From help, it says

coulditbe routine returns true if there is a possible value of x1 that satisfies prop1

my question is, how to find out this condition/possible values that Maple found?  This infomration is very useful, but now I do not see how to obtain it. All what coulditbe retuirn is true or false.

Context of why I am asking:  Sometimes odetest do not verify its own solutions. And coulditbe can help in finding under what conditions the solution can satisfy the ode. Here is an example

restart;
ode:=diff(y(x),x) = abs(y(x))+1;
solExplicit:=dsolve(ode);
offset := odetest~([solExplicit],ode)

gives

[exp(-x)/_C1 - abs((-exp(-x) + _C1)/_C1) - 1, exp(x)*_C1 - abs(exp(x)*_C1 - 1) - 1]

Both solution fail odetest. 

coulditbe~(offset,0)

gives true

So there are assumptions/conditions which makes the solution satisfy the ODE. In this case, by inspection one can see what these conditions are. They are, for one solution:

(-exp(-x) + _C1)/_C1  >0

and for the other, the condition is

exp(x)*_C1 - 1 >0

Under these assumptions, odetest would have given 0 for each odetest.

And it is this information I wanted to obtain automatically from coulditbe.

In Mathematica, Reduce is used for this. Reduce gives conditions under which something is satisfied. For example, 

Reduce[ C[1] Exp[x] - Abs[C[1] Exp[x] - 1] - 1 == 0, {x, C[1]}, Reals]

Gives

C[1] >= Exp[-x]

While the above in  Maple

coulditbe( C[1]*exp(x)- abs( C[1]*exp(x)-1)-1 = 0)

gives true  only, but without the important information, true under what conditions.

Is there a different command in Maple which could give this information?

Hi there.

I need to calculate multiplcations of huge polynoms with reducing in GF(2^m) with m>1000.

For example, modpol(a*a,f_t,t,2^N) with N=4007, degree(a)=8008 and degree(f_t)=8009.

Standard modpol calculates this in 4-5 sec on my computer.

Maybe there is an easy way to speed up this calculation?

Thank you.

ex.mw

nn.txt

Suppose I have

with(GraphTheory):
vertices:=["M","P","C"]:
edge_weights:={[{"M","P"},3],[{"M","C"},1]}:

G1:=Graph(vertices,edge_weights)

EigenvectorCentrality(G1)
                                                  

Is it right to say the EigenvalueCentrality values correspond to the names in the vertices correspondingly?  ie M corresponds to 0.4415.. P corresponds to  0.4188.. and C corresponds to 0.1396... ?

This was generated when running some code on Maple 2020.1.

Just wondering if this might indicate some problem internally, or is this something that can happen.

restart;
ZZ:=Int(-(a*_a^2+(_a^4*a^2-4*_a*b*y(x))^(1/2))/(a*_a^3+_a*(_a^4*a^2-4*_a*b*y(x))^(1/2)+6*y(x)),_a = _b .. x)+Intat(-2/(a*x^3+x*(a^2*x^4-4*_f*b*x)^(1/2)+6*_f)-Int(2/(_a^4*a^2-4*_a*_f*b)^(1/2)*b*_a/(a*_a^3+_a*(_a^4*a^2-4*_a*_f*b)^(1/2)+6*_f)+(a*_a^2+(_a^4*a^2-4*_a*_f*b)^(1/2))/(a*_a^3+_a*(_a^4*a^2-4*_a*_f*b)^(1/2)+6*_f)^2*(-2*_a^2/(_a^4*a^2-4*_a*_f*b)^(1/2)*b+6),_a = _b .. x),_f = y(x))+_C1 = 0;

timelimit(30,value(ZZ))

