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How to overload a method in module with option obj...

Asked by: nm 11538
module overload object
October 29 2023
2  1

Maple 2023.1 will not let me overload a method for an object when using _self.  Is there a way around this?

module person()
   option object;
   local the_name::string:="*",the_age;

   export set_info::static:= overload(
   [
      proc(_self,the_name::string,$) option overload;
          _self:-the_name:=the_name;
      end proc,

      proc(_self,the_name::string,the_age::integer, $) option overload;
          _self:-the_name:=the_name;
          _self:-the_age:=the_age;
      end proc
   ]);

   export get_name::static:=proc(_self,$)
      RETURN(_self:-the_name);
   end proc;
end module;

And now when I do 

o:=Object(person);
o:-set_info("me");
o:-set_info("me",20)

Error, (in person:-set_info) `me` does not evaluate to a module
Error, invalid input: no implementation of person:-set_info 
matches the arguments in call, 'person:-set_info("me",20)'

The problem goes away by removing `_self` as first argument in signature of the overloaded method. But then I will not be able to use _self any more inside the methods.

There is no problem overloading the method when using normal module, or one that does not use _self. For example this works

restart;

module person() 
   export set_info:= overload(
   [
      proc(the_name::string,$) option overload;
          print(the_name);
      end proc,

      proc(the_name::string,the_age::integer, $) option overload;
          print(the_name);
          print(the_age);
      end proc
   ]);
end module;

person:-set_info("me");
person:-set_info("me",20)

How to make the first example above work? I need to overload a method inside an module with option object that uses _self

update

I found a workaround. But it is not good, but for now. For the overloaded method, instead of using 
           o:-set_info("me");

This works instead

         set_info(o,"me");

So the following now works

o:=Object(person);

#o:-set_info("me");   #do not use with overloaded
#o:-set_info("me",20); #do not use with overloaded

set_info(o,"me");  #now works OK with no error
set_info(o,"me",20); #now works OK with no error

o:-get_name();  #OK since this method  is not overloaded
o:-get_age();  #OK since this method  is not overloaded

I do not understand why _self can't be used with overloaded methods and if this a bug or by design. 

Maple 2023.1 on windows 10

67588

> 

interface(version);

`Standard Worksheet Interface, Maple 2023.1, Windows 10, July 7 2023 Build ID 1723669`

> 

restart;

67588

> 

module person()
   option object;
   local the_name::string:="*",the_age;

   export set_info::static:= overload(
   [
      proc(_self,the_name::string,$) option overload;
           #print("Inside first overloaded set_info");
          _self:-the_name:=the_name;
      end proc,

      proc(_self,the_name::string,the_age::integer, $) option overload;
          #print("Inside second overloaded set_info");
          _self:-the_name:=the_name;
          _self:-the_age:=the_age;
      end proc
   ]);

   export get_name::static:=proc(_self,$)
      RETURN(_self:-the_name);
   end proc;

   export get_age::static:=proc(_self,$)
      RETURN(_self:-the_age);
   end proc;
end module;

module person () local the_name::string, the_age; option object; end module

> 

o:=Object(person);
#o:-set_info("me");
#o:-set_info("me",20);

set_info(o,"me"):
set_info(o,"me",20):

o:-get_name();
o:-get_age();

module person () local the_name::string, the_age; option object; end module

"me"

20

> 

 

Download self_with_overloaded.mw

Is there a "partial sorting" command in Maple?...

Asked by: sursumCorda 1279
sort
October 28 2023
2  20

In short, I'd like to obtain n largest/smallest elements in a huge list of (probably non-numeric) data. Of cource I can sort it and then extract the desired part, yet isn't there a dedicated procedure that do a partial sort of the input data in Maple?

Edit. In a MatLab weblog, the blogger gave: 

So I believe that a dedicated one is not useless. But what is the Maple equivalent to MatLab's maxk, mink, and topkrows?

Slow manipulations in Maple Standard GUI...

