Units seem to be interfering with elementwise square roots.  I have with(Units[Standard]): in my .mapleprofile since I frequently use units.  I am working on a document which uses units but also requires computing the elementwise square root of a 2x1 vector.

If I boil this down to the very simple document attached, you can see that the units package is somehow interfering with the square root of a vector of numbers without units, but doing an elementwise square root doesn't work either.  I have tried removing the with(Units[Standard]): line in the startup file for this document and recomputing, but nothing changes.

I don't see how to do elementwise square roots in this situation.  Is there a workaround, or am I missing something?

Thanks,

Gerrit

Elementwise_Square_Root.mw

Does anyone know how the sum command works? If I set

f:=proc(x) if x<=1 then 1 else 2

then compute

sum(f(i),i=1..10)

I get an error, as it tries to check "i<=0", for the symbol 'i'. Curiously if the comparison in 'f' is "x=1" it goes through fine. Another place this comes up is using "op" on lists. If I set

z:=[[1,2],[3,4],[5,6]]

then compute

sum(foldl((x,y)->x*vars[y],1,op(z[i])),i =1..3)

it doesn't give the desired answer. When i=1 for example, I think it computes op(z[i]) as op(z[i])->i->1, rather than op(z[i])->op(z[1])->op([1,2])->1,2.

Hello Guys,

Can maple derive Einstein field equations from Einstein-Hilbert action ?

Thx

hello guys, I can't take the real part of this formula that you can see in the picture that I upload for you.
please help me!!!!!!!!
sorry for uploading photo...so surry

I want to see that if parameter 'alpha' tends to the infinity amount of parameter 'p' how changes?

how I can see and do  this process?

thanks

_nahaii.mw
 

Download _nahaii.mw

Hi every body:

I want to solve these equations with maple, can everyone help me how to solve them?

eq1 := diff(u1(x), x, x)+diff(u2(x), x)+int(2*x*s*(u1(s)-3*u2(s)), s = 0 .. 1) = 6*x^2+3*x*(1/10)+8
eq2 := diff(u1(x), x)+diff(u2(x), x, x)+int((3*(s^2+2*x))*(u1(s)-2*u2(s)), s = 0 .. 1) = 21*x+4/5
bcs := u1(0)+(D(u1))(0) = 1, u2(0)+(D(u2))(0) = 1, u1(1)+(D(u1))(1) = 10, u2(1)+(D(u2))(1) = 7

with regards...

I want to plot these in one frame:

between [0, 0.2]

between [0.2, 0.4]

betwen [0.4,0.6]

between [0.6, 0.8]

I want to plot all these functions y[0], y[1], y[2], y[3] in one plot between the mentioned interval.

I am trying to find numerically eigevalues and eigenvectors of a 70x70 matrix. When I type

Eigenvalues(M70, output = 'list');

Maple returns the matrix M70 without processing it. I have also tried Determinant, Gaussian elimination and other - the same story. However, Maple has no problem inverting this matrix numerically. Everything also works well for 20x20 matrix but not for 70x70 one.  70x70 is not such a big matrix. It should be doable.

What is the solution? Do I do something wrong?

I've tried every which way to get the Bezier Curves task to work.  I have embedded it in an existing document and in a new one using Tools / Tasks / Bezier Curves, and it doesn't work at all for me.  Sometimes I get errors when I click Initialize (not always), and I never get any reaction from clicking or dragging in the plot.  Is this me or the task?

I also can't see any of the inner workings of the task.  I don't see how the slider connects to the n variable, or how the plot is generated, or where the plot points come from.  Therefore I can't see how to customize the task for my use.

I've seen other Maple documents like this in Help, too.  How do I see and modify the inner workings of these documents?

Below is an attempt to evaluate an integral from t to ZERO.  I believe the issue is that sin(x) in the denominator is causing a problem.  However, in actuality sin(nx) is in the numerator so at the lower integral bound approaching ZERO the factor of n remains.  So how can I get MAPLE to evaluate this correctly?
 

Download evaluating_integral.mw

Hello,

I'm trying to evaluate an integral (code snippet and screen-shot included below) assuming that certain parameters and integers. Using assume statements the integral evaluates to 0. However, if I evaluate the integral for a specific set of integers, the integral evaluates as non-zero.

Can anyone clarify why the two int statements return different values?

Thanks!

assume(K::integer);
assume(L::integer);
assume(M::integer);
int(sin(K*x)*sin(L*x)*cos(M*x), x = 0 .. Pi);
     returns: 0
int(sin(14*x)*sin(2*x)*cos(12*x), x = 0 .. Pi);
     returns: Pi/4

I have the following maple code. 

R11 := x -> (x+2*a_1)*(product(x+b[j], j = 1 .. k-n))/(x+a_1);

T_4 :=  (z_1, z_2, z_3, z_4) -> R11(z_1)*z_2*z_3*z_4;

%*(z_1+a_1);

I would like maple to simplify (z_1+a_1) in the denominator of R11(z_1) with the (z_1+a_1) from the last line, but it does not do that. Simplify command also does not help.

I am trying to learn how to use the Physics tensor routines by using a simple 2D example.  In the following, I set up the Cartesian Euclidean metric tensor and then tried to transform to cylindrical coordinates.  The metric tensor is correctly transformed in line (5), but then when it is called in line (7), it still has Cartesian values.  What am I doing wrong?

with(LinearAlgebra);
DotProduct([a, b], [c, d]);

gives

Does it think that I want my variables complex conjugated? (And why?) How do i turn it off?

Hello.
I can not find a tool for calculating the number of permutations with fixed points. I looked at the package combinat. Help me please.