Maple Questions and Posts

These are Posts and Questions associated with the product, Maple

Dear all,

 

I am trying to plot in the same graph two sets of data points given by vectors. Please see the example below. Any help will be highly appreciated. Thanks!

 

question.mw

Hello,

Questions

1)  Can we compute the error  ( x(t-2*Pi) - x(t) )  without plotting  abs(  x( t-2*Pi ) - x(t) ) ?

     i.e. using norm 1, 2 or infinity  ?

 

2)  what is op( [ a, b, c] , F ),  where F is a piecewise function ?


Download example.mw

 

I want to plot and otherwise use the value of the parameter I'm minimizing w.r.t. Mimimize only provides me with the solution l]ike this:

 

ans := Minimize(dChisq);
     [-64.4156340847187, [x = HFloat(0.9455666933532977)]]

 

Help does not indicate how to get at the value of x which in this case I want to plot and might want to input to further calculations. Indded I don't now what to do with above ... other than I can extract the value of the 'chisq' at the minimum. But I can't get at the important number which is where the minimum is.

No way to get the uncertainty on x is evident either. I could do this myself but need to know the value at the minimum to do it.

 

 

It seems to be a bug here:

restart;
with(Iterator):
M := CartesianProduct([1,2],[a,b],[c,d,e], rank=3):
n:=0:  for v in M do n:=n+1: print(n,v); end do:

              1, [2   b   c]
              2, [2   b   d]
Error, (in unknown) improper op or subscript selector

# for rank=9  ==>  [list, b, e]     ??

Dear Community,

I have two measured series - time series actually, stored in Excel:

  • gas flow (ordered in ascending date order),
  • pressure measurements (unordered, more or less randomly distributed dates),

I would like to:

  • import the two series into Maple,
  • convert them to time series,
  • merge them in a way, that the unordered pressure dates are plugged into the ordered gas flow dates, so I finally get a single, ordered date sequence of ascending order.
  • pressure and gas flow rates should remain separated of course, i.e. not merged (they should appear in two separate vectors, or matrix columns, whatever)
  • if pressure dates and gas flow dates are the same, they should naturally be in the same row, i.e. belong to the same date.

No problems with the import, but I'm lost with the time series handling. I tried to figure it out from the help, but frankly the description is rather difficult, and I also haven't found appropriate examples. Is it possible to do it with Maple's time series feature at all, or something other is more practical? Files and my initial trial are attached.

tx in advance

best regards

Andras

Time_Series_Data.xlsx

TimeSeriesTest.mw

Let say I have an array

A := Array([[1], [2], [3]])
Normally if I would like to extend it I will write, eg:

Extend(A, [[4], [5]])

But because this is not 1D array Maple will rise an error. Is there a way to go over this limitation?

Dear all,

I would like to evaluate mathematical quantities involving 3F2. The function hypergeom in Maple is most probably the so called ordinary hypergeometric function commonly denoted as 2F1.


I was wondering whether 3F2 has already been implemented in Maple. Thank you.

Hello people in mapleprimes,

 

To the following expression, I want to apply applyop so that I want to change its denominator expanded ,

but I don't know how to do it.

So, I am writing now hoping someone  teach me it.

m:= 2*p/(p^2+1)^2;

 

op(m) brings the result of 2, p, 1/(p^2+1)^2,

And, op(1,m) is 2, op(2,m) is p and op(3,m) is 1/(p^2+1)^2, and

op([3,1],m) is p^2+1 and op([3,2],m) is -2.

So, the tree is `*`{2,p, 1/(p^2+1)^2}, and the tree of 1/(p^2+1)^2 is `^`{p^2+1,-2}.

And, the command expand can't play that rule on 1/{(p^2+1)^2} as its original rule is

to expand the mere numerator. And, anyway, 1/{(p^2+1)^2} is interpleted by maple as (p^2+1)^(-2),

which is not 1 devided by (p^2+1)^2, the latter of which is seen to be expanded to be p^4+2*p^2+1, but

the interpletation by maple of it is not so, and if applyop(`denom`,expand,m) works, even it is good.

