Good night.

I have a problem with this error "Error, (in unknown) invalid input: `dsolve/numeric/lexorder` expects its 2nd argument, b, to be of type {indexed, name, numeric}, but received cos(t) "

help me please

final-robot-circul.mw

Hey,

I have one function that is consisted of several matrices.. The function is,

R := log(determinant(MCOV))+trace(multiply(SCOV, inverse(MCOV)))-log(det(SCOV))-2+Transpose(SM-TAU-multiply(L,K))&*inverse(MCOV)&*(SM-TAU-multiply (L, K));

where MCOV, SCOV, SM,TAU, L, K are all matrics. In a MCOV and L, there are symbols also..

I have tried to get...

Dear Mapleprimes,

I have a problem with the sum command. I'm differentiating wrt. a value q[i] in a sum. I have the following:

diff(sum((1/2)q[i], i=1..n),q[i]);

This returns:

n(1/2)

but I'm differentiating wrt. q[i] not the whole sum. Any ideas?

Thanks very much.

Christian

Hi, I have 2 sets of data:

P := array([1.23, 1.15, 1.10, 1.20, 1.35, 1.25, 1.28, .99, 1.22, 1.25, 1.30, 1.05]);

Q := array([892, 1012, 1060, 987, 680, 739, 809, 1275, 946, 874, 720, 1096]);

p=P(t), q=Q(t) i.e. both p & q are a function of parameter t  t=1..12

2 functions: 

x=ln(p)

y=ln(q)

I'm trying to display x against y , ie x=ln(p) on the horizontal axis, y=ln(q) on the vertical

Dear Mapleprimes,

I'm trying to add a sequence of numbers using the add command. It appears that it can only add up to a specific number. The following works:

add(2*i, i=1..5)

gives 30.

But it is not possible to do:

add(2*i, i=1..n)

such that n is a parameter.

Does anyone know how to add a finite series of values where n is unknown?

Is there a way to change the default settings for ArrayTools[RandomArray](distribution= )  ?

There are two distribution values available uniform, which is on the unit interval and normal which draws from a normal distribution on the unit interval. 

Can we modify those settings?  Such that using distribution=uniform (or normal) is forced to some user setting outside the unit interval?

Unable to open these maple files, please help

I have a question in Maple TA that is asking for an answer in radians, and when I post the answer that I get it does not accept it...I'm assuming I'm doing the problem correctly, but my answer is not in the correct format.

How to speedup them? There are more than 20 functions that are evaluated one by one. Is option 'remember' + permanent remembered item of pure symbolic calculation can speedup this process? How also efficiently to do simlify itself? Can i actually use more kernels in one session or to paralilize available one?

Hello everyone

I have a function, constructed by numerically solving a set of differential equations.  I need to find a best fit for this function with an analitic model with two parameters. I tried to extract some points of this function and then using nonlinearfit:

xvalues:=Vector([seq(10⁵ ..10⁶,10⁴);

yvalues:=Vector([seq(evalf(function),x=10⁵ ..10⁶,10⁴)]);

with(Statistics):

Hello,

I have a derivation to do for my PhD thesis, and it is long and tedious. It is essentially a case of splitting sums, making substitutions and then simplifying. I believe maple can do this for me, but have not found how yet. Any suggestions would be more than welcome. I have done this for a third order problem (three nested sums) and the derivation runs to many pages. I now need to do so for the 4th order problem, and it is a more than daunting prospect

In polar coordinate, when we differentiate e_r, it becomes e[theta]. However it seems Maple can't do this, even I have set it into polar coordinate.

How can I allow maple to do this?

Any Example can help see the difference between contour and simple integration?

int(XXXX, x, method = contour);

int (XXX, x)

which example can help to see the difference?

Why that Find / Replace doesn't work?

Wnat to rename some variables but it doesn't seem to find text in eval-cells at all :(

hi

I wan`t use maple to solve my problem

x₁[n]= e^{j*( Π/6) *n}