I found that when changing constant of integration from _C1 to C1, Maple now fails to verify solution.

Is one supposed to only use constant with _ in it for this? I prefer to use C1 instead of _C1. Why does Maple odetest fail in this case? Is there a way around this?

Here is an example

restart;
ode:=diff(y(x),x)=x*ln(y(x)):
implicit_sol := -Ei(1, -ln(y(x)))+C1=(1/2)*x^2;
explicit_sol := solve(implicit_sol,y(x)):
odetest(y(x)=explicit_sol,ode);

Now changing C1 to _C1 and nothing else, odetest verifies the solution

implicit_sol:= subs(C1=_C1,implicit_sol);
explicit_sol := solve(implicit_sol,y(x)):
odetest(y(x)=explicit_sol,ode);

I understand the using symbol with _ is a convention in Maple for global symbols. But I want to use C1 and not _C1 as it is easier to read.

How do I convert a complex number to abs and arg presentation.

For example:

z=1+1*I would be z=sqrt(2)*exp(I*Pi/4)

or when doing a calculation how can I tell him to always present these number in that form and do not expand out.

Thanks

How I can convert my maple code to matlab?.

dsolv.mw
 

Download dsolv.mw

I want to check that all entries in a list are of some value. Say 0. (or in general, if all entries satisfy some condition).

So, If any entry is not zero, then it returns false. It returns true only if all elements meet this conditions.

What would be the right way to do this in Maple? I know I could write a loop. But I am asking if there is a build-in function in Maple. Here is an example

ode:=y(x)*diff(y(x),x)=x*(y(x)^2+2):
sol:= dsolve(ode,y(x)):
check:=map(z->odetest(z,ode1),[sol]);

                       check := [0, 0]

I want to check that all entries in check are zero. This tells me all my solution are correct.

I can't use member(check,0) since this only check if at least one entry is zero. I want to chek that all entries are zero.

In Mathematica, it has AllTrue function. Like this

check = {0, 0, 0};
AllTrue[check, # == 0 &]

     True

The "#==0&"  is the test to do. It uses this test on each element automatically. If all satisfy this test, then it returns true.

Again, I can easily write a small function in Maple to do this,

alltrue :=proc(arr,value)
    local z;
    for z in arr do
        if z<>value then
           return(false);
        fi;
    od;
    return(true);
end proc:

alltrue(check,0) return true.

But I am asking if there is a build-in such function similar to the above one in Mathematica, which accepts a more general test function to use.

why

expr:=1-3*y;
patmatch(expr, b::integer - a::integer*y,'la');

gives false but

expr:=1-3*y;
patmatch(expr, b::integer + a::integer*y,'la');

gives true?

Should one then use `+` for matching with `+` and `-`? This result was a little confusing to me. 

It is actually good that it behaves this way. Makes it easier to write the pattern (less cases to cover). But I would have expected both to return true, that is all.

I found I can start Maple itself 2 times on my windows PC. (I think my license allows max of 2, but I could be wrong).

I want to run a program which takes long time. But I want to use Maple at same time.

Which is the recommended approach:

1) Start 2 separate Maple applications. Use one to run the long program, and then I can use the second Maple for other things while the first is running)

2) Start one Maple, but set the "How should Maple handle the create of new Math engine" to "Ask me each time"

for me, choice 1 seems more safe. But thought to ask if there is something else I should consider when making which choice to pick.

Update

Found out that actually when clicking on Maple icon, I was not starting a new Maple at all. It was just starting a new worksheet using the currently running Maple ! This is confusing. With Mathematica, clicking on its icon actually starts a new complete separate Mathematica application. Not a new notebook using the currently running Mathematica.

So the question I have now is: Can one start 2 separate Maple applications on windows?  And if so, how?

Why does

MultiSeries:-series(LegendreQ(-1/2,x),x=-1))

not work?

series(LegendreQ(-1/2,x),x=-1))

seems to work, but does it give the correct result?

I actually thought there was a pole at -1.

Thx

PS: or is the cut between -1 and 1 with both logarithmic singularities?

I'm still wondering about the behaviour of MultiSeries

is there a way  for a proc() in a parent module to call an exported proc in a child module, without having to use long form of the call    child:-child_proc() and just do child_proc()?  Here is an example

A:=module()
  option package;
  export foo;
  local B; #child module

  B:=module()     
     export boo;
     boo:=proc()
        print("in B:-boo()");
     end proc;
  end module;
  
  foo:=proc()
     B:-boo();  #how can one just type  boo() here?
  end proc;
end module;

B:-foo(); now works ok. But I'd like to just use  boo() and not B:-boo() since the name of the child module is too long. 

I can't figure how to do it. I can't use with(B) in the parent, Maple complains. 

