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acer

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20 years, 95 days
Ontario, Canada

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Calendar...

acer 32727
December 16 2019
0 0

@brian bovril Since Calendar is both a submodule of Finance as well as a top-level package (in Maple 2019) then you'll have to account for that if you intend on loading both.

> 

restart;
> 

kernelopts(version);

`Maple 2019.1, X86 64 LINUX, May 21 2019, Build ID 1399874`

> 

with(Finance):
> 

DayCount("13/1/2019","1/1/2019");

-12

> 

with(:-Calendar):
> 

DateDifference(Date(2019,1,13),Date(2019,1,1),units=day);

-12*Units:-Unit(d)

> 

convert(%,unit_free);

-12

> 

 

Download datediff.mw

The with command brings some quick and easy convenience for off-the-cuff coding. But it's not the best tool for programming.

sure...

acer 32727
December 15 2019
0 0

@Christopher2222 Sure, the (now deprecated) font tag is limited. But that's not specific to this use of it in Maple. I figured that you'd just research whatever HTML aspects you'd want to try.

Here is another variant on using the font-size style property.

SetProperty("Button0", ':-caption',
            "<html><p style=\"font-size:20px\">foo</p></html>",
            ':-refresh');

sorry...

acer 32727
December 14 2019
0 0

@Christian Wolinski I'm sorry, but I don't understand what you're asking. I'm not sure what you mean here by "the answer"?

This behavior of solve is not very robust, especially for more than one varaible. It's often more convenient to get it to generate a solution containing relations (inequalities) and then convert to RealRange manually if possible.

And, sure, I've seen examples where a second call to solve does indeed help (eg, by cleaning up and merging conditions).

Previously in this thread I was addressing this particular Question's original example, and I made no claim about more general applicability.

> 

restart;
> 

foo := solve({y < -1, y < x, 0 < (2*x)/(x^2 - 1), x < 1});

{-1 < x, x < 0, y < -1}

 

Of course we can check for the absence of mixed terms.

 

> 

convert(And(remove(has,foo,x)[]),RealRange);

y::(RealRange(-infinity, Open(-1)))

> 

convert(And(remove(has,foo,y)[]),RealRange);

x::(RealRange(Open(-1), Open(0)))

 

And (for the benefit of other readers) these can all be picked apart using op.

 

> 

[op(%)];

[x, RealRange(Open(-1), Open(0))]

> 

[op(%[2])];

[Open(-1), Open(0)]

> 

op(map(op,%));

-1, 0

> 

 

Download solve_rr_2.mw

or just once, as I'd shown...

acer 32727
December 14 2019
0 0

@Christian Wolinski Or call solve just once, as I'd shown an hour ago.

solve(And(-1 < x, 0 < (2*x)/(x^2 - 1), x < 1), x);

image...

acer 32727
December 14 2019
0 0

Where did the image go?

If the OP removed the image then that would be incredbly rude, given that an answer was supplied.

pardon?...

acer 32727
December 12 2019
0 0

@Christopher2222 What do you mean?

Do you mean that you want the clock to run k times as fast, from the moment the stopwatch is started?

AdjustDateField...

acer 32727
December 12 2019
0 0

@Christopher2222 Where it utilizes Today you can instead modify that using AdjustDateField.

Tod := Calendar:-Today():
New := Calendar:-AdjustDateField( Tod, "minute", 10 ):

Calendar:-Format(Tod, "hh:mm:ss a");
Calendar:-Format(New, "hh:mm:ss a");
                         "01:46:55 PM"
                         "01:56:55 PM"

clock_adj.mw

deleted content...

acer 32727
December 10 2019
0 0

The original question was defaced. It went something like this:

"Does anyone knows how to calculate determinant of a matrix with a proc or function , i mean i don't have to use "det" in maple i need a whole..."

And the original title was, "Help me with determinant calculation of a matrix".

problem class?...

acer 32727
December 10 2019
0 0

What is the class of optimization problems in which are you interested?

for fun...

acer 32727
December 06 2019
0 0

@mmcdara 
Just as a fun alternative,

> 

restart;
> 

f := (x__2+y^3)/(1+cos(y)):
> 

H:=proc(e)
     uses T=Typesetting;
     nprintf(`#%a;`,
             subsindets(convert(T:-Typeset(T:-EV(e)),`global`),
                        identical('fontstyle')=anything,u->NULL));
   end proc:
> 

 

> 

H(f);

`#mfrac(mrow(msup(mi("y"),mn("3")),mo("&plus;"),mi("x__2")),mrow(mn("1"),mo("&plus;"),mrow(mi("cos"),mo("&ApplyFunction;"),mfenced(mi("y")))));`

> 

lprint(%);

`#mfrac(mrow(msup(mi("y"),mn("3")),mo("&plus;"),mi("x__2")),mrow(mn("1"),mo("&p\

lus;"),mrow(mi("cos"),mo("&ApplyFunction;"),mfenced(mi("y")))));`

> 

 

Download for_fun.mw

Of course your mileage may vary, depending on expression.

