Hi, I need a little help please.

I'm writing some code that involves using solve() to solve some simultaneous equations and the output set from solve() is as follows :

{c[1] = 8/3, c[2] = 10/3}

I would now like to used the values 8/3, -10/3 in another calulation. However, I don't know how to extract the values/loose the variable parts of the set (namely "c[1]=" and "c[2]="). Can anyone help please.

FYI - I can't use fsolve as my simultaneous equations contain an another unknown variable, which I need to preserve.

Thanks in advance, Greg

On my PC I can't see the plus and minus sign in the quotient expression when using Student:-Basics:-LongDivision.

Is this a know display issue and is there to correct it?

Windows 10, Maple 2021.2

Download no_signs.mw

Thank you very much, Maple Community !

I have another (hopefully) easy question about a data set

seematrix_start_2_trim.xlsx

matrix_start_2_trim.pdf

I want to imitate Online Encyclopedia of Integer Sequences .b file

reference oeis.ort/A40

Cheers,

Matt

 I have two personal packages I wrote for Maple a few years age. I use them regurlary. They are stored in two differant locations.  Is there of interogerating Maple to find out where they are and some details obout them? What I load is

with(RationalTrigonometry) and with(RonanRoutines)

I finally found them again.

One in C\usersIRonan\Maple\persona\lib\RatTrig.mla

Other in (basically in) My documents\Maple\.A library\RonanRoutines1.mla

So the package load name and the .mla file name are different. I would like to know where the packages are being loaded from and under what name they are saved as.

The loglogplot procedure in the plots package labels the axes using "10 to the power notation" that looks like what you would see in LaTeX from the expresion "10^{-4}".

I"m at a loss about how to do the same.  If I try typesest(10^(-4)) the argument is converted to a rational before typeset gets the argument and the result is something equivlent to LaTeX's "\frac{1}{10000}".

Example:

    loglogplot(x, x = 0.1*10^(-5) .. 10, title = typeset(10^(-4)));

produces:

Dear all
I have an algorithm  to solve a first order odes, all steps of the algorithm ( as presented in the book are coded) but unfortunately something wrong. 
The algorithm and the code are attached in the following code. 
Thank you in advantage for your help. 

sol_odes.mw

I am a new user of Maple. I use Mathcad to plot n*n*n 3D mesh as shown in my sheet.

Please show me the way how to plot3D by Maple. I want to make f(n) to make n*n*n 3D mesh with points and lines.

Tokoro.

Hi again,

Are there any Maple experts out there that can help me save a matrix full of data?

two_column_matrix.pdf

Regards,

Matt

sum( (-1)^k/k * sin(k*x), k=-infinity..infinity);

  (mathematica solves this instantly.)

Hello friends, I have the following problem:
I have two lists of vectors, L1 and L2. The lists have the same number of vectors, and all the vectors have the same length.
I need to check if there is a permutation that, when applied to all the elements of one list, will obtain all the elements of the other list. For example, consider the following lists :

L1:=[<0|0|0>,<2|1|2>,<1|2|1>];
L2:=[<1|1|2>,<2|2|1>,<0|0|0>];

In this example the vectors are of length 3. Therefore, there are 3!=6 possible permutations. Namely:

P1:=<<1,0,0>|<0,1,0>|<0,0,1>>;
P2:=<<0,1,0>|<0,0,1>|<1,0,0>>;
P3:=<<0,0,1>|<1,0,0>|<0,1,0>>;
P4:=<<0,0,1>|<0,1,0>|<1,0,0>>;
P5:=<<0,1,0>|<1,0,0>|<0,0,1>>;
P6:=<<1,0,0>|<0,0,1>|<0,1,0>>;

In this case there are two permutations that satisfy the condition above, namely:

P3:=<<0,0,1>|<1,0,0>|<0,1,0>>;
P6:=<<1,0,0>|<0,0,1>|<0,1,0>>;

Cause

for i in L1 do Multiply(i, P3) end do;
>[0 0 0]
  [2 2 1]
  [1 1 2]
 
The same result is obtained using the permutation P6.
I'm working with larger lists and longer vectors so I'm looking for a quick way to check this. Thanks for your valuable help.

Maple users may notice unexpected results when calculating standard deviations with weights.

This is because the notion of weights used by Maple is not exactly the commonly used notion of repeated measurements.

Maple uses the NAG library from the Numerical Algorithms Group to compute the standard deviation in the presence of weights. The formula that is used is given in their documentation: https://www.nag.com/numeric/cl/nagdoc_cl25/pdf/g01/g01aac.pdf.

Download standard-deviation-weights-help-example.mw

Hello,

I am trying to solve the following system of odes where the unknowns are xhat, yhat, uhat and vhat. They depend on the variables (x, y, u, v, a_1, a_2, a_3, a_4, f(x)) where f(x) is an arbitrary function and I want to solve it with respect to a_1. The RHS has f(x) and its derivative with respect to x. The dsolve function fails to solve the ode when I add f(x) at the list of variables. 

restart;
vars := x, y, u, v, a_1, a_2, a_3, a_4, f(x);
sys_ode := diff(xhat(vars), a_1) = a_3*x + a_1, diff(yhat(vars), a_1) = a_2 - a_4*y + f(x), diff(uhat(vars), a_1) = a_3*u + 2*a_4*u, diff(vhat(vars), a_1) = a_4*v + diff(f(x), x)*u;

initvars := x, y, u, v, 0, a_2, a_3, a_4, f(x);
ics := xhat(initvars) = x, yhat(initvars) = y, uhat(initvars) = u, vhat(initvars) = v;
solution_a1 = dsolve([sys_ode, ics], [xhat, yhat, uhat, vhat]);

Can anyone help regarding this issue ?

Hello dear experts. Please help me with a specific issue.
There is an article (attached A_Fuzzy_Best_Worst_approach_to_the_determination_of_the_importance_level_of_digital_supply_chain_on_sustainability.pdf) that describes the Fuzzy Best Worst method for solving a specific problem. On page 7, in the description “Step 5”, it is indicated that the calculation of the equation takes place in the Maple software. As a result, they receive fuzzy criteria weights.

Also on page 9, at the very top, the model itself is described, which is used in Maple.

Please tell me how these fuzzy criteria weights are calculated in Maple? Thanks in advance.

Anyone could help me know how to use of "Back Solving Assistant", please? I can't understand how to enter a formular. When I enter a formula, even the one suggested by Maple, and then click the "Proceed to Back-Solver" button, I always get an error message. Please help me!

how can i Roand my answers to 2 number after decimal point.

That is, Maple shows me only two digits after the decimal point. like this. 

with(LinearAlgebra);
K := evalf(Matrix(3, [1/3, -20/3, -20/3, 200/3, 70000/3, 4000/3, 1.44]), 6);