MaplePrimes Questions

The map[inplace] operation can apply a function to the elements of an rtable, replacing these elements with the result.  Using map[inplace,evalhf] can be numerically quite efficient but I would like something more general.  For example

x += x +~ v*~dt

where += in some other languages denotes an inplace addition operation and x and v are Vectors (rtable). Is there a way to do this in Maple?

If a:=[1,4,2,6,8]  create all combinations of numbers with this list below 50


I am writting a program that needs to rename variables by increasing the second index of a variable, all the variables will be named y[something,number].



If I was doing this outside maple I can see how I could use regular expressions, but I can't see how to do it in maple

i got this code, but for any n = 2N (par) i get some high errors, my M goes nuts.  anyone knwos wheres my mistake?

With(CurveFitting); Digits; 5; f := proc (x) options operator, arrow; abs(x) end proc; n := 8; h := 2/n; for i from 0 to n do x[i] := h*i-1 end do; for i from 0 to n-1 do L[i] := (product((x-x[j])/(x[i]-x[j]), j = 0 .. i-1))*(product((x-x[k])/(x[i]-x[k]), k = i+1 .. n-1)) end do; lagr := sum(f(x[p])*L[p], p = 0 .. n-1); P := expand(lagr); plot({P, f(x)}, x = -1 .. 1, y = 0 .. 2); M := maximize(abs(abs(x)-P), x = -1 .. 1); M1 := numapprox:-infnorm(abs(abs(x)-P),

x = -1 .. 1)


Thanks in advance

I didn't even know the erf function existed until doing this problem. I looked up how to use it, so I tried plugging in the explicity form into Maple, hoping it'd solve it, but it just spit back out the erf function.

I am trying to get a number answer.  A decimal. Because this is calculating a probability. How do I get Maple to give me a number here? Thanks!

so i  got this code:

But it cannot Find a value for M (wich would be the maximum distance between) it literaly stays working for severeal minutes and necer gives an answer, also i cant find a function to do this for every value for n (n-1 steps from a to b), also would mean that xy would need to get more points, any idea of how can i solve this for any n? or at least fix the problem with M, and i do the steps from a to b Manually.

heeeelp me please this is driving me nuts

thanks a lot :)


why this equation does not any answer?




eq:={-J*g[1]*(diff(w(x), x, x, x, x, x, x))+J*c[1]*(diff(w(x), x, x, x, x))+A*g[113113]*(diff(w(x), x, x, x, x))+(beta[11]*A*0)*`ΔT`*(diff(w(x), x, x))+2*b*f[1133]*(Pi/L)^2*(d[33]*lambda[3]*`ΔT`*L/mu[33]-2*f[1133]*a*Pi/L-P[3]*`ΔT`*L)*sin(Pi*x/L)*sinh(h*Pi/(2*L))/(2*cosh(h*Pi/(2*L))*(-a33+d[33]^2/mu[33])) = 0, w(0) = 0, w(L) = 0, (D(w))(0) = 0, (D(w))(L) = 0, ((D@@3)(w))(0) = 0, ((D@@3)(w))(L) = 0}

{-J*g[1]*(diff(diff(diff(diff(diff(diff(w(x), x), x), x), x), x), x))+J*c[1]*(diff(diff(diff(diff(w(x), x), x), x), x))+A*g[113113]*(diff(diff(diff(diff(w(x), x), x), x), x))+b*f[1133]*Pi^2*(d[33]*lambda[3]*`ΔT`*L/mu[33]-2*f[1133]*a*Pi/L-P[3]*`ΔT`*L)*sin(Pi*x/L)*sinh((1/2)*h*Pi/L)/(L^2*cosh((1/2)*h*Pi/L)*(-a33+d[33]^2/mu[33])) = 0, w(0) = 0, w(L) = 0, (D(w))(0) = 0, (D(w))(L) = 0, ((D@@3)(w))(0) = 0, ((D@@3)(w))(L) = 0}


dsolve(eq, w(x))





I'm trying to solve a Quantum Mechanics problem that requires me to normalize a wavefunction before I proceed. I have the book solutions to these problems (I'm just trying to practice solving using Maple) so I know what the answers are SUPPOSED to be. But I'm not getting the answers I expected when dumping it into Maple.

