Items tagged with define define Tagged Items Feed

I know how we can add a member to a mathematical set ,for example :

C := NULL;

C := C, V, B, X;


V, B, X

but, my problem is that how we can subtract a member from the defined set ?





Hello, i got the following problem. I have a function, say u(h,e) whith multiple exponents ((u(h,e))^(1/a))^a. As long as Maple does not know that u(h,e) is positiv it won't make the simplification and return u(h,e) as expected. From my view i have two possibilites to solve this problem:

1) Define u(h,e) to be positive. Sounds intuitive, but i didn't manage to find the right definition

2) Give maple the function e.g. u:=e+h^2 and simplify the epression in uneval quotes with assumption positive for e and h.

Whereas I have solution 2, the problem is that i would need excessive amounts of uneval quotes '' at the start of my worksheet, not to run out of them.


I definitly need my epressions in unevaluated forms and would be happy to hear any ideas.

Greetings, Fabian



I'm trying to define a matrix that will have all the possible game results in a 9 team competition in one round. The results are a column in the form [game 1 home team, game 1 away team, game 2 home team, ... , game 9 away team]

This should give me a matrix with 18 rows, and 512 columns, where each column is a possible game result.

In essense, to continue the pattern of this matrix on for all 512 columns.

I've fiddled with for statements, but it ends up getting very messy given the number of nests that are required.

Thoughts? Any help would be much appreciated,

Thanks, Alex, Australia.







Is it possible to define and use an abstract linear operator L which is a function of y(x) and z(x)? 

For example, Maple should be able to recognise that L(y(x),z(x)) = L(z(x),y(x)) and simplify expressions such as 

L(c*y(x),d*z(x)) = c*d*L(y(x),z(x)) where c and d are constants or numbers.

It should also be able to expand things like L(c*y1(x)+d*y2(x),e*z1(x)+f*z2(x)).


Let a be som expression like

Now how do I define a function using a.

doesnt work


I have this MATLAB script, but as I work in Maple, I'll need to translate it to Maple. 
I know how to define symbols and functions, but I don't know which Maple commands to use, of if it needs to be done in another way, so the problem is translating from " dZ = [dx; dy; ax; ay; dm];" and down.

Any help would truly be greatly appreciated! Thank you!  

This is the script:

function dZ = meteor_step(~, Z)

  P = 1.2; % initial atmospheric pressure
  H = 1.39E-4; % scale height of atm pressure
  E = 8.11131859E6; % evaporation energy
  D = 1; % drag constant
  G = 9.814; % acceleration due to gravity
  PM = 3.3E3; % density of the meteor
  S = 3.986E14; % standard gravitational parameter of Earth (G*M)
  R = 6.3674447E6; % radius of the Earth (meters)

  x = Z(1);  
  y = Z(2);
  dx = Z(3);
  dy = Z(4);
  m = Z(5);
  atm = P*exp(-y*H);

  v = sqrt(dx^2+dy^2);

  area = pi * ( (3*m)/(4*PM) )^(2/3);

  dist = sqrt(x^2+y^2);
  Gv = -9.8;

  accel = -(D*atm*area)/m*v;
  ax = accel * dx;
  ay = accel * dy + Gv;

  dm = -(atm*v^3*area)/(2*E);
  dZ = [dx; dy; ax; ay; dm];





[t, R] = ode45(@meteor_step, [0 250], [0, 100000, 100, -300, 25]);

x = R(:,1);
y = R(:,2);

dx = R(:,3);
dy = R(:,4);

v = (dx.^2+dy.^2).^(1/2);

m = R(:,5);

plot(t, y);
  title('Meteor Kinematics: Height vs Time');
  xlabel('Time elapsed (s)');
  ylabel('Height (m)');

plot(x, y);
  title('Meteor Kinematics: Horizontal vs Vertical Position');
  xlabel('Horizontal (m)');
  ylabel('Vertical (m)');

plot(t, v);
  title('Meteor Kinematics: Speed vs Time');
  xlabel('Time elapsed (s)');
  ylabel('Absolute speed (m/s)');

plot(t, m);
  title('Meteor Kinematics: Mass vs Time');
  xlabel('Time elapsed (s)');
  ylabel('Mass (kg)');

plot(t, dy);
  title('Vertical Velocity vs Time');
  xlabel('Time elapsed (s)');
  ylabel('Vertical velocity (m/s)');

temp = abs(y - 52900);
[~, index] = min(temp);

Dear people in mapleprimes,


>define(INT, linear, conditional(INT(a::algebraic, X::name) = a*X, _type(a, freeof(X))), INT(X::name, X::name) = (1/2)*X^2);

>INT(2*x+4, x);

x^2 + 4*x

>INT(z+x, z);

(1/2)* z ^2+ x*z

is written in the help page of maple.

This code is to make a function INT.

What it means is that if INT(a::algebraic, x::name) then this is transformed into a*X, where a is independent from x.

And, INT(X::name,X::name) is transformed into (1/2)*X^2.


The first of what I want to ask you is the way of use of "_type", which is not in the help page, and as for names with "_" ahead, 

it is written that "_" means internal command for Maple, so not to use it. Is it right to use a name with "_" ahead of it here?

The second of what I want to know is the way to use "conditional."

Please teach me the meaning of this.

Thanks in advance.


I hope you will teach me the above questions.


Best wishes.





Hi every Body?

I will define the function f(t) in maple,how?

f(t)=1-t for 0<t<10 and t for t>10

Hi everyone,

I have a question regarding the derivation of tensors/matrices.
Let's assume for simplicity, that I have a vector (6x1) s and a matrix A (6x6)defining Transpose(s)*Inverse(A)*s. From this function I want to calculate the derivative w.r.t. s. My approach would be


Transpose(s)*Inverse(A)*s, s)

As a result I get

though I'd rather expect something like Inverse(A)*s + Transpose(s)*Inverse(A)

Now as I'm pretty new to Maple, I can imagine that my approach is wrong, but I don't know any better and can't seem to get any information out of the help documents.

Thanks in advance for any of your suggestions!

Hello, everyone.

There are two variables: n1 and n2, how to define n1+n2=1 (not n1:=1-n2).



the question


I already finished part a, my question is how do i define the function g with the variable k being any real value so that maple will find <f,g> = 0 (using the inner product defined)?


This has been buggin me all day, but if i define a variable with an expresion say "a:=3 x+5" and i then want to assign this expression to a function like so "f:=x->a". if i then call f(7), maple return with "3 x+5" so just returning the value of a without substituting x with 7.

Is there any way in which i can define a function this way?

I want to define the budget set of a consumer, which consists of an horizontal, slant and vertical line segments. How can I define and plot the budget set?

Hello Maplers, i have encountered a little annoyance with Maple, that i would like to ask, whether it can be solved. 


It's when i try to define a function, like f(x)=2x and try to define it with a command f(x):=2x, a pop-up box comes up, asking me whether i'd like to use a 'function definition', or 'remember table assignment', and i would like to make Maple remember my choice that i want a function. 


I know i can write it like f:=x->2x, but i hate to look at that, to be frankly..


So, is there any way to solve this?


1 2 3 4 Page 1 of 4