Hi, I'm on Maple 2020 on Mac, and running this:

" />

In fact, that isn't the Chromatic number of that graph. Is not possible to color that graph with 2 colors becuase C7 (Cycle with 7 vertex) is a subgraph which is imposible to color with 2 colors. Am I doing something wrong? Can you replicate this? Is this a bug or is me?

Thanks

Dear all

I want if possible to solve the inequation   f(x,y)>0 using maple

positive_function.mw

Thanks for any help

Maple formerly accepted

rule1 := forall(string(y), TD(y) = D(y)):

but now that statement prodices an error message:

Error, (in forall) expecting bound variable(s) to be a name or list of unique names

The entire value of this forall structure is that it should apply to objects of specific types, but it is not obvious how to express those types; the Help page for 'forall' is essentially useless in relation to this question. 

Hi, I am a beginner of maple and I met a problem recently.

I extracted some equations from a .txt file like below:

> read “D:/blablabla/filename”

                       EQ_1,EQ_2,...

Then I want to collect all these equations to make a list EQlist=[EQ_1,EQ_2,...] but the following code doesn't work:

> EQlist:=read “D:/blablabla/filename”

Error, invalid assignment

Could anyone tell me how to construct such EQlist?

Thank you in advance.  P.S. I can't just copy and paste because these commands are supposed to be in a loop.

Dear maple users,

Greetings.

How to plot this function equation "An" for x=0.0001..1,0.02 with 0..1 range.

Wating for replay.

restart;
A2 := 1.107444364; A4 := 1.124502164; ad := .5; ed := 0.1e-1; pd := 21; ld := .3;
f := unapply(3*x^2-2*x^3-1.238616691*x^2*(x-1)^2-.7382714588*x^2*(x-1)^3+.1921034396*x^2*(x-1)^4+.5253305667*x^2*(x-1)^5+.7364291997*x^2*(x-1)^6+1.032724351*x^2*(x-1)^7+.8058204155*x^2*(x-1)^8+.3290860035*x^2*(x-1)^9, x);
t := unapply(.339997432+1.547096375*x^2-2.488736512*x^3+8.154594212*x^4-15.63643668*x^5+15.85832377*x^6-8.734300202*x^7+1.959461605*x^8, x);
b1 := f(x);
b2 := diff(f(x), x);
b3 := diff(f(x), x, x);
b4 := t(x);
b5 := diff(t(x), x);
An := A4*(1+(4/3)*ad)*(b5^2+b4^2/ld^2)+4*ed*pd*(b2^2/x^2+b1^2/x^4-b1*b2/x^3)/ld;
As := seq(An, x = 0.1e-2 .. 1, 0.5e-1);
L := [seq([x, As], x = 0.1e-2 .. 1, 0.5e-1)];

with(plots);
plots:-display(plot(L, style = point), plot(As, x = 0.1e-2 .. 1), color = blue, linestyle = solid, labels = ["η", "f'"], thickness = 1, labeldirections = [horizontal, vertical], labelfont = ['TIMES', 'BOLDOBLIQUE', 16], size = [450, 450], axes = box);
mp.mw
 

Download mp.mw

Is this a bug?

eq:=5*x+y-10=0:
eq2:=y=solve(eq,y):

f:=(x,y)->eq2
                              
f(3,1)
                   

I think the way I applied it above is a bit unorthodox to Maple but maybe it is a bug.  Normally I think we use unapply in this situation. 

f:=unapply(eq2,x,y)
                             
f(3,1)
                     

Okay better, but I think that first way should work no?

Hi guys,

I want to solve the matrix equation. suppose we have a matrix A 4*4 which only first array of it (1,1) is equal to n and another matrix such as S which is again 4*4 and generally, we don't know its arrays and we want A and S satisfy the following equation:

S*A*inverse(S)=A

how we can find out arrays of S?

A=Matrix([[1,0,0,0],[0,0,0,0],[0,0,0,0],[0,0,0,0]])

S=Matrix([[a,b,c,d],[e,f,g,h],[I,j,k,l],[m,n,o,p]])

thanks

I have a .mla file, filename.mla, in a folder and typed with(filename), but Maple says "Error, invalid input: with expects its 1st argument, pname, to be of type {`module`, package}, but received convex". So how to use a  .mla file in Maple exactly?

Thanks a lot.

Years ago i used maple as in a worksheet

Nowadys there are two ways to use Maple: in document mode and worksheet mode ?

Very confusing this and it seems that the old worksheet mode has nothing to do with the document mode
 

Now in Maple i don't now how to use the worksheet mode anymore.
Can this worksheet mode used togehter with the document mode?

This is real troublesome exercise  to use Maple, why should i use the document mode and offers it the same functionality as in the worksheet mode ?

I am trying to isolate theta/V in this equation, but Maple will only allow me to solve for either theta or V. Is there a way to make Maple solve for the expression instead of the variable?

I have attached the Maple document below. It contains some other stuff but it is mostly this equation I am interested in. It can be found near the bottom. I hope someone can help.

Best regards

Opdelt_TF_Maple.mw

Why does Maple product history page   stop at Maple 6, year 2000?

Maple starterd in 1984. There are more versions before version 6. I think this official Maple page should list every release made in Maple and do not understand why it stop at version 6 only.

Wikipedia has more complete and detailed history of Maple products, starting with version 1 in 1982, with minor versions also shown than Maple own official web page gives.

btw, Wilipedia says version 6 was released in December 6, 1999. But Maple official page says version 6 was released in 2000.  

Any help why this code fail

restart;
PDE := diff(u(x,y), y$2 ) + diff(u(x,y), x$2) = 0;
BC:= u(x,0)=0, u(x,100)=100, u(0,y)=0, u(10,y)=0;
sol:=pdsolve([PDE,BC],numeric);

gives

Error, (in pdsolve/numeric/process_PDEs) PDEs can only contain dependent variables with direct dependence on the independent variables of the problem, got {u(0, y), u(10, y), u(x, 0), u(x, 100)}
 

But sol:=pdsolve([PDE,BC])  works OK and gives analytical solution.

What error Am I doing in the above code in this case?

Maple 2020 with Physics 642

Is there any possibility to define which units are used in components, like MathContainers?

I would like to have kN/m, I get mm2*kg/m3*m/s2...

I'd like to find chromatic number of some graphs. But I find a strange thing of function ChromaticNumber. 

It is Ok!

But when I use following codes, an error will be issued.

I try to take a partial derivative of compound expressions. Usage of diff, Diff, substitution variables instead of time-variant variables (subs) couldn't help me.

Download DiffExpr.mw

Should I use implicitdiff? If yes, how does it work?

Also, I don't understand, why the derivative of theta_l is displayed so strange, as if the derivative is taken from the index l?

P.S. This question is a continuation of my last topic: https://www.mapleprimes.com/questions/229551-Operations-On-Several-Defined-Functions