calculating specific weight I get an answer in kg/m²s². The context panel does not allow me to change the units to N/m³. Any suggestions how to change the units to N/m³. If I use Maple I get the right units. The problem is with Maple Flow.

How to find the dispersion relation (3) in Maple? I try it by equating the coefficients of cos(kx + wt) and its derivative to zero, but couldn't find it.

Download d_relation.mw

Hi everyone 

I have a problem regarding the animation of a flying ball. 

I get the coordinates and rotation in rad/s out of differential equations. Now I want to show the movement of the ball including the rotation in an animation. 

With just the coordinates it works just fine, but when I try do add the rotation the error message "number of elements in lust must be a multiple of 2" appears

I would be grateful for some advice. Thank you in advance.

I added my file, hope it helps.

how_rot.mw

Hi

My third-party soft is fussy: it will only accept pasted plaintext, with no spaces in between, for example:

1407,1411,2,1408,1409,0
1407,1408,2,1409,1411,0

#My input is 
ans1 := [1407, 1408, 2, 1409, 1411, 0], [1407, 1409, 2, 1408, 1411, 0], [1407, 1411, 2, 1408, 1409, 0];

#I am "trying" to remove the whitespace and convert it to plain text

with(StringTools):
for i to 3 do
seq(parse(DeleteSpace(convert(ans1[i][j],string))),j=1..6);
next i
od;

#But the whitespace is still there....

lprint(%%%);lprint(%%);lprint(%)
ans1 := [1407, 1408, 2, 1409, 1411, 0], 

  [1407, 1409, 2, 1408, 1411, 0], [1407, 1411, 2, 1408, 1409, 0]

                  1407, 1408, 2, 1409, 1411, 0

                  1407, 1409, 2, 1408, 1411, 0

                  1407, 1411, 2, 1408, 1409, 0

Dear all

My code give me the following error 
Error, (in SOR) invalid left hand side in assignment
I don't understand its origin.

coore_invalid.mw

Thank you

I'm working on finding the analytic expression of the PDF of a sum of abstract Uniform Random Variables URV).
Here "abstract" means that the supports are not numeric but litteral.

Maple is capable to find such a PDF for numeric supports but unable to determine the PDF of U1+U2 where 

U1 := RandomVariable(Uniform(a1, b1)):
U2 := RandomVariable(Uniform(a2, b2)):

A way to deal with abstract URV is to complute explicitely the convolution product of th PDFs.
Ir seems that this fails (MAPLE 2015.2) for these PDF are piecewise functions.
A workaround is to convert them first into Heaviside(s).

One done the explicit expression of the convolution product can be obtained for a sum of 2 abstract URVs, but not for a sum of a larger number of abstract URVs.

Thus the second workaround which consists in using direct and inverse Fourier transform.

The question is :
obviously, the PDF f(t ; a1...aN, b1...bN) of  U1 + ... + UN is a continuous function of t: why does discont(f(t ; ...), t) returns the non empty set of the values where the Heaviside functions are undefined ?

Here is a very simple result

u1 := RandomVariable(Uniform(-1, 1)): 
u2 := RandomVariable(Uniform(-1, 1)):
p := PDF(u1+u2, t):
discont(p, t);

print("-------------------------------------");

f1 := convert(PDF(u1, t), Heaviside):
f2 := convert(PDF(u2, t), Heaviside):
g1 := fourier(f1, t, xi):
g2 := fourier(f2, t, xi):
g  := g1*g2:
f  := invfourier(g, xi, t):
discont(f, t);

                               {}
            "-------------------------------------"
                           {-2, 0, 2}

The problem is (IMO) that discont(f, t) should return { }, but that some function (does it exists) should say that d is undefined at points t=-2, t=0, t=2.
The output of discont(f, t) doesn't seem consistent with the definition of the continuity

limit(f, t=-2, left);
limit(f, t=-2, right);
eval(f, t=-2)
                               0
                               0
                           undefined

Download Sum_of_Uniform_RVs.mw

Hello im an amateur using maple for my hidraulics machines course at engineering school. Does anyone know how to use the degrees package on maple 2022, i called it out by using the short form. with(Degrees): and then try to use sind but it doesnt recognice the command.

Also when using RPMs the units that should be giving me m/s appear as m²/m*s(radious). I know that the software recognice it as angular speed but is there anyway to eliminate the (radious) so i can work with the speed as lineal?

Please show me how to enter "positive infinity" value in the dialog box of "Maple Tutors". Thanks!i

Hi.  I am using the linux version of Maple.  I seem to experience more bombs in Maple/Linux vs MathCad/Windows.  The program just froze as I was entering text.  Just text.  It is not a disaster since I make very frequent saves.  But it is very annoying.  I was a heavy user of MathCad from about 2005 to 2019.  In the early days, it bombed a lot.  But I do not recall that it ever bombed when I was entering text.  Any suggestions?  Would there be a limition on the number of text characters?  Is it Linux?  Other than this problem, it is a great program.

I made an error by trying to multiply two nonconformable matrices. I think, I should receive an error message. But in this example this did not occur.

Strange.mw

Download Strange.mw

Hi! This is probably simple, but
I would like to know if there's an specific algorithm to do this:

let B =  in such a way that:

f( B ) = ; a_i in R; b_i in B; N>n.

so Linearcomb: f->V(R).

Linearcomb( f ) =

  + ... +.

with V(R) a vector space; R the Real numbers, and B the base. Neither the "factorize", nor the "simplify" are proving useful to this. Is there something i'm missng?

Please answer the commented questions in the uploaded worksheet.

Binary_search.mw

Hi everyone 

I have a problem with an animation that I dont know how to solve. 

Let's say I have three sets of coordinates. (one static and two moving dependet on time)

1:= [x1;z1]

2:= [x2(t);z2(t)]

3:= [x3(t);z3(t)]

Now I want out of these 3 points two lines that are connected  with each other like this:

line 1:= 1 and 2

line 2:= 2 and 3

These lines should move over time in the 2d space. The only point that doesnt move is point 1. In the animation there should only be the 2 lines visible for each frame. (not a trace or something like this) 

does anyone have an idea how I solve this?

Hi

I'm trying to automate this production of doubles combinations with a set scoreline in between. The minimum is 4 players, but we could have many more players, producing many combinations. 

example: 4 players, set score 2-0 for each match

with(combinat):
DBL:=choose([Novice,Weak_Intermediate,Strong_Intermediate,Advanced], 2);
DBL[1],2,DBL[6],0;DBL[2],2,DBL[5],0;DBL[3],2,DBL[4],0

#and the reverse
DBL[6],2,DBL[1],0;DBL[5],2,DBL[2],0;DBL[4],2,DBL[3],0
 

#the output contains square brackets. How do I remove them?

Does Maple Flow support the Maple Physics[Vectors] package? If so, how are vectors entered?