple mint thinks there is syntax error

foo:= proc(x)
local z := "";
    if not x in ["A","B"] then
        return;
    fi;

    z:=cat("A
            B");    
end proc;

mint t.mpl gives

on line     7:     z:=cat("A
                          ^ Syntax error
A "then" was found without a previous matching "if".
An "end" may be needed to close the "in" construct from line 3.

But these two below procs below it gives no syntax error

foo:= proc(x)
local z := "";
    if not x in ["A","B"] then
        return;
    fi;  
end proc;

And

foo:= proc(x)
local z := "";
    z:=cat("A
            B");    
end proc;

No syntax error on either one. the syntax error only shows up when combining them. 

What does if not x in ["A","B"] then  have to do with the cat  below it? And why when they are combined, the syntax error shows?

I know of workaround, such as changing the cat to  z:=cat("A\nB");     or keep the strings on two lines, but do it like this

    z:=cat("A\n
           B");

Or write it like this

   z:=cat("A "
           "B"); 

But none of these changes were needed before adding the not x in ["A","B"]  before.

Is this a bug in mint? Is there a work around so the first example above still works using 

    z:=cat("A
            B");   

?

Hi,

I didn't use Maple before, I want to use it in this problem 

How to get the displacement equation of the longitudinal vibration of rod (bar) when the boundary and initial conditions are 

Dear Maple Users @acer @Carl Love @Kitonum @Preben Alsholm ,

Greetings.

How to plot a function "Am" for various values of "kt"(eg: kt=-1..1) at a point x=0.

Am vs kt.

The code has provided below.

Waiting for your response.

ktplot.mw

The purpose of this document is:

a) to correct the physics that was used in the document "Minimal Road Radius for Highway Superelevation" recently submitted to the Maple Applications Center;

b) to confirm the values found in the manual for the American Association of State Highway and Transportation Officials (AASHTO) that engineers use to design and build these banked curves are physically sound. 

c) to highlight the pedagogical value inherent in the Maple language to distinguish between assignment ( := )  and equivalence (  =  );

d) but most importantly, to demonstrate the pedagogical value Maple has in thinking about solving a problem involving a physical process. Given Maple's symbolic mathematics capabilities, one can implement a top-down approach to the physics and the mathematics, working from the general principle to the specific example. This allows one to avoid the types of errors that occur when translating the problem into a bottom up approach, from specific values of the example to the general principle, an approach that is required by most other computational systems.

I hope that others are willing to continue to engage in discussions related to the pedagogical value of Maple beyond mathematics.

I was asked to post this document to both here and the Maple Applications Center

[Document edited for typos.]

Minimum_Road_Radius.mw

Hallo;
the following MAPLE code generates 2-vectors. To collect them into a set K unfortunately does not work. K contains vectors two-fold etc. So K is not a set which I hoped to get. What is wrong?

restart:m:=5;#m Module
with(LinearAlgebra[Modular]):
K:={};
M:=Matrix([[3, 4*168], [4,3]]);
L:=Matrix([[3],[4]]);
#with(LinearAlgebra[Modular]):
for s from 0 to 10 do
a:=Mod(m,(M^s).L,integer);
K:=K union {a};
od:
K:=K;

Gerd

Hi experts

with(plots):
#epsilon:=5*Pi/2:
gammaa:=0.4:
gammao:=0.1:
gammab:=0.002:
omegab:=100:
X:=60:
Omega:=6*Pi:
g:=10:
sigmag:=5*gammaa:
a:=1/(sigmag*sqrt(2*Pi)):

#deltao:=1:
D7:=evalf(a*int(g*Omega*(gammao/2-I*Delta)*exp(-0.5*((Delta-deltao)/sigmag)^2)/(gammao^2/4+Delta^2),Delta=-infinity..infinity)):
D8:=evalf(0.5*a*int(g^2*gammao*exp(-0.5*((Delta-deltao)/sigmag)^2)/(gammao^2/4+Delta^2), Delta=-infinity..infinity)):
D9:=evalf(a*int(g^2*Delta*exp(-0.5*((Delta-deltao)/sigmag)^2)/(gammao^2/4+Delta^2), Delta=-infinity..infinity)):
b1 := (deltao-2*X^2*omegab*Y/(gammab^2+omegab^2)-D9)^2:

 f:=Y*((gammaa+D8)^2+(b1))=Im(D7)^2+(epsilon-Re(D7))^2:
#P1:=implicitplot(f,deltao=-70..50,Y=0..1,numpoints=100,axes=boxed,thickness=2,color=black,font=[1,1,20],tickmarks=[4, 3],linestyle=1);

implicitplot3d(f,Y = 0 .. 1,deltao=-40..40,epsilon=0..0.4,numpoints=100,labels=[Y,deltao,E],tickmarks=[3,3,3], style = surface, color = "Niagara Azure");

The above code to plot the implicitplot3d ,

first the figures are not smooth

second thing is how to make contourplot at epsilon= 5*Pi/2.

I appreciated any comments