What I put into Maple:

What I was SUPPOSED to get:

I assume this is a radical simplication I need to make. But in highlighting the expression, right clicking, and trying the different simplification options, nothing worked.


from book example, it seems assumed that input size of data such as list size or matrix size is the same as

trained data set size, but this need to hard code infinite number of types of size

What is the method to programming neural network when input size is smaller or changing and not equal to size of trained data set?


I have a list of equations. I would like to display this list in column.
Problem : as each term of my list is an equation, i can not transform my list in a vector.
How can I do to display a list of equations in column ?

Thank you for your help.

Hi guys,

I run my code and after a point all the numerical values are followed by a dot. Why is that? Also the symbolic variables have a 1. before them.

Thanks a lot!

When I click on   I get this message 


And this has been the case for few days now. But only now I can see I can access the site if I know the internal sub link to it.  

So why is the main page down for so long?

Probably not Maple's territory, but maybe a challenge?  Can we can get maple to do this?  Done by Matlab found here..

i got 2 curves
a := abs(x);
b := (3/4)*x^2+1/4;

how can i get the max distance between them from x = -1 until x =1?


Hello! Hope everyone would be fine. I want to solve the following system of ODEs please help to find the numerical solution

N := .6; alpha := .4; beta := .1; Nt := .2; Pr := .5; Nb := .1; s := .2; lambda[1] := 1; delta := .5; gm := 1; Sc := 1:L:=1:

Eq1 := (alpha*s+1)*(diff(F(eta), eta, eta, eta))-(F(eta)+(1/2)*s*eta)*(diff(F(eta), eta, eta))+((1/2)*(diff(F(eta), eta))-s)*(diff(F(eta), eta))-2*(G(eta)^2-(1-gm)^2)-2*lambda[1]*(H(eta)+N*Y(eta))-(alpha+beta-(1/4)*delta*(diff(F(eta), eta, eta, eta)))*(diff(F(eta), eta, eta))^2-(alpha-2*beta)*(diff(F(eta), eta))*(diff(F(eta), eta, eta, eta))-(2*(alpha-beta-(1/4)*delta*(diff(F(eta), eta, eta, eta))))*(diff(G(eta), eta))^2-(2*(alpha-(1/4)*delta*(diff(F(eta), eta, eta))))*G(eta)*(diff(G(eta), eta, eta)) = 0; Eq2 := (alpha*s+1)*(diff(G(eta), eta, eta))-F(eta)*(diff(G(eta), eta))+G(eta)*(diff(F(eta), eta))+s*(1-gm-G(eta)-(1/2)*eta*(diff(G(eta), eta)))-(1/2)*alpha*s*eta*(diff(G(eta), eta, eta, eta))+((3/2)*alpha+beta)*G(eta)*(diff(F(eta), eta, eta, eta))-((1/2)*alpha+beta)*(diff(F(eta), eta))*(diff(G(eta), eta, eta))-delta*((diff(F(eta), eta, eta))^2+6*(diff(G(eta), eta))^2)*(diff(G(eta), eta, eta)) = 0; Eq3 := (diff(H(eta), eta, eta))/Pr-F(eta)*(diff(H(eta), eta))+(1/2)*H(eta)*(diff(F(eta), eta))-s*(2*H(eta)+(1/2)*eta*(diff(H(eta), eta)))+Nb*(diff(H(eta), eta))*(diff(Y(eta), eta))+Nt*(diff(H(eta), eta))^2 = 0; Eq4 := (diff(Y(eta), eta, eta))/Sc-F(eta)*(diff(Y(eta), eta))+(1/2)*Y(eta)*(diff(F(eta), eta))-s*(2*Y(eta)+(1/2)*eta*(diff(Y(eta), eta)))+Nt*(diff(H(eta), eta, eta))/Nb = 0;

IC1 := F(0) = 0, (D(F))(0) = 0, G(0) = gm, H(0) = 1, Y(0) = 1; IC2 := (D(F))(L) = 0, G(L) = 1-gm, (D(G))(L) = 0, H(L) = 0, Y(L) = 0; dsys1 := {Eq1, Eq2, Eq3, Eq4, IC1, IC2}; dsol1 := dsolve(dsys1, numeric, output = listprocedure, range = 0 .. L);

dsol1f := subs(dsol1, F(eta));

dsol1g := subs(dsol1, G(eta)); dsol1h := subs(dsol1, H(eta)); dsol1y := subs(dsol1, Y(eta));

With my best regards and sincerely.

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