Hi 

I have a question about function as parameter in procedure

is it possible that I type 

f := x-> x+1

Test (f(x))

instead of Test(f) ? 

where Test is a simple procedure that takes in one function parameter 

Test := proc (f)
return f(1) + f (2) 

How am I going to evaluate function like this ? I tried signum evalf, eval and solve, they dont work

When a child proc calls a parent local proc using parent_module:-parent_proc(), Maple gives an error. But when the child calls the parent local proc using just parent_proc() it works. Why is that?

parent_module:=module()
 
 local child_module;
 local parent_proc;

 export parent_entry;

 child_module:= module()
    export child_entry; 
    child_entry :=proc()
     #parent_module:-parent_proc(); #this fails
     parent_proc(); #this works
    end proc;
  end module;

 #local
 parent_proc :=proc()
   print("insider parent proc");
 end proc;

 #public
 parent_entry :=proc()
   child_module:-child_entry();
 end proc;
end module;

parent_module:-parent_entry();
              "insider parent proc"

but the other way, (the commented code above) gives

parent_module:-parent_entry();
Error, (in child_entry) module does not export `parent_proc`

Bisection := proc (f, a, b, delta)

local startpoint, endpoint, midpoint; startpoint := a; endpoint := b;

do midpoint := (1/2)*startpoint+(1/2)*endpoint;

if abs(startpoint-endpoint) < delta or abs(f(midpoint)) < delta then

return midpoint

elif f(midpoint) < 0 then endpoint := midpoint

elif 0 < f(midpoint) then startpoint := midpoint

end if end do end proc

I'm trying to do a procedure for bisection method but it doesnt give me answer when  I type 

Bisection (x-> x + 0.001 , 1, -1, 0.001 )

it returns Bisection (x-> x + 0.001 , 1, -1, 0.001 )

why this is happening, Is it because the procedure is wrong ? or does not provide answer 

my main module is getting big. I want to break it to main module, and submodule. But now everything is in the same .mpl file. I'd like to put the sub module in seperate mpl file. I do not know the syntax to do this and how to do it. I looked at the programming guide chapter 8.

Currently in main_module.mpl, lets say I have this

main_module:=module()
 option package;
 local C; 
 local sub_module;
 export main_entry;

 C:=99; #see if this can be "seen" from child module

 sub_module:= module()
    export main_entry;
    main_entry :=proc()
     print("In main_module:-sub_module:-main_entry(), C=",C):
    end proc;
  end module;
 
 main_entry :=proc()
   print("in main_module:-main_entry()"):
   sub_module:-main_entry();
 end proc;
end module;

Now main_module:-main_entry(); gives

                 "in main_module:-main_entry()"
       "In main_module:-sub_module:-main_entry(), C=", 99

I'd like to move the code of the submodule to another .mpl file. So I end up with two files, like this

# main_module.mpl
main_module:=module()
 option package;
 local C; 
 local sub_module;
 export main_entry;

 C:=99; #see if this can be "seen" from child module

 main_entry :=proc()
   print("in main_module:-main_entry()"):
   sub_module:-main_entry();
 end proc;
end module;

And

#sub_module.mpl
sub_module:= module()
    export main_entry;
    main_entry :=proc()
     print("In main_module:-sub_module:-main_entry(), C=",C):
    end proc;
 end module;

But when I do this, I can't call main_module:-main_entry(); since it gives error

Error, (in main_entry) `sub_module` does not evaluate to a module
I do not want to make sub_module a separate package. I want it to remain a sub module for the main module, so it can only be seen by the main module and no one else.

So logically sub_module is a child of main_module, but physically I want to put them in separate files to make it easier to modify.

I use plain text files for everything and use Maple to load the packages and test.

How does one go about doing this? How would this be done for the above example?

I tried $include "sub_module.mpl"; but it gives error.

main_module:=module()
 option package;
 local C; 
 local sub_module;
 export main_entry;

 C:=99; #see if this can be "seen" from child module
	
 $include "sub_module.mpl";

 main_entry :=proc()
   print("in main_module:-main_entry()"):
   sub_module:-main_entry();
 end proc;
end module;

Where the file "sub_module.mpl" contains the code for the submodule I want to insert at that location. When I read "main_module.mpl" Maple gives error

read "main_module.mpl";

Error, on line 10, syntax error, unexpected string:
 $include "sub_module.mpl";

This is too advanced for me. I am still learning module and package use in Maple.

thanks

Hello all!
Can some one please help me in translating this code, for newton forward and backward interpolation, and get the same output in maple. I am not very good at matlab so that is why I am having problems converting it to maple code.

only forward or backward would be enough I am sure I will figure out the second myself.
https://www.codewithc.com/newtons-interpolation-in-matlab/

What is the best way to check if solve returned one or more solution? Currently I check if the returned sol is of type exprseq, and if so, I put the result in a list. If the sol is not of type exprseq, then I know only one solution is returned. Here is an example

foo:=proc(eq,x)
  local sol;
  sol:=solve(eq,x);
  if whattype(sol)='exprseq' then
     sol:=[sol];
  fi;
  return(sol);
end proc:

And now

Is there better way to do this?