Maple 2019 Questions and Posts

These are Posts and Questions associated with the product, Maple 2019

Hi!
I am trying to solve ODE with bvp[midrich], and I need to prove the validity of this method. 
Where can i read about realization of bvp[midrich]. What scheme does it use? Аre there any articles on this subject?
 

 

In Maple 2019.2, I'm trying to compute series expansions. For the input
series(1/z^4/(1-z), z=0, 1);
Maple gives me a series of the expression around z=0, truncated to 1 term, i.e.
z^(-4) + O(z^(-3))

But with the input
series(1/z^4/(1-z), z=0, 2);
Maple gives me the result
z^(-4) + z^(-3) + z^(-2) + z^(-1) + 1 + z + O(z^2)

Apparently Maple has decided not to give a series with 2 terms, but a series up to O(z^2). I'm surprised that the third argument of "series" is not treated in a consistent manner. I've restarted the Maple server between the two computations, so it's not a memory effect.

In the above example, this is just a minor annoyance, but I'm actually dealing with huge expressions, and for performance reasons it's important to truncate the series expansion at the desired order and stop further computations. Has anyone encountered this problem?

Can Maple solve a (simple) nonlinear diophantine equation with restrictions on the variables?

For example, I would like to solve simple equations where all values of the variables are positive integers.

I have tried isolve. For example:

isolve({29 = x^2 + y^2, 1 <= x, 1 <= y})

and

{isolve}({29 = x^2 + y^2, 1 <= x, 1 <= y})

but they just give a warning (and no solutions):

Warning, solutions may have been lost

 

Does anyone use a windows 10 code editor like, emacs, vim, or other with good textual layout, error and type checking? for building procedure files (libraries)?

 

I am using Maple2019.   I have been using a code region started in a worksheet and then exported to mpl file.   Not sure if I have really seen a debugger with breakpoints, step-in/step-out, type checking?   Am I just not looking in the right area?

 

Best practices from programmers of maple procedures appreciated.

Bill

 

Hi, I have a problem that needs excessive use of symbolic matrix-vector manipulation. I'm using maple physics vector package. my first problem is that it seems this package don't support symbolic vector transpose and the related rules is there a way to implement this, for example, I want to write in symbolic form: V_*Transpose(V_) but maple eliminate the Transpose head function and evaluate this as V_^2 which is wrong, or I want maple automatically simplify the transpose rule which state that (ab)'=b'a' which a and b are symbolic matrices if maple doesn't understand this, so is there a way I can implement this.
my second question is how can I state that for example, A*B is not equal to B*A with just assuming A and B are Matrix with Airbtrary dimension and not define A and B indices so that whenever i type: A*B+B*A it doesn't evaluate it as 2*AB

How to do this in Maple please?

Iterate an array and select x items so that the sum of the selected items equal or are above a value.

Eg. 10 real numbers in an array, random for example between 0..10 and select some of them so the value is equal or greater than y, e.g 5.2 , as close as possible to optimize the selection.

This is my attempt to produce a subplot within a larger plot for magnifying data in a small region, and putting that subplot into the white space of the figure.
Based on the questions: How to insert a plot into another plot? and Inset figure in Maple, I wrote a couple of procedures that create sub-plots and allow the user to place the subplot window as he/she chooses. This avoids the graininess issues mentioned by acer in the second link (and experienced by me).

So far, I only have this completed for point plots, but using acer's method of piecewise functions posted in the plotin2b.mw of the second article, with the subplot function being defined only if it satisfies your conditions, would allow the subplot generating procedure to be generalized easily enough. But the data I'm working with all point plots, so that's the example here.

The basic idea  is to use one procedure to create boxes, make tickmarks on the expanded region, and make tickmark labels, combine all of those into one graph. Then create scaled and shifted versions of the data series, then make graphs of those. Lastly, combine them all into one picture.

Hope this helps someone who has to do the same.

Mapleprimes isn't inserting the contents, but here is the download of the file: SubPlotBoxesandVectorDataSeries.mw

 

I want to plot y=sec(x) and x=-pi/4, x= pi/4. I also want the bounded region shaded. I have been able to graph sec(x) but I can't figure out how to get the two vertical lines and the bounded region shaded.

