Christian Wolinski

MaplePrimes Activity


These are replies submitted by Christian Wolinski

@Joe Riel I think it should be:
 

SplitString := proc(s,len)
local i;
    seq(s[i..i+len-1], i=1..length(s), len);
end proc:

Same error with 1150900 and 1150900+1. As a matter of fact 1150000..1150900 is ok. And so is 1151000..1152000. And 1150952..1151000 but not 1150951. Presumably nothing in the range 1150901..1150951 works.

So checking on 1073152, it works. 1073128 works too, but 
1073127 does not. So presumably nothing in the range 1073101..1073127 works.

@WA573 

select(proc(Sol, Sub) map(evalb, subs(Sub, Sol))={true}; evalb(%); end, Sols, {c = c0, mu = 1/sqrt(2*c0^2-2), a[-1] = a[-1], a[0] = 0, a[1] = a[1], b[-1] = a[-1], b[0] = 0, b[1] = -a[1]});

select(proc(Sol, Sub) evalb(map(evalb, subs(Sol, Sub))={true}); end, Sols, {c = c0, mu = 1/sqrt(2*c0^2-2), a[-1] = a[-1], a[0] = 0, a[1] = a[1], b[-1] = a[-1], b[0] = 0, b[1] = -a[1]});

 

@WA573 If you dontt like map allvalues you can do this:
Sols := [solve]({c=c0, identity(Eq3,z)},vars, explicit=true); NSols := nops(Sols);

"Extracting" the values can be done in this way:
map(subs, Sols, [c, mu, a[-1], a[0], a[1], b[-1], b[0], b[1]]);

or with one of these:
map(proc(S,V) [subs(S, V), map(lhs, select(evalb, S))] end, Sols, [c, mu, a[-1], a[0], a[1], b[-1], b[0], b[1]]);
map(proc(S,V,k) local i; [subs(S, V), map(lhs, ([op]@select)(evalb, S))]; subs([seq(%[2][i]=k[i], i=1..nops(%[2]))], %)  end, Sols, [c, mu, a[-1], a[0], a[1], b[-1], b[0], b[1]], k);

 

@Ronan Maybe it is a version issue.

@Ronan Instead of end, try end proc. Also did you get the `` in the ``(lcoeff(E))*normal(E/lcoeff(E)) ? Maybe you should change your input options in Options/Display/Input display to Maple Notation.

Also in
if type(E, `+`) then X := [op]('E') else X := ['E'] fi; 
notice that E is not a variable, but the very expression evaluated as argument. Evaluating it further is not desired. We mean only to deconstruct it or to use it in a construction.

Could you post the result of

kk:=FFT(GenerateJaehne(n,1));

 

@Carl Love The user may be working with a list/vector.

The only difference I can see between the plots is:
using option color=[red,red] in display produces a PLOT3D structure with 2 MESH structures with a COLOUR specification,
using option color=red in 2 tubeplots produces a PLOT3D structure with 2 MESH structures with a COLOR specification.
Both tubes are red and there are no black objects.

I am using Maple 2017.3.

If you use solution of the first system in the second, none of the equations verify unless you heavily reduce Digits. You are having precision issues.

@acer You can use this:

h := proc(g) proc(a) option operator, arrow; proc(b) option operator, arrow; g(a, b); end; end; end;
g:=unapply(a/b, a, b);
f:=h(g);
f:=h(eval(g));
f:=h(unapply(a/b, a, b));


Though the body will not display the formula used to make g, just letter g or its definition, depending what you submitted.

@Carl Love Strangely thickness has to be type nonnegint with my version of Maple.

restart:
Digits:= 15:
V:= [x,y,z]:
eqs:= diff~(V(t), t)=~ [35*(y-x), -x*z-7*x+28*y, x*y-3*z](t);
sol:= dsolve({eqs[], (V(0)=~ V||~0)[]}, numeric, maxfun= -1, parameters= V||~0);
sol(parameters= ['rand(0.0..1.)()' $ 3]);
plots:-odeplot(sol, V(t), t= 0..50, numpoints= 15000, thickness= 0,transparency=0.8, axes=normal,
axis[1]=[location=origin,thickness=0], axis[2]=[location=origin,thickness=0], axis[3]=[location=origin,thickness=0],
scaling=unconstrained, orientation=[-45, 45, 0]);

 

@Carl Love Thank You. I never expected anything like overload in Maple. Considering how poor this implement is your tool is very useful. What I am trying to do is to ensure that my code is using default, builtin Maple procedures for operations like:

:=, +, -, *, /, ^
@, @@,
[], {},
if, ifelse

and anything I use commonly. I was hoping to be able to use the "use in end use" clause, but nothing like that exists in Maple.

@Preben Alsholm I believe this is the closest we can get to the sought form.

@Carl Love This wont work with:

main:= ():
main:-`+`(1, 1.1);
use main in 1+1.1 end use;


main is not a module.

3 4 5 6 7 8 9 Last Page 5 of 21