I recall that (7.5 years ago) I wrote this.

I'm pretty sure that I've duplicated a similar thing (that also adjusts colors of fencing, etc) in several responses over the years.

It's all inter-related: MathML, Maple's Typesetting, etc.

However none of this helps directly with your original question (unless you are willing to accept a space denoting multiplication of H__2 or H[2] and O__2 or O[2], or to remove it in such mechanisms).

Even Robert's suggestion to manually form the concatenated name of a pair of symbols -- both having subscripts -- as an atomic identifier is not entirely straightforward. Backing up over a space between subscripted terms may be one step. Obtaining a result with upright Roman symbols is yet another step. And all as a one-off.

nprintf...

acer 32727
December 06 2019
0 0

One of the strengths of a programming language is that such constructs can be built programmtically.

> 

restart;
> 

 

> 

mk:=module()
  local f, ModuleApply;
  ModuleApply:=proc(L::list([symbol,posint]))
    local u;
    cat(`#mrow(`,
      f(L[1]),
      seq([`,`,f(L[u])][], u=2..nops(L)), `)`);
  end proc:
  f:=proc(LL::[symbol,posint])
    if LL[2]=1 then
      nprintf("mo(\"%a\",mathcolor = \"blue\")",LL[1]);
    else
      nprintf("msub(mo(\"%a\"),mn(\"%a\"),mathcolor = \"blue\")",
                  LL[1],LL[2]);
    end if;
  end proc:
end module:
> 

mk([[H,2],[O,1]]);

`#mrow(msub(mo("H"),mn("2"),mathcolor = "blue"),mo("O",mathcolor = "blue"))`

> 

mk([[H,2]]);

`#mrow(msub(mo("H"),mn("2"),mathcolor = "blue"))`

> 

mk([[C,8],[H,10],[N,4],[O,1]]);

`#mrow(msub(mo("C"),mn("8"),mathcolor = "blue"),msub(mo("H"),mn("10"),mathcolor = "blue"),msub(mo("N"),mn("4"),mathcolor = "blue"),mo("O",mathcolor = "blue"))`

> 

salt := mk([[Na,1],[Cl,1]]);

`#mrow(mo("Na",mathcolor = "blue"),mo("Cl",mathcolor = "blue"))`

> 

eq := salt = true;

`#mrow(mo("Na",mathcolor = "blue"),mo("Cl",mathcolor = "blue"))` = true

 

I can cut and paste from that 2D Output.

> 

eval(`#mrow(mo("Na",mathcolor = "blue"),mo("Cl",mathcolor = "blue"))`, eq)

true

> 

 

Download typemk_more.mw

space, NULL...

acer 32727
December 06 2019
0 0

@mmcdara If you lprint your example you should be able to detect that your problematic example has some hidden character or space in it.

split...

acer 32727
December 04 2019
0 0

@Axel Vogt It may be that inttrans:-fourier is splitting it, and then running into failure:

int(erf(x)*exp(-I*x*k),x = -infinity .. infinity):
lprint(%);
  -2*I*exp(-1/4*k^2)/k

int(erf(x)*cos(-I*x*k),x = -infinity .. infinity):
                     0

I*int(-erf(x)*sin(-I*x*k),x = -infinity .. infinity):
lprint(%);
  I*int(I*erf(x)*sinh(x*k),x = -infinity .. infinity)

The integrals involving erf(x)*cos(-I*x*k) and erf(x)*exp(-I*x*k) are handled successfully by method=meijergspecial.

interesting...

acer 32727
December 04 2019

This is an engaging read.

Readers who like this might also be interested in these old posts by John May: 1, 2, 3, 4, 5, 6.

not sure...

acer 32727
December 04 2019
0 0

@Magma I do not have access at this momemnt to a machine with enough RAM to complete your large example.

However, I have noticed something troubling about the performance on your smaller example (which I included in my first Comment) as shown by CodeTools:-Usage under 10 repeats.

Maple 2015.2 (or earlier, approx.)
Your BP:
memory used=41.43MiB, cpu time=229.70ms, real time=232.80ms, gc time=12.40ms
Carl's modified BP:
memory used=12.47MiB, cpu time=97.80ms, real time=97.80ms, gc time=4.41ms

Maple 2016.0 (or later, approx.)
Your BP:
memory used=193.62MiB, cpu time=1.03s, real time=990.50ms, gc time=96.95ms
Carl's modified BP:
memory used=152.51MiB, cpu time=783.60ms, real time=757.30ms, gc time=76.69ms

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