Asked by: Andriy 270
performance worksheet gui
October 27 2023
1  3

Hi all

I need your advice on Maple usage after a long break. I installed Maple on my laptop and first of all tried to launch my old program. Surprisingly, the old file opened. While the core Maple functionality remained familiar, the user interface had undergone some changes.

Yet, I soon encountered challenges when attempting to perform even the simplest operations, like file browsing or text selection; the Maple Standard GUI seemed uncharacteristically sluggish.  I switched to Maple Input mode but it didn't help much. Are there ways to improve my experience with Maple? Is it caused by the outdated hardware?

My system:
Ubuntu 22.04.3 LTS
Dell Inc. Latitude 5510 (1TB SSD, 32GB RAM).

Maybe it works much better on Windows?

Thank you for any suggestions.

labels and tickmarks problem...

Asked by: jestrup 70
plotting tickmarks
October 26 2023
1  6

I have a small problem that I can't find a solution for. How do you draw a diagram like the one shown in Maple? I can't figure out how to rotate the column labels or define tickmarks as text.

Can anyone help?

Problem viewing data tables in maple cloud viewer...

Asked by: Jean-Baptiste Runge 5
maplecloud datatable
October 26 2023
1  1

Hi, 

Some of my maple documents contain data tables. 

When I want to view these documents with the maple cloud viewer, the data tables are invisible (the table is completely grayed out) and it is therefore impossible to change the values in this table. 

The table properties are such that it is enabled, visible and editable. 
Does anyone have an idea how to solve this problem? 
Thanks in advance. 

How do I fix error in Array?...

Asked by: Carolyn Davis 15
syntax sin user-error
October 24 2023
0  1

Can anyone please assist with these errors?

> 

#Clear memory.
restart;

#Initialise variables and arrays.
h:=Pi/10;
n:=10;
k:=0.1;  
m:=6;
t:=Array(0..m):
x:=Array(0..n):
u:=Array(0..n,0..m):

#Initialise the x array and the initial u(x,0) boundary.
for i from 0 to n do
    x[i]:=i*h;
    u[i,0]:=0;
end do:

#Initialise the t array and the u(x,t) side boundaries.
for j from 0 to m do
   t[j]:=j*k;
   u[0,j]:=0;
   u[n,j]:=3*sin*t[j];
end do:

#Use the 2D CTCS explicit wave method.
for i from 1 to n-1 do
   u[i,1]:=(u[i-1,0]/2*Pi^2+sin(x)/10*Pi^2+u[i+1,0]/2*Pi^2)-1;
end do:
 
for j from 1 to m-1 do
  for i from 1 to n-1 do
   u[i,j+1]:=(((u[i-1,j]+u[i+1,j]-u[i,j-1])/Pi^2)-2);
  end do;
end do:

#Display the u(x,t)values.
printf("2D CTCS Explicit Wave Method\n");
printf("----------------------------\n");
printf("x\t\t t\t\t u\n");
for i from 0 to n do
   printf("% f\t% f\t% f\n",x[i],t[m],u[i,m]);
end do;

(1/10)*Pi

  

10

  

.1

  

6

  

Error, invalid input: sin expects its 1st argument, x, to be of type algebraic, but received Array(0..10, [0,1/10*Pi,1/5*Pi,3/10*Pi,2/5*Pi,1/2*Pi,3/5*Pi,7/10*Pi,4/5*Pi,9/10*Pi,Pi])

  

2D CTCS Explicit Wave Method
----------------------------
x                 t                 u
 0.000000         0.600000         0.000000
 0.314159         0.600000        -2.015556
 0.628319         0.600000        -2.198509
 0.942478         0.600000        -2.215724
 1.256637         0.600000        -2.218015
 1.570796         0.600000        

  

Error, (in fprintf) number expected for floating point format

  
> 

NULL


Download Asst_4_Question_2c.mw

Has anybody had this strange error: Maple does not...