Error, (in discont/zero) too many levels of recursion

The problem is that I am not able to trap the error. This does not work

try
ZZ:=Int(-(a*_a^2+(_a^4*a^2-4*_a*b*y(x))^(1/2))/(a*_a^3+_a*(_a^4*a^2-4*_a*b*y(x))^(1/2)+6*y(x)),_a = _b .. x)+Intat(-2/(a*x^3+x*(a^2*x^4-4*_f*b*x)^(1/2)+6*_f)-Int(2/(_a^4*a^2-4*_a*_f*b)^(1/2)*b*_a/(a*_a^3+_a*(_a^4*a^2-4*_a*_f*b)^(1/2)+6*_f)+(a*_a^2+(_a^4*a^2-4*_a*_f*b)^(1/2))/(a*_a^3+_a*(_a^4*a^2-4*_a*_f*b)^(1/2)+6*_f)^2*(-2*_a^2/(_a^4*a^2-4*_a*_f*b)^(1/2)*b+6),_a = _b .. x),_f = y(x))+_C1 = 0;
timelimit(30,value(ZZ));
catch:
  print("ignore");
end try;

Error, (in discont/zero) too many levels of recursion

Why can't one catch this error inside try/catch? It means the whole program can not  continue.

Maple 2020.1

Update Jan 9, 2025

This bug is still in Maple 2024.2. Will check again in 5 years. May be someone in Maplesoft will fix it by then.

Download not_fixed_jan_9_2025.mw

Hi!

I try to figure out how to add »kr« as a currency symbol, and as currency in the Numeric Formatting list.

Can it be done?

Kind regards

This works

restart;
patmatch(3*g(x),A::nonunit(algebraic)*B::function,'la');
la

[A = 3, B = g(x)]

But this fails

restart;
patmatch(3*g(x),conditional(A::nonunit(algebraic)*B::function, true ),'la');

Error, (in PatternMatching:-AlgStruct:-Match) improper op or subscript selector
 

I am not able to see why. In the above I used true for the condition, just to keep things simple. Any boolean valued expression will work.  

changing the above to

restart;
patmatch(3*g(x),conditional(A::anything*B::function, true ),'la');

it works. No error. [A = 3, B = g(x)]

What did I do wrong in the above syntax which generated the error?

Maple 2020.1

Could anyone show me the exact command lines or exact steps to install the FGb package, specifically FGb-1.68.x86_64_linux.tar.gz here, to Maple 2020 in Linux Ubuntu? Many thanks.

FYI, here is one of the error messages I got: 

"mv <14539>/*.so <~/maple2020>
bash: syntax error near unexpected token `14539'"

Download ellipticIntegralTest.mw

Hi everyone, 

I am trying to use elliptic integral from Maple, however, it did not generate any result. Can you help me with that?

let me just explains the big picture first, then give small example.

When using standard modules, I had one module, and number of smaller modules, all private to the main module. This worked well.

Each sub module, can only be accessed from the top module, which is seen by user. The sub modules can't be called by user directly.

Now I changed the main module to become an object (since I want to make more instances of it).

I want to still use the code in those submodules I had, but want to keep them private to the object class, so they can be seen only from inside the object class methods. So they are part of the object class now. But remain as modules. I do not want to copy all those methods in these submodules and put them in the object class directly.

But I can't get the syntax right to do this. I do not want to modify the code inside the sub-modules, but only how to integrate them into the object.

Notice that I can call those external modules fine from the object, but I simply want to make them private to the object class, so they can't be called from outside. 

The question is how to do this? 

Here is a very small example. (in practice, I have these submodules in .mpl files, but here I put them all in the example).

restart;	
module car_class()
      option object;
      local name::string :="UNKNOWN";

      export set_name::static:=proc(o::car_class,_name::string)
        o:-name := _name;
        o:-big_car:-set_name(o,_name);#this call does not work
      end proc;

      #this is module, that I want to be private to this class only
      #eventually, I'd like this module be in separate mpl file also.
      local big_car::static :=module()  #module does not take arguments!

