print(`output redirected...`); # input placeholder
   d ph                                                     
   ---- = (1 - yc) pc + yh prj + urd prd + ugd pgd - yc ph,
    dt                                                      

     d pc                        d pa               
     ---- = yc ph - (2 - yc) pc, ---- = pc ya - pf,
      dt                          dt                

     d prj                 d prd                     
     ----- = pa yrj + prj, ----- = pa yrd - prd urd,
      dt                    dt                       

     d pgd                     
     ----- = pa ygd - pgd ugd,
      dt                       

     d pf                                          
     ---- = (1 - ygd - yrj - yrd) pa + (1 - yh) prj
      dt                                           
ics := ph(0) = 1, pc(0) = 0, pa(0) = 0, prj(0) = 0, prd(0) = 0, pgd(0) = 0, pf(0) = 0;
print(`output redirected...`); # input placeholder
   ph(0) = 1, pc(0) = 0, pa(0) = 0, prj(0) = 0, prd(0) = 0,

     pgd(0) = 0, pf(0) = 0

i write this equations in maple

but i get this error

Error, (in dsolve) ambiguous input: the variables {pa, pc, pf, pgd, ph, prd, prj} and the functions {pa(0), pc(0), pf(0), pgd(0), ph(0), prd(0), prj(0)} cannot both appear in the system

can anyone help me?

Could someone help me understand what is happening to this procedure. When I run it, I get the subject error. Thanks.

game := proc()
  local player1, player2, roll;
  roll := rand( 1..6 );
  player1 := roll():
  player2 := roll(2):
  if player1>player2 then "A wins"
  elif player1=player2 then "Tie"
  else "B wins"
  end if;
end proc:

Dear friends.

I need a simple approach for reading a specified line of a text file.

FileTools[Text] module allows to count the lines. By sequential reading of lines it's possible to reach any position in the file. But for large file this takes a lot of time.

FileTools[Position] allows to set/get position in the file, but the position is counted in bytes.

Are there any workarounds for the problem or the use of Database Package is more preferable?

This might seem easy but i am a total beginner in Maple and i really need to know how to do this. If i have an expression like this:

X^2 + 3*y + 3*z + X^7

where (y) and (z) are constants of unknown values. I need to integrate the expression over an interval for example (from 1 to 10) so that the answer would still be in terms of (y) and (z).

Would anyone please help me and give me the right expression for writing this on Maple?

Thanks in advance.

In case anyone is interested, we recently posted a new application on the Application Center,

Time Series Analysis: Forecasting Average Global Temperatures

While interesting in itself (well, I think so, anyway), this application also provides tips and techniques for analyzing time series data in Maple, and shows how to access online data sets through the new data sets functionality in Maple 2015.

eithne

I'm looking at Maple as a possible alternative to Mathcad (which I've been using for years, but is now very jaded compared to other options like Maple and Mathematica).  I'm a civil engineer and for what I do, one of the better features of Mathcad is the way it handles units.  For example, if I specify an angle in degrees (say phi=30 degrees) and then ask for sin(phi), I get 0.5.  At face value, I though Maple would do the same kind of thing.  However, this doesn't appear to be the case (see attached worksheet).  The only workaround that I can see is to specify the angle in degrees (but without assigning ) and then multiply the specified value by pi/180 (to convert to radians) before passing it to the sin function.  Which is all a bit messy and not at all an attractive solution.

Am I misunderstanding the way units work in Maple and is there a clean way of specifying angles in degrees (which is what engineers work with) and using these values directy in trig functions?

Thanks in anticipation,

Ian

I am very new to Maple and am wondering how i would install a package. The package I am trying to install is located at

http://math.rutgers.edu/~russell2/papers/IdentityFinder 

I am using Maple 2015 on windows 8. Any advice would be useful

Hi everyone!

I use two "ArrayTools:-Copy" commands to copy elements from Vector A to Vector B.

restart;
A := LinearAlgebra:-RandomVector(10); A := convert(A, Vector[row]);
B := Vector[row](10); ArrayTools:-Copy(2, A, 1, B, 1); ArrayTools:-Copy(2, A, 7, B, 7); B;

My question is: Could I obtain the same result using only one command?

P.S. I tried to use "ArrayTools:-BlockCopy", but didn't get correct result.

I want to retrieve all the commands input by user in a maple document saved on disk. How this can be done? DocumentTools:-Retrieve permits to receive only the labeled expressions but not the input commands.

Maple function plot allows to build a linear plot for two vectors, when one vector contains X coordinates, another -- Y coordinates (similar to plot below):

Is it possible to build such a plot for several Y-vectors like this:

Some of the Rotation Coefficients are not calculating properly.

Question_about_Ricci_Rotation_Coefficients.mw

Hello,

I wonder if it is possible to create standalone executables in Maple that would run in a  computer without Maple. Also if it is possible can we do that with Matlab code in it too?  

Matlab does not allow to create standalone executable is you use symbolic toolbox and I want to find a solution for that. What I will need to take second derivatives and get the coefficients of polynomials. 

hi, the equations read as 

eq:=[2*x-0.2e-1*y-2.04*sqrt(-v^2+1)*v, 2*y-0.2e-1*x-2.16*sqrt(-u^2+1)*u, 2*u+2.16*u^2*y/sqrt(-u^2+1)-2.16*sqrt(-u^2+1)*y, 2*v+2.04*v^2*x/sqrt(-v^2+1)-2.04*sqrt(-v^2+1)*x] ;

i do as follows using DirectSearch package v.2

i find the solutions not the same,some time the results not much difference,but another,sols1 have one solution,sols2 have three solutions.in some time,some solutions are lost，the result show  me  random.may i have run the command serveral times? regards.

Why does Maple 2015 solve this very simple system incorrectly?

solve({abs(a-b)=0, sqrt(2*b+c)=0, c^2-c+1/4=0});

With Maple 12 no problem:

solve({abs(a-b)=0, sqrt(2*b+c)=0, c^2-c+1/4=0});

With this application we can meet safety characteristics of a relationship and simple or compound functions. Made with maple 2015.

Relaciones_y_Funciones.mw

(in spanish)

L.AraujoC.