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Hi,

 

I want to calculate a new position (X,Y,Z) for a cartesian model with 3 points (dX,dY,dZ) but  I got a problem, my point is a parameters, so I can't change it in the simulation in real time with a Input signal on the components. Does It exist a solution for convert a parameters to a variable to get a Input signal?

Exemple of my calcul:

eq:= [x(t)= dx+sin(dy/dz), y(t)=dy+20,z(t)=dz]

 

Thanks!

Hi.

I am new in Maple and I'm trying to get functions from system of equations.

Constants are defined in line 4 and equations are:

eq1 := E2 = fE2(1+(KaE2+Ca)/(1+KaE2*fE2+KaT*fT+KaDHT*fDHT)+KsE2*Cshbg/(1+KsE2*fE2+KsT*fT+KsDHT*fDHT))

eq2 := T = fT(1+KaT*Ca/(1+KaE2*fE2+KaT*fT+KaDHT*fDHT)+KsT*Cshbg/(1+KsE2*fE2+KsT*fT+KsDHT*fDHT))

eq3 := DHT = fDHT(1+KaDHT*Ca/(1+KaE2*fE2+KaT*fT+KaDHT*fDHT)+KsDHT*Cshbg/(1+KsE2*fE2+KsT*fT+KsDHT*fDHT))

KsT = 0.10e11; KaT = 4.6*0.10e6; KsE2 = 3.14*0.10e10; KaE2 = 4.21*0.10e6; KsDHT = 3*0.10e6; KaDHT = 3.5*0.10e6;

fT, fE2 and fDHT are variables, not functions (i.e. fT is not f(T) ) and I am trying to get fT=f(E2,T,DHT,Ca,Cshbg), fE2=f(E2,T,DHT,Ca,Cshbg) and fDHT=f(E2,T,DHT,Ca,Cshbg).

When I type:

eliminate({eq1, eq2, eq3}, {fE2, fT, fDHT})

Maple gives me a blank field. No error, no other comment.

I have no idea where I'm making mistakes.

Any suggestion is appreciated.

 

Thanks in advance.

restart;
k:=1;
sum(k^2,k=1..10);
      (in sum) summation variable previously assigned, second argument

gives an error, since k is not free. Fine. No problem. But add() has no problem with an assigned variable:

restart;
k:=1;
add(k^2,k=1..10);

and seq() has no problem either

restart;
k:=1;
seq(k^2,k=1..10);

It is confusing when learning Maple since it does not seem to behave the same way in all its functions. What is the reason for this design? 

Hello, everyone.

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

 

Thanks!!

I'm having some trouble maybe someone can point out my error please. I'm using the Maple 18 worksheet to try some basic linear equations. The trouble is in the last step.

 

1.) I start with 2 ordered pairs (2, 14) and (14,18)

Then I put in my formula to discover the slope. I confirm it looks correct in the Variables window.

m := (y2-y1)/(x2-x1);

 

2.)  Next I input the values for my ordered pairs. I also confirm thru the Variables window.

x1 := 2;

y1 := 14;

x2 := 3;

y2 := 18;

 

3.) Now I can type m and expect to get an answer to what my slope is.

m;

4.) Now I want Slope/Intercept form of y=mx+b. When I put in the formula y-y1=m(x-x1) i get a strange result

 

When I execute this formula, the result is y-14=4. (or thru context menu I tell it to solve for y, then I get y=18)

y-y1=m(x-x1) 

When I manually input the values, the output is y-14=4x-8 (or thru context menu I tell it to solve for y, then I get y=4x+6)

y-14 = 4*(x-2)

 

 

 

Why is my equation (y-y1=m(x-x1)) not executing properly?

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 am new user of Maple. I have an expression like f(x,y)/g(x,y) and I want to have Maple name f(x,y) as something simple like "h" so that later equations write h/g(x,y) instead of the complete f(x,y)/g(x,y), and also to be able to simplify other equations in terms of h.

For example, a=(x+1)(y-5)^2/(x+y-3). Can I get Maple to let h=(x+1)(y-5)^2, so that I get h/(x+y-3) when I ask for a?

Sorry if this question is basic (and my math terminology incorrect), but I have been trying for a while.

Hello,

sometimes I observe extreme delays when simply entering a variable name like fooBar; right after starting a Maple session. This happens when the current directory contains a file with that name, because Maple automatically loads this file.

For example, if I create an empty file fooBar.m and start a Maple session,

> fooBar;
Error, `./fooBar.m` is an incorrect or outdated .m file

raises an error. More often however, I have some huge Maple files in the working directory and whenever I use (by chance) a variable name in the Maple session that matches a filename, Maple tries to load the corresponding file.

Is there a documentation of this behaviour and a possibility to stop this automatic loading of files?

Thanks,

Erik

Hi,

I'm new here and I couldn't find similar problem in this forum.

I want to use variable (red marked) with unit definite integrals but it doesn't work. I put the file with units and file without units (to check correct solution) in this post.

What to do?

Files:

01_referat(units).mw

01_referat(without_u.mw

I'd expect the following to give the result "c+2".

> c := a+b

> simplify(a+b+2)

How can I let Maple know that I'd prefer it to write "c" in place of "a+b" when possible?

I need to get rid of the type "constant" for gamma. In Maple, gamma is defined as Euler's constant by default. While it is easy enough to unprotect(gamma) and then get rid of its value, Maple will refuse to solve an equation for gamma, as it remains of type constant even after deassigning it. So I need to regain gamma as a variable.

Some may feel this is an unwise thing to do. But it actually is not: I am writing a document involving physics, and gamma is the accepted symbol for the relativistic energy. I cannot avoid using that, lest mass confusion ensues (this involves students). I really don't want to write gammar instead. Euler's constant, otoh, does not figure at all in my document.

Note that I need a solution that works in Maple 15 and later as I am working in a heterogeneous environment as far as Maple versions are concerned.

Thanks in advance,

Mac Dude

 

How to calculate c.d.f from probability mass function. Suppose that the pmf of a discrete random variable is given : f(x)=(2*x+1)/25, x=0,1,2,3,4

It seems Maple has no Clear(variable); function build in, and one must type

         variable := 'variable`; 

for each variable to be cleared. This is a little too verbose. In Mathematica one types "Clear[variable1,variable2]" which requires much less typing than the Maple way of doing it. (About 1/2 as much, if one has to clear few variables each time).

Doing restart is not a good solution all the time, since that will clear everything.

Strange why Maple can not provide such a function, and inside it, it can do these calls.

So, I was wondering if someone has written such a function. I can try to write one myself, but I am not very good in Maple, and I think a professionally written one by an expert would be more robust and will do more checking as needed to make sure it works correctly.

So, my question is, why Maple does not provide such a function as build-in? And does one know of a good implementation of one that exist?

How do I define a function from a graph in a plot? 

Or how do I find the intersection between two lines? I have to find the intersection of 2 lines in a graph, while one of these lines consists of 2 different equations dependent from the same variable. 

 

Thanks in advance. 

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