            #this below should be private only to the this module
            #and not seen by the enclosing object.
            local big_car_name::string:="UNKNOWN";  

            #this export to allow parent object to call it
            export set_name::static:=proc(o::car_class,_name::string)
                   o:-big_car:-big_car_name:=_name;
            end proc;

      end module;

end module:

o:=Object(car_class);
o:-set_name(o,"GM");

Error, (in set_name) module `car_class` does not export `big_car`

I found after playing more with it, that this works

I just replaced o:-big_car:-big_car_name:=_name;  with big_car:-big_car_name:=_name; had to remove ::static from definition of proc inside the private module.

restart;	
module car_class()
      option object;
      local name::string :="UNKNOWN";

      export set_name::static:=proc(o::car_class,_name::string)
        o:-name := _name;
        o:-big_car:-set_name(o,_name);
      end proc;

      local big_car::static  :=module() 
          local big_car_name::string:="UNKNOWN";  

          export set_name:=proc(o::car_class,_name::string)
              big_car_name:=_name;
          end proc;

     end module;
end module:

Now it works. However, maple help says "In Maple, method names should be declared as static. "

If one refers to a name in Maple, I thought it will look at the global context to find it. So when one does latex(....) then this is assumed to be the system latex command. No need to do :-latex()

But if there is local variable in Object class called latex, why then is object:-latex gets confused with global Maple command latex()?  Here is an example

module ode_class()
      option object;
      local latex::strring :="";

      export init::static:=proc(o::ode_class)
        o:-latex:= latex(1/2,output=string);
      end proc;
end module:

my_ode:=Object(ode_class): 

Error, static procedure `ode_class:-init` refers to non-static local or export `ode_class:-latex::strring` in surrounding scope
 

ofcourse easy to fix, I just replace the RHS latex(1/2,output=string);  with :-latex(1/2,output=string); 

But my question why is object:-latex := latex(...)  makes Maple think the latex in the RHS is the variable name in the class, when it does not have the  object:- prefix?  Is this expected  behaviour in Maple? 

But now I am starting to worry that each maple command/function/name used inside the Object needs  :- added to it, just in case of a current or future name conflict with local object variables names.

in my object, I have few private variables. To make sure the object is correctly initialized between each use, I'd like to initialize these private variables each time at the start of the call each time the object is called to process something.

Some of these variables represent equations, or symbols or functions. Some of these are set by the user of the object, but some are not. And I do not want to leave those that are not set, using old values from last call.

The problem  I can't use {} nor NULL to initialized these private variables, since I am telling Maple they are of type `=` or `symbol` or `function`.

To give a small example, I use a proc here to illustrate, since it the same idea, but less code.

restart;
kernelopts('assertlevel'=2):
foo:=proc(input_ode::`=`)
   local ode::`=`:={};  #i'd like to give this some initial value. But what?
   ode:=input_ode;
end proc;

now foo(diff(y(x),x)=5) gives

Error, (in foo) assertion failed in assignment, expected `=`, got {}
Same type of error happens if I use NULL.

Is there a special value or tag one can use to initialize/reset any variable, regardless of its type? I thought at first that NULL will work, but it is not.

The idea is that I'd like all my object private variable to always have known state when the same object is called each time. ie. to clean it up before the next time is made.

The above is just an example. Ofcourse I could just do this

restart;
kernelopts('assertlevel'=2):
foo:=proc(input_ode::`=`)
   local ode::`=`; #leave it un-initialized since it will be overwritten next
   ode:=input_ode;
end proc;

And now no error. 

I read  help document of :

But if I want to use Composition function , is it not useful? why? how to do?

we know that:

Error, (in Compiler:-Setup) unable to write to initialization file, C:\Program Files\Maple 2020\bin.X86_64_WINDOWS/launch.ini, possibly due to insufficient permissions
NULL;

when choose bat file

but i see sufficient permission

any w should i s

choose a particular compiler or even visual studio i have in my system

where can i find if anything else