Asked by: C_R 3497
crash java windows10
October 24 2023
3  1

Both, Maple and MapleSim in Versions from 2021 to 2023 do not start. A logfile is saved which starts as

# A fatal error has been detected by the Java Runtime Environment:

#

#  EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x0000000000000000, pid=17256, tid=10520

#

# JRE version: OpenJDK Runtime Environment Temurin-19.0.1+10 (19.0.1+10) (build 19.0.1+10)

# Java VM: OpenJDK 64-Bit Server VM Temurin-19.0.1+10 (19.0.1+10, mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, windows-amd64)

# Problematic frame:

# C  0x0000000000000000

#

This only occurs when the notebook (on which the error occurs) is connected to the domain network. If the notebook is not connected, Maple and MapleSim can be started and will continue to run when the network is reconnected.

Has anybody seen this before or any ideas what this could be?

Edit: This all happened under Windows 10 on a notebook that has been running Maple for 3 years and only recently displayed this error.

Edit2: Connection via an USB doc which also connects to an external monitor.

Maple Editor (maple-input instead of 2d-input )...

Asked by: 2cUniverse 115
2dmath worksheet style
October 23 2023
1  9

Since I have updated from Maple 2021 to 2023 something is wrong with my stylesheets.

I rephrase my qeustion here:

I like to change the text-style of 2D-Input to courant 12, bold, color x, no italic.

Now it is courant 12, black, italic when opening a new worksheet.

I was going to format, style, 2D-input, modify and then the font has changed when opening a new woksheet but the color is going back to black and its also italic courant when pressing enter in that worksheet.

I When opening a new worksheet, i don't want ot looad an new style set by hand every time.

 

Thanks for support

 

 

solution of differential equations...

Asked by: emersondiaz 60
ode syntax dsolve
October 22 2023
2  5

Good day to all the members who read this question.
I ask for your help to find the right way to solve this two differential equations (is attached the file). Used the common code "dsolve" but is not working on this problem. Doesn't matter if the solution is numeric or algebraic.
I will thaks a lot your kind help.
Best regards to all of you

DIFFERENTIAL_EQUATION.mw

restart

with(PDEtools)

First Part

The differential equation to solve:

(Delta*LinearAlgebra:-Transpose(D[1/2])*D__0-I*`μ__e`*D__0/(lambda+I*`μ__e`*r)-2*(`μ__e`^2*r^2+lambda^2))*R(r)

Definitions

D__n = `∂__r`+I*omega(a^2+r^2)/Delta+I*a*m/Delta+2*n*(r-M)/Delta

LinearAlgebra:-Transpose(D[n]) = `∂__r`-I*omega(a^2+r^2)/Delta-I*a*m/Delta+2*n*(r-M)/Delta

a := 1; M := 1; omega := 1; m := 1; `μ__e` := 1; lambda := 1

Delta := -2*M*r+a^2+r^2

I divided the differential equation in 3 parts (A, B, C).

A := (-I*omega(a^2+r^2)-I*a*m+r-M)*(diff(R(r), r)+I*omega(a^2+r^2)*R(r)/Delta+I*a*m*R(r)/Delta)+Delta*(diff(R(r), r, r))+I*omega(a^2+r^2)*(diff(R(r), r))+I*a*m*(diff(R(r), r))

B := -I*`μ__e`*(diff(R(r), r)+I*omega(a^2+r^2)*R(r)/Delta+I*a*m*R(r)/Delta)/(lambda+I*`μ__e`*r)

C := -(2*(`μ__e`^2*r^2+lambda^2))*R(r)

DE := A+B+C

E := dsolve(DE)

R(r) = DESol({diff(diff(_Y(r), r), r)-(1-r+I/(1+I*r))*(diff(_Y(r), r))/(r^2-2*r+1)-(-(2*I)*((-1-2*I)+r)/(r^2-2*r+1)-2/((1+I*r)*(r^2-2*r+1))+2*r^2+2)*_Y(r)/(r^2-2*r+1)}, {_Y(r)})

