In our assignments students may may make the questions and grade four times (the number of attempts is set to 4). Unfortunately the review feedback button has disappeared, so that students are not able to know which questions were still incorrect.

The policy is exactly the same as in previous assignments and in those the review feedback button always appeared.

Does any one know what is wrong, and more importantly how can I correct this problem?

kind regards,

Harry Garst (troubled instructor)

 

Hi

I use a loop to fit a model to several different datasets, loading and storing for each dataset several matrices and graphs. It seems that the calculations get slower and slower the more the loop progresses and sometimes the run just crashes. I assume this is due to the large amount of data stored in Maple's memory. Is there a way to empty the memory after I've exported or saved the matrices or graphs?

Thanks, Marjet

Does anybody happen to know how to get maple to do something of this form:

evalf(Int(fsolve(f(x,t)=0,x),t=0..1)).

I get the error message "Error, (in fsolve) t is in the equation, and is not solved for" .

Thanks

Is that a bug?

For example, a simple expression like so ...

a:=b=3*x+5;

solve (a,x);  will return solve (b=3*x+5,x)   Not exactly what one was looking for.  Removing the space, solve(a,x) and now it will work exactly like you wanted it to. 

I can't recall wether I read somewhere that spaces weren't allowed.  That true?  Or do they need to brush up on the next update?

 

 

Hi all,

I have the following:

Does anyone know if it is possible to use RegSubs within Maple TA?
For example

StringTools[RegSubs]("([0-9]),([a-z])"="\\1*\\2", "2x*3y");
 

cf  www.mapleprimes.com/forum/weird-regsubs

 

 

We have an assignment that is now "closed" so further student work on it is impossible.

We would like to extract final results, but can't force grade all the remaining assignments because a handful of students are logged on and so (even though they can't be doing this assignment), this assignments can't be force-graded.

Is there some way round this, or is this another design flaw and we just have to keep on force-grading until we catch them all offline?

Toby Bailey

 

How do I define an expression?

I have a system of two ODE's. One is of the form dT/dt=a*(dc/dt)-b, where a and b are constants. The other is of the form dc/dt=-(c^2)*d*exp(j*(1/T-1/k)), where d,j, and k are constants. I need to find the maximum value for T. I can solve dT/dt via the separation of variables method to get and expression T=f(c,t). I then substituted this expression into dc/dt=f(c(t),t) and solved it numerically in Maple. How do I substitute the values of c(t) obtained in Maple into T=f(c,t) and find the maximum? Or is there a better method?

I'm trying to use Maple to solve an ODE instead of using partial fractions.  I can't get the syntax correct.  The original problem is...

 

dC = C(1-0.0002C)dt        C(0) = 2   for t >0

 

I know it's seperable into

         dC             = dt

C(1-0.0002C)

 

I can't get anywhere to find an explicit form!  Any help is appreciated :D

I want to open a file, in maple.  I do not want to open maple, and then open the file. 

More specifically, how do I

a) run something like:

maple -x -f myfile.mw

so that xmaple starts and opens directly to the file myfile.mw.  Ideally if xmaple is already running, it will hopefully just spawn a new tab.

b) set this up as a "Preferred application" in Fedora and in Ubuntu.

I think a) may solve b).

 

How could I obtain the 2 values (a, b are reals) of this complex number?

I tried

assume(a::real)

assume(b::real)

sqrt(a+i b)    and     (a+i b)^(1/2)  give back the input.

Thanks,             Sandor

Given several poins and a known center, how do I approximate a circle with an unknown radius with Maple?

I am totaly new using this software, so I don't know how to start.

Thank you for your help!!

I have the equation of a sphere x^2+y^2+z^2 = 36 and two points in three space P(-3,-10,2) and Q(5,14,8) and I need to show that the line between the points intersects the sphere graphically and analytically, but I cant even figure out how to graph them, and I have a suspicion, but am not sure, that to prove it analytically I would find the equation of the line in three space between the points and prove that the line equals the equation of the sphere in two places, but I cant figure out how to find that equation either.

Each line in my data file reads

[elm1, elm2, elm3, elm4]

I have the following lines to tally column 1:

> data:= map2(op, 1, datafile);

> Statistics[Tally](data);

I would like to tally the 3-tuples, [elm1,elm2,elm3], and it doesn't seem that Tally is able to handle a 3-tuple. 

I appreciate any help you can offer.