acer

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These are replies submitted by acer

@Markiyan Hirnyk See here for the source.

@serena88 The seq command takes an optional third argument, for the increment, which can be negative.

> j[[seq(i,i=13..4,-1)],1];

                    j[[13, 12, 11, 10, 9, 8, 7, 6, 5, 4], 1]

@serena88 The seq command takes an optional third argument, for the increment, which can be negative.

> j[[seq(i,i=13..4,-1)],1];

                    j[[13, 12, 11, 10, 9, 8, 7, 6, 5, 4], 1]

@Brettski If you lprint that P[0] atomic-identifier name then you'll likely see something like `#msub(mi("P"),mn("0"))`.

And that is a name (because it is wrapped in single-left name quotes). But the Maple Standard GUI knows to display it as a subscripted name.

@Brettski If you lprint that P[0] atomic-identifier name then you'll likely see something like `#msub(mi("P"),mn("0"))`.

And that is a name (because it is wrapped in single-left name quotes). But the Maple Standard GUI knows to display it as a subscripted name.

@Christopher2222 The eventual slowdown in the Standard GUI that you described when animating the globe also occurs in later Maple versions. I believe that it is due (effectively) to some kind of memory leak in the GUI that occurs when displaying many 3D plots/frames, which you might observe using the MS-Windows Task Manager or Unix/Linus `top` utility.

I encourage you (too) to submit an SCR on it. The more such problems are reported the better the chance it might get fixed.

Consider x^3-4*x+2=0 for which the solve command returns three explicit expressions containing I. Hence, some simplification may be necessary before testing for the presence of I.

restart:

p := x^3-4*x+2:
#plot(p, x=-3..3);

S := [solve( p=0, x )]:

remove( has, S, I );

                               []

remove(has, map(simplify,S,constant), I):
evalf(%);

           [1.675130870, -2.214319743, 0.5391888726]

And simplify(...,constant) may not suffice, in general. And `is` will depend upon Digits (akin to fnormal after evalf), so can also be caught out. Applying evalc@Im can turn this into zero-testing.

acer

Consider x^3-4*x+2=0 for which the solve command returns three explicit expressions containing I. Hence, some simplification may be necessary before testing for the presence of I.

restart:

p := x^3-4*x+2:
#plot(p, x=-3..3);

S := [solve( p=0, x )]:

remove( has, S, I );

                               []

remove(has, map(simplify,S,constant), I):
evalf(%);

           [1.675130870, -2.214319743, 0.5391888726]

And simplify(...,constant) may not suffice, in general. And `is` will depend upon Digits (akin to fnormal after evalf), so can also be caught out. Applying evalc@Im can turn this into zero-testing.

acer

@Markiyan Hirnyk I was just querying what you wanted. It's not hard to get it as a sum (of a product of two numbers of combinations, ie. combinat[numbcomb] calls).

N:=(s,k)->add(combinat[numbcomb](s, i)*combinat[numbcomb](i, k-i),i=0..s);

But you want a closed form for that as a symbolic sum? Can it be in terms of calls to GAMMA and hypergeom (...I'm guessing not)?

Is it just this, for n=0,1,2,3,4,...?

 PolynomialTools:-CoefficientList(expand( (1+x+x^2)^n ),x)

So, do you want something in terms of factorials?

acer

@J4James Since eq2 and bc are both sets, pass the DE system to the dsolve command as the argument,

eq2 union bc

rather than as,

{eq2 union bc}

@J4James Since eq2 and bc are both sets, pass the DE system to the dsolve command as the argument,

eq2 union bc

rather than as,

{eq2 union bc}

@Mac Dude Try setting up your links to the saved help-page using Command,package in the hyperlink. So, its hover-over balloon would say, "Help:Command,package".

(It seemed to work ok for me in Maple 15.01, using a link with either Package,command or Package/command. I saved the help page as topic Package/command. Perhaps if you posted the precise `makehelp` incantation that you used to save the page?)

@Mac Dude Try setting up your links to the saved help-page using Command,package in the hyperlink. So, its hover-over balloon would say, "Help:Command,package".

(It seemed to work ok for me in Maple 15.01, using a link with either Package,command or Package/command. I saved the help page as topic Package/command. Perhaps if you posted the precise `makehelp` incantation that you used to save the page?)

Which applications (from the Application Center) are these, that you looked at and which run in MapleV but not in modern Maple?

Did you write that they run in the Classic GUI, but not in the Standard GUI?

acer

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