Dear All,

I am trying to formulate and solve a linear system of equations to determine the 15 unknowns (link to the script below.) The funcion solve does not seem to return a vlaue due to the lengthy and complex nature of the equations neither do linsolve or LinearSolve. I am wondering whether there exists an argument of another trick that can be employed in order to tackle with such complicated systems. Any help or hint is highly appreciated and desirable.

Thank you,

Bests

Federiko script: SolveLinearSystem.mw

I have a functional equation in 2 variables, and I want to write its solution(s) as (Puiseux) power series. When the order is relatively big, the output appears not in the increasing order of powers. For example, I execute 

map(allvalues, algeqtoseries(P, t, u, 60, true))

and get as one of the solutions

O(t^(65/3)) + 13*t^9*(1/3) + 2*t^5*(1/3) + 115*t^15 + 37*t^13 + 5*t^7*(1/3) + 37*t^11*(1/3) + (1/3)*t^3 + 11836*t^21*(1/3) + 1193*t^19 + 1100*t^17*(1/3) [...]

What should I do in order to get the series with terms appearing in the increasing order of powers of t?

Thanks!

Maple will multiply two matrices for me perfectly.  

However, when I change the value in one of the cells and try to re-evaluate the product, Maple starts giving me the sum of something in all of my cells.   

Are you simply not allowed to ever change the initial values you set for a matrix?  This doesn't seem to make sense to me.  

I have attached a screen shot to show an example with a random matrix.  

Dear Maple users,

I recently had to deal with the following sum :

sum(binomial(k+i,k),i=0..infinity)

for an arbitrary positive value of k. This sum obviously seems to diverge but Maple gives me 0 as a result for it. It looks very strange to me, but it might be the same sort of result as the sum of all the positive integers is -1/12. I am wondering whether the result Maple gives me is correct, and if yes, where does it come from ?

Any idea ?

Thanks a lot!

for example i have this equation: y=x+c , y and x are variable, but c is constant. i want to plot implicitly with respect to y and x, but the result has no line or something and just two axes. what can i do?

If I have 4 latitude and longitude coordinates in degree.  How can I convert all of them to radian and assign each to a specific variable inside a procedure?

>

> DBP(36.9,102.04,37.345,101.6104)
Error, invalid loop statement termination

attached: WA57dev.mw

is(k::OrProp(even, odd)) assuming k::integer;
                             false

is(k::Or(posint, nonposint)) assuming k::integer; # a synonym for OrProp
                             false

is(`or`(k::posint, k::negint, k = 0)) assuming k::integer;
                             false

Not including the infix or because that would fail for k=0 for different reasons.

Hey, friends, I have a differential equation to confuse me too much!  The question is shown in the below:

ODEs:

y''(x)-0.00003019*y(x)^0.337=0  ,       0<x<2945

BCs:

y(0)=0,    y'(2945)=0.0116 

I want to have the numerical solution, I used to plot y(x) and y'(x) , but errors shows me "jacobian is singular at left endpoint, use midpoint method instead."  Thank you for you any help in advance!!!  

Can you give me the code to figure it out in Maple?  Thank you so so so so much!

1.

eliminate({-a+x+y+z, -b+x*y+y*z+x*z, -c+x*y*z, -P+x^4+y^4+z^4}, {x, y, z});
    [{x = (sqrt(c^2*(a^2*b^2-2*a*b*c-4*b^3+c^2)/b^4)*b^2+a*b*c-c^2)/(2*b*c),
      y = -(sqrt(c^2*(a^2*b^2-2*a*b*c-4*b^3+c^2)/b^4)*b^2-a*b*c+c^2)/(2*b*c),
      z = c/b}, {-a^4+4*a^2*b-4*a*c-2*b^2+P}],
    [{x = -(sqrt(c^2*(a^2*b^2-2*a*b*c-4*b^3+c^2)/b^4)*b^2-a*b*c+c^2)/(2*b*c),
      y = (sqrt(c^2*(a^2*b^2-2*a*b*c-4*b^3+c^2)/b^4)*b^2+a*b*c-c^2)/(2*b*c),
      z = c/b}, {-a^4+4*a^2*b-4*a*c-2*b^2+P}]

The expression for P is fine, but how are x and y square roots and z=c/b??

2.

eliminate({y*z, x+y-z}, z);
                       [{z = 0}, {x + y}]

Is this supposed to happen? I was expecting y*(x+y):

Groebner:-Basis({y*z, x+y-z}, lexdeg([z], [x, y]));
                     [x*y + y^2, z - x - y]

I have to fit two lists of data to a function of the type A*sin(bx+c)+d, but when I do (actual data):

X := [seq(i, i = 0 .. 24)];
Y := [1154, 1156, 1156, 1155, 1152, 1143, 1105, 1069, 1051, 1077, 1117, 1154, 1154, 1156, 1158, 1157, 1155, 1152, 1128, 1089, 1058, 1059, 1092, 1130, 1163];

with(Statistics):

f:=Fit(A*sin(b*x+c)+d, X, Y, x);
plot({f(x), [seq([X[i], Y[i]], i = 1 .. 25)]}, x = 0 .. 24, style = [line, point])

They match up very poorly. I can get a better fit by using Geogebra (which produces a function 48.7 * sin(0.52x + 0.56) + 1124.95, which fits the data much better).

I can get a good fit using CurveFitting[Interactive], but the resulting function doesn't fit my target format. What can I do to get a better fit in Maple while staying within the target format?

Hi, I am currently using the embedded components to make an interface in maple 2016. However, when I executed the startup code, an error was reported, which is 0, "recursive assignment". The recursions are not allowed in the startup code? Anyone can help me with this problem? By the way, how to cancel the warning of executing the startup code when I open the .mw?

Many thanks!

Is the smallest unit of time that Maple can use to report the computation time millisecond? When I use time(...) the output is a floating-point number with at most three digits after the floating point and since the unit in Maple help is said to be seconds, I'm thinking the smallest time unit it will report is millisecond. Is there any possibility to have more digits in the time reports, let's say up to 10^-5 seconds?

How to most effectively generate all matrices from zeros and ones (matrices size 6 by 6), such that in each row and in each column exactly 4 units. This problem was encountered in solving one problem in the field of entertaining mathematics. I know how to solve it in about 100 seconds, but I so far do not give my solution so that everyone can enjoy solving it.

My "for loop" index is being treated as a letter and not a number. The 'h' in my for loop is is supposed to be the index for these tables but the result is tables that have indices of the letter 'h'.  

The indexing for the 'Z' part works Z[h][1] ,Z[h][2] and Z[h][3] have numbers instead of the letter 'h' but the x1[h], y1[h] and Q[h][1],Q[h][2] and Q[h][3] are all 'h' indexed with no number as an index when I view this table in the variable viewer.

for h to 50 do :

Z[h][1] := s -> evalf(subs(x = x1[h](s), y = y1[h](s), Q[h][1])) ;

Z[h][2] := s -> evalf(subs(x = x1[h](s), y = y1[h](s), Q[h][2]));

Z[h][3] := s -> evalf(subs(x = x1[h](s), y = y1[h](s), Q[h][3])); 

end do:

the result is just using the last value of index 'h' and puting it in the first index of 'Q'. There is nothing defined with index 51.

Z[2][3](4*(1/50));
                            Q[51][3]
Z[9][3](4*(1/50));
                            Q[51][3]
 

if I hard code the index numbers then it works correctly but I do not want to hard code all 50 of these.  

Why is the for loop index variable 'h' treated as a letter and not evaluated to be a number in the indexing?

thanks . . .