 (1)

dsolve({DE, DE(0) = 1}, numeric, range = 0 .. 20)

Error, (in dsolve/numeric/type_check) insufficient initial/boundary value information for procedure defined problem

  

Second Part

The differential equation to solve:

[`#msub(mi("L",fontweight = "bold"),mfrac(mn("1",fontweight = "bold"),mn("2",fontweight = "bold"),linethickness = "1"))`*LinearAlgebra:-Transpose(L[1/2])+a*`μ__e`*sin(theta)*LinearAlgebra:-Transpose(L[1/2])/(lambda+a*`μ__e`*cos(theta))+2*(lambda^2+a^2*`μ__e`*cos(theta)^2)]*S(theta) = 0

Definitions:

L__n = a*omega*`sinθ`+m*`cosecθ`+n*`cotθ`+`∂__θ`

LinearAlgebra:-Transpose(L[n]) = -a*omega*`sinθ`-m*`cosecθ`+n*`cotθ`+`∂__θ`

Also I divided the differential equation in 3 parts (A, B, C).

F := (omega*a*sin(theta)+m/sin(theta)+1/(2*tan(theta)))(diff(S(theta), theta)-omega*a*sin(theta)*S(theta)-m*S(theta)/sin(theta)+S(theta)/(2*tan(theta)))+diff(S(theta), theta, theta)-omega*a*sin(theta)*(diff(S(theta), theta))-m*(diff(S(theta), theta))/sin(theta)+(diff(S(theta), theta))/(2*tan(theta))

G := a*`μ__e`*sin(theta)*(diff(S(theta), theta)-omega*a*sin(theta)*S(theta)-m*S(theta)/sin(theta)+S(theta)/(2*tan(theta)))/(lambda+a*`μ__e`*cos(theta))

H := (2*(lambda^2+a^2*`μ__e`*cos(theta)^2))*S(theta)

DF := F+G+H

dsolve(DF)

dsolve({DF, DF(0) = 1}, numeric, range = 0 .. 20)

Error, (in dsolve/numeric/type_check) insufficient initial/boundary value information for procedure defined problem

  

NULL

Download DIFFERENTIAL_EQUATION.mw

Why does this worksheet calculates for ever?...

Asked by: FDS 220
procedure
October 22 2023
0  18

Dear Power Users, I tried to make a model in Maple but after several hours of struggling I need some help. Can someone tell me what I did wrong or explain to me what is the meaning of the maplemint comment on procedure (optimalisatie)? Thank you in advance.

DiLeoCasper.mw 

How do I program Maple to display consective numbe...

Asked by: Carolyn Davis 15
seq printf
October 21 2023
0  2

For the t output I need to show 1, 1.2, 1.4....2, my attempt is highlighted in green below

Can anyone assist please?

> 

#Clear memory and load packages.
restart;
with(plots):
with(Statistics):

#Define vectors and variables.
actual:=<2,3.5136,5.8016,9.1136,13.7376,20>:
t:=<1,1.2,1.4,1.6,1.8,2>:
n:=6:
RMSE:=0:

#Perform a simple linear regression on the data.
P:=LinearFit([1,x],t,actual,x);

#Display the model errors.
printf("t    Actual P  Model P  Error\n");
for i from 1 to n do
   model:=subs(x=t[i],P):
   err:=actual[i]-model:
   RMSE:=RMSE+err^2:
   printf("%2d %7.4f% 10.4f% 9.4f\n",(i+(1/5)),actual[i],model,err);
end do:

#Display the root mean square error.
RMSE:=sqrt(RMSE/n);

#Plot the points and the model.
p1:=plot(t,actual,style=point,view=[0..7,8..26]):
p2:=plot(P,view=[0..7,8..26]):
display(p1,p2);

-HFloat(17.540266666666668)+HFloat(17.712)*x

  

t    Actual P  Model P  Error

  

Error, (in fprintf) integer expected for integer format

  

HFloat(0.7463867411787324)

  

 
> 

NULL

Download Asst_4_Question_1f.mw

How to create orthonormal triads with "Physics:-Ve...