I'm having problems with Multiplying Complex Numbers in Maple 2019.

Thanks in Advance.

Example 2: Multiplying Complex Numbers

 

(2-i)(4+3*i)

(3+2*i)(3-2*i)

4*i(-1+5*i)

(3+2*i)^2

2-i(4+3*i)

 

3+2*i(3-2*i)

 

4*i(-1+5*i)

 

(3+2*i)^2

(1.1)

``


 

Download Multiplying_Complex_num.mw

How I can plot the answers obtained from solving two differential equations?

Thanks

SAL.mw
 

restart

e := 0.62e-2

0.62e-2

(1)

r := 0.15e-1

0.15e-1

(2)

DDo2 := .17*3600

612.00

(3)

DDco2 := .12*3600

432.00

(4)

NULL

N := 20

20

(5)

P1o2 := 3600*(1000*(27*10^(-13)*24.45)*100)/(10000*0.986923267e-2)

0.2408029155e-3

(6)

P1co2 := 3600*(1000*(99*10^(-13)*24.45)*100)/(10000*0.986923267e-2)

0.8829440235e-3

(7)

P2o2 := Pi*r^2*DDo2*N/(e+r)

408.1106684

(8)

P2co2 := Pi*r^2*DDco2*N/(e+r)

288.0781188

(9)

diff(y[o2](t), t) = ((P1o2+P2o2)*(21-y[o2](t))-100*(167*y[o2](t)/(1.6+y[o2](t))*.25))*(1/1300)

diff(y[o2](t), t) = 6.592560841-.3139314686*y[o2](t)-3.211538462*y[o2](t)/(1.6+y[o2](t))

(10)

diff(y[co2](t), t) = ((P1co2+P2co2)*(0.4e-1-y*y[co2](t))+.25*(.8*(167*y*y[co2](t)/(1.6+y*y[co2](t))))*100)*(1/1300)

diff(y[co2](t), t) = 0.8863969285e-2-.2215992321*y*y[co2](t)+2.569230769*y*y[co2](t)/(1.6+y*y[co2](t))

(11)

                 initial*conditional     @t=0     yO2=21 , yco2=0.04


 

Download SAL.mw

 

Hello, so my maple won't solve any function involving either cos, tan or sin. Has anyone experienced this before or know how to fix it? 

For example i need to find: cos(30), but it comes up as cos(30) after I hit enter. 

 

Many thanks to anyone who tries to help! :)

how I can I get MAPLe to simplify this to Pi/2-beta ,

simplify(arctan(sin(beta)/cos(beta)),arctrig) assuming beta<Pi/2,beta>0;

simplify(arctan(sin(beta)/cos(beta)),symbolic) assuming beta<Pi/2,beta>0;

why i can't get Pi/2-beta

https://www.mapleprimes.com/questions/219048-Help-File-Edit-After-Storing-In-A-Database

I found a previous post which contained a worksheet script for creating help, but this example is likely out-of-date. Can anyone provide a similar example for post-2018 help files to save me considerable trial and error.

Hi, I am a beginner of maple and I met a problem recently.

I extracted some equations from a .txt file like below:

> read “D:/blablabla/filename”

                       EQ_1,EQ_2,...

Then I want to collect all these equations to make a list EQlist=[EQ_1,EQ_2,...] but the following code doesn't work:

> EQlist:=read “D:/blablabla/filename”

Error, invalid assignment

Could anyone tell me how to construct such EQlist?

Thank you in advance.  P.S. I can't just copy and paste because these commands are supposed to be in a loop.

Is this a bug?

eq:=5*x+y-10=0:
eq2:=y=solve(eq,y):

f:=(x,y)->eq2
                              
f(3,1)
                   

I think the way I applied it above is a bit unorthodox to Maple but maybe it is a bug.  Normally I think we use unapply in this situation. 

f:=unapply(eq2,x,y)
                             
f(3,1)
                     

Okay better, but I think that first way should work no?

 

First 16 17 18 19 20 21 22 Last Page 18 of 45