But, it doesn't follow the syntax of maple. Then, can't use applyop in this case?

Best wishes.

taro

hi.

i have problem with this eq.

i need your help.

Hello,

I'm stuck with maple 2016 as it crashes after a few minutes use.

it did work for a few weeks. It appears that its java crashing,

ive been given no error code or anything. uninstalling java and reinstaling did work.

im running the proper bit version. (64) rollio

tried backrolling windows, didnt work.

tried running it as Administrator no luck, ran it on backward compatibility windows 8 and 7. 

ive run out of ideas the last option seems to be a clean windows install.

any help would be greatly appreciated.

 

the laptop in question (HP notebook 15-ba005no)

runs windows 10 (64bit)

8gigs of ram

cpu AMD E2-7110 1.8 GHz

128 GB SSD

 

gpu amd radeon r2

 

thanks in advance. 

 

dkdwarf.

 

Hello,

I've got the following problem: Sometimes when I let Maple compute an integral it gives a result which is much smaller than it should be. This happens even for rather simple integrals such as the product of a Gauss function and a 1/x-type function. Here's a minimal working example:

restart;
with(plots):
f := x -> exp(-x^2):
g := (x,a) -> 1/(1+abs(x-a)):
plot([f(x),g(x,3)],x=-3..10):
for a from 1 to 100 do
A[a] := int(f(x)*g(x,a),x=-infinity..a-1)
end do:
B:=[seq(A[a],a=1..100)]:
X:=[seq(a,a=1..100)]:
plot(X,B);

The plot it returns looks like this:

which is clearly wrong between around a=35 and a=60...

Does anyone have an idea how this can be repaired?

Hello,

I try to use the Explore function on a trigonometric expressions depending of 8 parameters. My aim is to study the influence of these parameters on the results.

However, i receive an error message and I didn't manage to troubleshoot it.

May you have a look of an extract of my code and see if you see the mistake ?

TestExplore.mw

Thanks a lot for your help.

 

 

Dear sir

 

I try the below program and it is not executing because of error and that error is " unable to match delimiters" 

Please can you varify it.

sol1 := dsolve([diff(diff(diff(f(eta),eta),eta),eta)+f(eta)*diff(diff(f(eta),eta),eta)+((2*n)/((n+1)))*(1-diff(f(eta),eta)^2) = 0, 1/(Pr) *diff(diff(theta(eta),eta),eta)+f(eta)*diff(theta(eta),eta)-((2*p)/((n+1)))diff(f(eta),eta)*theta(eta) = 0, f(0) = 0, D(f)(0) = 1+lambda*'@@'(D,2)(f)(0), D(f)(10) = 1, theta(0)=0, theta(0)=1+sigma*D(theta(0)),theta(10)=1], numeric, method = bvp);  plots[odeplot](sol1, [eta, `@@`(D,2)(f)(eta)], color = red,axes=boxed);

Dear Community,

Is there an explicit command to remove rows or columns from a DataFrame? I've only found the Append command. What's the easiest way to do it?

Tx in advance,

best regards

Andras

eq2 := -4*A[2]*cos(2*x)-16*A[4]*cos(4*x)-36*A[6]*cos(6*x)-64*A[8]*cos(8*x)+a*A[0]+cos(8*x)*a*A[8]+cos(6*x)*a*A[6]+cos(4*x)*a*A[4]+2*cos(2*x)*q*A[0]+cos(2*x)*a*A[2]+q*A[8]*cos(6*x)+q*A[8]*cos(10*x)+q*A[6]*cos(4*x)+q*A[6]*cos(8*x)+q*A[4]*cos(2*x)+q*A[4]*cos(6*x)+q*A[2]*cos(4*x)+q*A[2]

How to extract the co-fficent that do not have cos in it like

a*A[0]+q*A[2]

First 1051 1052 1053 1054 1055 1056 1057 Last Page 1053 of 2224