Asked by: olivier107 10
basis orthonormal physics
October 21 2023
2  0

Hello,
I recently discovered the "Physics" package wich provides tools for manipulating abstract vectors (non-component).
In the "Physics:-Vectors", an orthonormal basis (i,j,k) is available and my main concern is how to generate arbitrary other 3D orthonormal bases to be able to calculate results in "vectorial form" without manipulating vectors' components.

To better explain my needs I have setup a kind of minimal example in the attached file where some questions are asked.

Thanks in advance for any feedback.

orthonormal-triads.mw

NULL

restart

with(Physics)

with(Physics[Vectors])

Creation of 2 rotation matrices

dir1 := `<,>`(0, 0, 1)

dir2 := `<,>`(0, 1, 0)

seq(assign(cat(R, i), Student:-LinearAlgebra:-RotationMatrix(theta[i], eval(cat(dir, i)))), i = 1 .. 2)

print(R1, R2)

Matrix(%id = 36893490614987576012), Matrix(%id = 36893490614987577572)

 (1)

whattype(R1)

Creation of  orthogonal unit "Physics:-Vectors" from previous matrices

x1_ := _i*R1[1, 1]+_j*R1[2, 1]+_k*R1[3, 1]``

y1_ := _i*R1[1, 2]+_j*R1[2, 2]+_k*R1[3, 2]

z1_ := _i*R1[1, 3]+_j*R1[2, 3]+_k*R1[3, 3]NULL

NULL

x2_ := _i*R2[1, 1]+_j*R2[2, 1]+_k*R2[3, 1]NULL

y2_ := _i*R2[1, 2]+_j*R2[2, 2]+_k*R2[3, 2]

z2_ := _i*R2[1, 3]+_j*R2[2, 3]+_k*R2[3, 3]

Q1: Is there a more elegant way of creating "Physics:-Vectors" from matrices ?

Now, suppose that we want to compute `&x`(`#mover(mi("x1"),mo("&rarr;"))`, `#mover(mi("y2"),mo("&rarr;"))`) : since `#mover(mi("y2"),mo("&rarr;"))` = `#mover(mi("j"),mo("&and;"))` we have `&x`(`#mover(mi("x1"),mo("&rarr;"))`, `#mover(mi("y2"),mo("&rarr;"))`) = sin(`#mover(mi("x1"),mo("&rarr;"))`, `#mover(mi("j"),mo("&and;"))`)*`#mover(mi("z1"),mo("&rarr;"))` and sin(`#mover(mi("x1"),mo("&rarr;"))`, `#mover(mi("j"),mo("&and;"))`)*`#mover(mi("z1"),mo("&rarr;"))` = sin((1/2)*Pi-`&theta;__1`)*`#mover(mi("z1"),mo("&rarr;"))` and sin((1/2)*Pi-`&theta;__1`)*`#mover(mi("z1"),mo("&rarr;"))` = cos(theta[1])*`#mover(mi("z1"),mo("&rarr;"))`

The cross product operator  `&x`(x1_, y2_) yields

cos(theta[1])*_k

 (2)

(which is a correct answer) instead of cos(theta[1])*`#mover(mi("z1"),mo("&rarr;"))` because vector `#mover(mi("z1"),mo("&rarr;"))` has is not known as a unit basis vector.

Similarly, `&x`(z1_, x1_) yields -sin(theta[1])*`#mover(mi("i"),mo("&and;"))`+cos(theta[1])*`#mover(mi("j"),mo("&and;"))` instead of  `#mover(mi("y1"),mo("&rarr;"))` as it would be the case when computing `&x`(_k, _i) ?

