Is there a 'search and replace' method to replace all comma´s by dots (as a decimal seperator). For example 0,78 into 0.78. At this moment several students responses were graded as incorrect while the only error they made was to provide a response using a comma instead of a dot. I can export the data file and use another program to score the responses, but there may be a much more efficient method to modify the responses.
Harry Garst

Hi guys,
I need to simplify tedious expressions involving products of fermionic creation/annihilation operators.
I loaded the Physics package,
and defined the fermionic operators c[i,spin] and C[i,spin] where i=1..4, spin=1..2
My first concern is that c[i,spin].c[i,spin] doesn't return 0,
while AntiCommutator(c[i,spin],c[i,spin]) does...
I don't get it.
Although when I apply c[i,spin].c[i,spin] to some ket it does return 0...
I'm a bit lost.
Any idea?

All
I have a simple Alternating Series - that will not come up with a convergent result in Maple 11.
Here is the problem ...
Is ... this alternating series convergent or not ?

sum((-1)^n/ln(n), n = 2 .. infinity)
Application of the Alternating series test says YES ... but Maple does not give a result.
Thanks,

donnie

*
LINK to example file with Alternating Series test showing convergent test to be positive. *
So I get this to calculate correctly:
sum(1/n, n = 2 .. infinity);
And the result is infinity - which is obviously correct.
but the following does not give me a result ...
sum(1/ln(n), n = 2 .. infinity);
what is the trick - do i need to assume something here ?
thanks,
dp

I am solving a constrained maximization problem using the Lagrangian and getting back an empty set of solutions, i.e.:
solns_LSW:=
How do I go about diagnosing why Maple is having difficulty finding solutions?
(Once I know that, I would of course also like to know how, if possible, to change the set-up so that Maple might actually find the solution(s)!)
I can see that the Lagrangian becomes non-concave for cases where lambda2>p (p is one of the variables I am solving for: there are two, s and p -- see attached worksheet).
This would clearly be the case for, say, p=0 optimal (which I have reason to believe it is, based on some numerical simulations I ran).

Dear all,
In the attached file I try to solve expression Y for p.
As Y includes dCS(p)/dp, the solve command produces an error message. I do understand that Y can't be solved for p since expression dCS(p)/dp is not fully defined. However, the result I am aiming for is simply: p = -(1/2)*(dCS(p)/dp) (with p simply being a funtion of dCS(p)/dp)
Which command leads to this result? I haven't found it in the help section.
Many thanks for your help!
Florian

View 5919_Question_solve
Hello everyone,
I was wondering if the grid resolution for "patchedcontour" wireframe 3d plots is adjustable? The only setting I know of is 'numpoints', and I can set that to a high number to get a better looking 3d plot, but this results in a dense amount of wiring for the plot. So I was curious if there is a way of getting the 'better' look for a graph while keeping the number of wires low enough so that contours are easily visible (and usable).
Any takers?
Thanks in advance. :o)

I have been told my code is not 'perfect', I'm not too hot on maple and it has taken me a week to get to this stage. Any help or suggestions would be very welcome!
h:=0.1: k:=0.001: r:=k/h^2:
xl:=0: xr:=1: # left and right ends of interval in x
nxpoints:=round((xr-xl)/h):
ntsteps:=5: # total number of time steps
iprint:=1: # print output every iprint time steps
printf(cat(" x,t ","%7.3f"$(nxpoints+1),"\n"),seq(i*h,i=0..nxpoints)):
format:=cat("%7.3f"$(nxpoints+2),"\n"): # format for printing output
Boundary conditions
for j to ntsteps+1 do
u[0,j]:=0: u[nxpoints,j]:=0

hello all ... peculiar problem here ... please help
the expression is true that 1/n(n+1) = 1/n-1/(n+1)
since 1 = n + 1 - n gives 1/n = (n+1)/n - 1
Is there a way to demonstrate this identity in Maple ? ?
I cant find any trick with "expand" or such that works.
This impact is also seen when evaluating ... the following ...
sum(1/n-1/(n+1), n = 1 .. infinity) = 1;
=
print(`output redirected...`);
i get the proper answer of 1
but no answer with :::

I know maple has two functions max and min to compute
the maximum and minimum of some arguments.
But I have a list,such as l:=[1,2,3];
when I use the maple function min，I need to write: min(l[1],l[2],l[3]);
How can I simplify the expression?
If l is list with too many items,how to use min to calculate the minimum?

I need to make a list of 12 random integers from 0 to 1. Take the sum of those values and subtract 6. I have that part....now the part I don't have is how do I run that 10^6 times and keep track of my values?
with(RandomTools):
with(stats):
with(ListTools);
> L := seq(Generate(integer(range = 0 .. 1)), i = 1 .. 12);
1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0
>
> G := add(i^2, i = L);
9
> Z = G-6;
Z = 3
That is my program so far. Any help is appreciated.

Does anyone know if there is a way to obtain the coordinates of an ordered pair on a graph? I see that Maple states the ordered pair your cursor is currently situated at, but what I want is to 'grab' these coordinates and use them in other calculations. Essentially what I want is a Maple command similar to ginput on Matlab. Thanks.

> plot([(12-2x)^(0.5)], x=-10..10);
Error, missing operator or `;`
this line looks right to me but i keep getting that error in maple. i have also tried:
> plot((12-2x)^(0.5), x=-10..10);
does anyone have any ideas how i can fix this?
any help would be great thanks

On Maple 11 Modern Version:
If I have two parametric curves, say y = 4t + t^4 and x = 5t - 7t^2 how can I plot an equation such as (y'') * (x') + (3x'') with ' being differential and '' being second differential.
I have tried it in numerous ways but get the following error message - "Warning, unable to evaluate the functions to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct". I have been trying to plot for t=-1..1.
Thanks

Several weeks ago I submitted a request titled "Plot This! - Elliptic Integrals", which Dr. Robert Israel responded to with the following code which successfully plots the relationship of two variables, beta and k, over the range of interest.
> with(plots); Digits := 15;
> implicitplot(2*EllipticE(sin(beta), k)-EllipticF(sin(beta), k) = tan(beta)*sqrt(1-k^2*sin(beta)^2), k = 0 .. .99, beta = 3.5 .. 5.5, view = [0 .. 1, 3.5 .. 5.5]);
However, the plot indicates that for the range of k=0..0.99, beta is approximately equal to 4.77 radians (273 degrees), whereas the paper that I am researching indicates a value of beta equal to 257 degrees 28 minutes. I have attached worksheet that includes the commands provided by Dr. Israel for information.