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Ronan

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13 years, 110 days
East Grinstead, United Kingdom
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Trying to typeset Dotproduct "&." on a p...

Ronan 1022 Maple 2023
typesetting inert inertform
February 15 2024
1 1

I need to produce some diagrams for the help pages of my package. I trying to typeset the dot product "." on a plot but keep getting a % symbol. I have tried without typesetting but makes no differance.

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restart
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Sdim:=proc(A,B,C,clr::string,S:=NULL)
    description"plots spread symbol";
    uses plots,plottools;
    local aa,bb,c,d,e,f,g,h,k,p1,v1,v2,vab,vac;
    vab:=Vector(B-A);
    vac:=Vector(C-A);
    aa:=(B-A)/5;
    bb:=(C-A)/5;
    p1:=plottools:-point([A,B,C],symbol=solidcircle);
    c:= plottools:-line(A+aa,A+bb);
    d:=plottools:-line(A,B);
    e:=plottools:-line(A,C);
    f:=plots:-textplot([op(1.1*(A+(aa+bb)/2)+[1.5,0]), typeset(S)]);   #print S
    g:=plots:-textplot([op(.9*A), typeset([x[1],y[1]])]);  #[x1,y1]
    h:=plots:-textplot([op(1.1*B), typeset([x[2],y[2]])]);  #x2,y2]
    k:=plots:-textplot([op(1.05*C), typeset([x[3],y[3]])]);  #x3,y3]
    v1:=plots:-textplot([op(A+(B-A)/2+[.2,-.2]), typeset(`#mover(mi("v"),mo("⇀"))`[a])]);   # vector symbol
    v2:=plots:-textplot([op(A+(C-A)/2+[-.2,.2]), typeset(`#mover(mi("v"),mo("⇀"))`[b])]);   #vector symbol
    display(p1,c,d,e,f,g,h,k,v1,v2,axes=none,scaling=constrained,caption="Spread between two vectors");    #place title under diagram
end proc
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proc (A, B, C, clr::string, S := NULL) local aa, bb, c, d, e, f, g, h, k, p1, v1, v2, vab, vac; description "plots spread symbol"; vab := Vector(B-A); vac := Vector(C-A); aa := (1/5)*B-(1/5)*A; bb := (1/5)*C-(1/5)*A; p1 := plottools:-point([A, B, C], symbol = solidcircle); c := plottools:-line(A+aa, A+bb); d := plottools:-line(A, B); e := plottools:-line(A, C); f := plots:-textplot([op(1.1*(A+(1/2)*aa+(1/2)*bb)+[1.5, 0]), typeset(S)]); g := plots:-textplot([op(.9*A), typeset([x[1], y[1]])]); h := plots:-textplot([op(1.1*B), typeset([x[2], y[2]])]); k := plots:-textplot([op(1.05*C), typeset([x[3], y[3]])]); v1 := plots:-textplot([op((1/2)*A+(1/2)*B+[.2, -.2]), typeset(`#mover(mi("v"),mo("⇀"))`[a])]); v2 := plots:-textplot([op((1/2)*A+(1/2)*C+[-.2, .2]), typeset(`#mover(mi("v"),mo("⇀"))`[b])]); plots:-display(p1, c, d, e, f, g, h, k, v1, v2, axes = none, scaling = constrained, caption = "Spread between two vectors") end proc

 (1)
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Spr:=S=1-(`#mover(mi("v"),mo("⇀"))`[b-a]%.`#mover(mi("v"),mo("⇀"))`[b-a])^2/(`#mover(mi("v"),mo("⇀"))`[a]%.`#mover(mi("v"),mo("⇀"))`[a])/(`#mover(mi("v"),mo("⇀"))`[b]%.`#mover(mi("v"),mo("⇀"))`[b]);

S = 1-`%.`(`#mover(mi("v"),mo("⇀"))`[b-a], `#mover(mi("v"),mo("⇀"))`[b-a])^2/(`%.`(`#mover(mi("v"),mo("⇀"))`[a], `#mover(mi("v"),mo("⇀"))`[a])*`%.`(`#mover(mi("v"),mo("⇀"))`[b], `#mover(mi("v"),mo("⇀"))`[b]))

 (2)
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Sdim([1,2],[5,1],[4,7],"blue",Spr);

 
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Download Q_2024-02-15_Help_Spread_diagram.mw

Alter default setting of conjugate=true?...

Ronan 1022 Maple 2023
linearalgebra conjugate bilinearform
February 14 2024
2 2

is there a way to set conjugate=true  to false as a default for BilinearForm?  This would be used inside a package.

restart;
with(LinearAlgebra);

v := <x, y>;
BilinearForm(v, v);
BilinearForm(v, v, conjugate = false);

 

Alternative Argument spelling in a proce...

Ronan 1022 Maple 2023
parameters procedure spelling
February 09 2024
2 7

This is something I use a fair bit. I have procedures with alternative spelling options for the colours Red Green and Blue.
Have shown a single example copied from  an overloaded procedure. It there a nicer way of handling this than what I am doing?
There is a section in help under "Procedure Parameter Declarations" on "Indexed Keyword Parameters"  but I don't see how to use it here. These procedures are used inside a package.