Q2: Is there a way to declare new triads of "Physics:-Vectors" with properties similar to the provided triad _i, _j, _k ?

Q3: Is the code defining the canonical basis i, _j, _kavailable for inspection and inspiration to setup orthonormal triads ?

Q4: Is it possible to get a (column) matrix of the vector components ? The function Physics:-Vectors:-Component(y1_, n) can only get 1 component at a time and only in the canonical basis i, _j, _k.

NULL

restart

with(Physics)

with(Physics[Vectors])NULL

After a proper definition of 2 new vector bases `#mover(mi("x1"),mo("&rarr;"))`, `#mover(mi("y1"),mo("&rarr;"))`, `#mover(mi("z1"),mo("&rarr;"))` and `#mover(mi("x2"),mo("&rarr;"))`, `#mover(mi("y2"),mo("&rarr;"))`, `#mover(mi("z2"),mo("&rarr;"))`, the position vector OM_ := l__1*x1_+l__2*x2_NULLNULL

l__1*x1_+l__2*x2_

 (3)

NULL

projected on `#mover(mi("x2"),mo("&rarr;"))` would yield directly Typesetting[delayDotProduct](l__1, `#mover(mi("x2"),mo("&rarr;"))`.`#mover(mi("x1"),mo("&rarr;"))`, true)+l__2 instead of expand(OM_.x2_)

l__1*Physics:-Vectors:-`.`(x1_, x2_)+l__2*Physics:-Vectors:-Norm(x2_)^2

 (4)

because of the unit vectors.

Download orthonormal-triads.mw

Bug in simplify piecewise...

Asked by: Rouben Rostamian 8586
simplify piecewise physics
October 20 2023
1  2

This used to work in Maple 2022.  Something is broken in 2023. 

 

> 

restart;
> 

kernelopts(version);

`Maple 2023.1, X86 64 LINUX, Jul 07 2023, Build ID 1723669`

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1561 and is the same as the version installed in this computer, created 2023, October 20, 22:58 hours Pacific Time.`

> 

U := Int(exp(-1/4*t - 1/4*x)*piecewise(x < -2, 1, x < -1, -x - 1, 0), x = -t .. 0);

Int(exp(-(1/4)*t-(1/4)*x)*piecewise(x < -2, 1, x < -1, -x-1, 0), x = -t .. 0)

> 

Uval := simplify(value(U));

Uval := `simplify/piecewise/unfactor`(4*piecewise(t < 1, 0, t < 2, t-5+4*exp(`&ndash;`((1/4)*t)+1/4), 2 <= t, 1+4*exp(`&ndash;`((1/4)*t)+1/4)-4*exp(`&ndash;`((1/4)*t)+1/2)))

> 

eval(Uval, {x=5, t=6});

`simplify/piecewise/unfactor`(4+16*exp(-5/4)-16*exp(-1))

> 

 
 

Download simplify-piecewise-bug.mw

 

Inverse Laplace transform on Maple 2023 broken...

Asked by: Rouben Rostamian 8586
inverse laplace
October 19 2023
2  10

Maple thinks the inverse Laplace transform of 1/(s+a) is exp(a*t).  It should be exp(−a*t).

This used to work correctly in Maple 2022.  Something got messed up in 2023.

> 

restart;
> 

kernelopts(version);

`Maple 2023.1, X86 64 LINUX, Jul 07 2023, Build ID 1723669`

> 

with(inttrans):
> 

exp(-a*t);

exp(-a*t)

> 

laplace(%, t, s);

1/(s+a)

> 

invlaplace(%, s, t);

exp(a*t)

 

Download laplace-transform-bug.mw

Plotting a function with factorials. Why does this...

Asked by: Scot Gould 1039
plot plotting factorial
October 18 2023
2  10

This is not a critical situation. A solution was developed. However, I am interested in trying to understand and explain to a colleague why their function failed to plot. The colleague often works on problems involving large factorial values.

failed_plot.mw

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