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restart
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GeomClr:="Blue";  # can be "Blue", "blue", "B", "b"  or;
                  #        "Green", "green", "G", "g"  or;
                  #        "Red2, "red", "R", "r";

Prntmsg:="y" ; #  or anything that is not"y"
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"Blue"

  

"y"

 (1)
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spread:=proc(p0::{satisfies(s -> type(s, [algebraic $ 2])),'Vector[row]'(2, algebraic)},
              p1::{satisfies(s -> type(s, [algebraic $ 2])),'Vector[row]'(2, algebraic)},
              clr::`string`:= GeomClr,
              prnt::`string`:=Prntmsg)
           option overload;
           uses LinearAlgebra;
           #print(clr,p0,p1);
           if clr="b" or clr="B" or clr="blue" or clr="Blue" then
              if prnt="y" then
                print("Spread 2 [x,y] Points/Vectors wrt origin Blue");
              end if;
               return 1 - BilinearForm(p0, p1, conjugate = false)^2/(BilinearForm(p0, p0, conjugate = false)*BilinearForm(p1, p1, conjugate = false));
           elif clr="g" or clr="G" or clr="green" or clr="Green" then
              if prnt="y" then
               print( "Spread 2 [x,y] Points/Vectors wrt origin Green");
              end if;
               return -1/4*(p0[1]*p1[2] - p0[2]*p1[1])^2/(p0[1]*p0[2]*p1[1]*p1[2]);
           elif clr="r" or clr="R" or clr="red" or clr="Red" then
              if prnt="y" then
               print( "Spread 2 [x,y] Points/Vectors wrt origin Red");
               end if;
               return -(p0[1]*p1[2] - p0[2]*p1[1])^2/((p0[1]^2 - p0[2]^2)*(p1[1]^2 - p1[2]^2));
          end if;
          end proc:
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sb:=spread(<3|2>,<4|-5>);

"Spread 2 [x,y] Points/Vectors wrt origin Blue"

  

529/533

 (2)
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sg:=spread(<3|2>,<4|-5>,"g");

"Spread 2 [x,y] Points/Vectors wrt origin Green"

  

529/480

 (3)
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sr:=spread(<3|2>,<4|-5>,"r");

"Spread 2 [x,y] Points/Vectors wrt origin Red"

  

529/45

 (4)
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1/sb+1/sr+1/sg

2

 (5)
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sr:=spread(<3|2>,<4|-5>,"r","n");

529/45

 (6)
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Download Q_2024-02-09_Alternative_Spelling_in_Proc.mw

Overload Procedures with default values ...

Ronan 1022 Maple 2023
procedure overload default
February 02 2024
2 9

The overloaded  procedure here test returns based on 2 lists or 3 lists entered. The two list has a mixed input type with a default value. The default value of "a" can cause a problem if an explicit value in not entered for "a" in foo1. I not sure is the mixed input type is adding to the problem.
By changing the order of the procedures the problem is avoidable here. But this just a simple example. When there are 6 or so procedures it can be very difficult to select a correct ordering.

Is there a way around this, apart from don't have default values?

I could experiment with changing the input order in each proc but that would break up some logical input sequences on me.

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restart
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foo:=overload([
                        proc(P1::list,P2::list,a::algebraic:=4,$)
                         option overload;
                         print("2 lists");
                          end proc,

                       proc(P1::list,P2::list,P3::list,$)
                         option overload;
                         print("3 lists");
                          end proc
                       ]);

proc () option overload; [proc (P1::list, P2::list, a::algebraic := 4, ` $`) option overload; print("2 lists") end proc, proc (P1::list, P2::list, P3::list, ` $`) option overload; print("3 lists") end proc] end proc

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foo([1,2],[3,4])

"2 lists"

 (2)
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foo([1,2],[3,4],[4,7])

"3 lists"

 (3)
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foo1:=overload([
                        

                       proc(P1::list,P2::list,P3::list,$)
                         option overload;
                         print("3 lists");
                          end proc,

                        proc(P1::list,P2::list,a::algebraic:=4,$)
                         option overload;
                         print("2 lists");
                          end proc
                       ]);

proc () option overload; [proc (P1::list, P2::list, P3::list, ` $`) option overload; print("3 lists") end proc, proc (P1::list, P2::list, a::algebraic := 4, ` $`) option overload; print("2 lists") end proc] end proc

 (4)
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foo1([1,2],[3,4]); #incorrect output

"3 lists"

 (5)
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foo1([1,2],[3,4],4)

"2 lists"

 (6)
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foo1([1,2],[3,4],[4,7])

"3 lists"

 (7)
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Download 2024-02-3_Q_Overload_proc_.mw

Check if '=' is or is not in an equation...

Ronan 1022
type inequality
December 28 2023
3 6

How do i check if an equation or function does not contain an '=' sign, to convert it?

if eq:= a+b=c

If it has an  '=' I can use eq1:=lhs(eq)-rhs(eq).

If eq=d+e+f there is no lhs/rhs and checking produces an error.

eq := a*x^2 + b*x = v;
                               2          
                      eq := a x  + b x = v

eq1 := lhs(eq) - rhs(eq);
                            2          
                         a x  + b x - v

eq2 := a*x^2 + b*x - v;
                               2          
                     eq1 := a x  + b x - v

lhs(eq1);
Error, invalid input: lhs received a*x^2+b*x-v, which is not valid for its 1st argument, expr
NULL;
has(eq,'=');
Error, invalid uneval
        Typesetting:-mambiguous(hasApplyFunction(eqcomma

          Typesetting:-mambiguous((equals), 

          Typesetting:-merror("invalid uneval"))))


has(eq2, rhs(eq2));
Error, invalid input: rhs received eq2, which is not valid for its 1st argument, expr
NULL;

 

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