The following integral
f := u-> int(-1/(x*sqrt(-1+u^2*(x+1)^2*x^2)), x = (1/2)*(-u-sqrt(u^2-4*u))/u .. (1/2)*(-u+sqrt(u^2-4*u))/u);
arised in an applied research. I was asked about its properties:
plot on RealRange(4,infinity), limit(f(u),u=4,right), limit(f(u),u=infinity).
Unfortunately, I lost a file. As far as I remember it, I have had a problem with
the last-named one only:

limit(f(u), u = infinity);

MultiSeries:-limit(f(u), u = infinity);

asympt(f(u), u, 2);

Error, (in asympt) unable to compute series

Hope my colleagues will make progress with it. The assumed value is Pi/2.

Of course, with Maple. This object is described in Wiki.
Its plot looks like

Also the 2d Gaussian free field is of great interest. As far as I understand it, a one-dimensional Gaussian random field is formed by the
Finance[GaussMarkovProcess] command of Maple.

PS. The googling brings, in particular, http://mathematica.stackexchange.com/questions/4829/efficiently-generating-n-d-gaussian-random-fields.

I'm trying to use the stats graph feature in Maple 17, but I do not know how to change the x-axis in a bar graph. The values that are default are 1, 2, 3,... but I would like to have words instead. Any idea how to do this?

I seem to have an error or maybe two when I use dsolve and I've traced it back to my defining functions.  I know I'm probably not defining something the right way.

a:=m*(diff(x(t), t,t))+beta*(diff(x(t), t))+m*9.8*(f'(x)/(1+(f'(x)^2)))

f:=x->sin(x)

de:=a=0

m:=0.01;beta:=0.01;

                           m := 0.01
                          beta := 0.01
with(Physics):
ic:=x(0)=0,D(x)(0)=.5;

sol:=dsolve({de,ic},x(t),numeric)

                        Error, (in dsolve/numeric) x(t) and x cannot both appear in the given ODE

 

differential_test.mw

hi every one..

how i solve numerically  couple equations which attached below .in solve this equation we must  starting from a very small value of V(voltage) with initial guesses for x1 and x3

near zero and using find root method.it is noted that  the solution at this voltage step are used as initial guesses

for the next voltage step, and the process is repeated..

thanks

2DOF.mw

My 5 year old laptop executes some commands very slowly e.g. plottools(rotate) around a line which is not a Cartesian axis. I intend to buy a new desktop. Which off-the-shelf desktops provide the fastest processing of Maple commands which do not include large data sets? Which provide the best price/performance?

Hello

I have this task which says:

Find the equation of the tangent for the function: f(x)= -ln x + e^x P(2,f(2)).

So, I first defined the function in Maple: f(x):=-ln(x)+(e)^(x)

then I wrote the equation of the line which is: y = f(2)*(x-2)+f(2)

BUT it does not work! Help me plzzzz

f(x):=-ln(x)+(e)^(x)

The following code works fine:

restart;
with(LinearAlgebra): with(MTM): with(StringTools): MultivariateNormalSample := proc (Sigma, V, N) local d; d := LinearAlgebra:-Dimension(V); LinearAlgebra:-LUDecomposition(Matrix(Sigma, datatype = float[8]), 'method' = 'Cholesky') . ArrayTools:-Alias(Statistics:-Sample(Normal(0, 1), d*N), [d, N])+ArrayTools:-Replicate(Vector[column](V, datatype = float[8]), 1, N) end proc: S := MultivariateNormalSample(`<,>`(`<|>`(1, 2), `<|>`(2, 5)), `<,>`(2, 3), 100):
W := ~int8(~round(S)):
K := convert(W, string):
K := Drop(K, 17):
K := Select(IsDigit, K):
M := seq(PadRight(K[i], 2), i = 1 .. Length(K)):
Z := M[1]:
for i from 2 to Length(K) do Z := cat(Z, M[i]); if `mod`(i, 2) = 0 then Z := cat(Z, "\n") end if end do:
Z;

but if I make a proc out of it then it breaks down on the line:

 W := ~int8(~round(S)):

There seems to be an issue with the elementwise tilde operator.

restart;
Generate:=proc()
local MultivariateNormalSample,S,W,K,M,Z,i;
with(LinearAlgebra): with(MTM): with(StringTools):
MultivariateNormalSample := proc (Sigma, V, N) local d; d := LinearAlgebra:-Dimension(V); LinearAlgebra:-LUDecomposition(Matrix(Sigma, datatype = float[8]), 'method' = 'Cholesky') . ArrayTools:-Alias(Statistics:-Sample(Normal(0, 1), d*N), [d, N])+ArrayTools:-Replicate(Vector[column](V, datatype = float[8]), 1, N) end proc: S := MultivariateNormalSample(`<,>`(`<|>`(1, 2), `<|>`(2, 5)), `<,>`(2, 3), 100):
W := ~int8(~round(S)):
K := convert(W, string):
K := Drop(K, 17):
K := Select(IsDigit, K):
M := seq(PadRight(K[i], 2), i = 1 .. Length(K)):
Z := M[1]:
for i from 2 to Length(K) do Z := cat(Z, M[i]); if `mod`(i, 2) = 0 then Z := cat(Z, "\n") end if end do:
return Z:
end proc;Generate();

I seem to have missed something. Any ideas?

Harry

hi.please see attached file and explain how i remove error

thanks alot

error3.mw

Maple 2015, Windows 7 Pro

Notice the printout of the following example.  The true/false Maple evaluations are incorrect because I do not know what TYPE command to put in the printf expression.  However, the format of the printout is what I want.

restart;
r:= [17=15,16<17,17>18]:
printf("%{}9a\n\n%{}9a\n\n", <r>,<type~(r,anything)>)



  17 = 15   16 < 17   18 < 17

     true      true      true

In this second example the Maple evaluations of the statements are correct, but I want the print format to flow accross the page rather than down the page.

restart;
for r in [17 = 15, 16 < 17,18 < 17]
do
printf("%{}9a\n\n%{}9a\n\n",<r>,<evalb(r)>)
end do;
  17 = 15

    false

  16 < 17

     true

  18 < 17

    false

Could someone show me how to modify the second example so that the printout will flow across the screen rather than down the screen.  Thanks in advance, Les  PS I'd like to keep the loop if possible.

I have y"+y=sinx

If I want to substitute y=sinx, how should I do it?

I tried subs(y=sin(x),f(y))(ofc after defining f:=y as above).

The most troubling thing is that it does not automatically apply double derivative.

I have the following code of a plot:

plot(
[
add(BS(bb[4], t, i, 3)*bb[1](i+1), i = 0..n),
add(BS(bb[4], t, i, 3)*bb[2](i+1), i = 0..n),
t = 0..1
],
color=red, axes=normal, scaling=constrained, numpoints=100, thickness=2
):

and I get the following error:

Error, (in BS) cannot determine if this expression is true or false: 0 <= t and t < .54901960784313725490196078431373

The problem is that, in the definition of BS, there are some conditions that depend on the variable t. It seems that Maple does not use a specific value of t when executing BS. My solution is to plot specific points, i.e., 

plot(
[
seq([add(BS(bb[4], h/5000, i, 3)*bb[1](i+1), i = 0..n),
add(BS(bb[4], h/5000, i, 3)*bb[2](i+1), i = 0..n)], h=0..5000)
],
color=red, axes=normal, scaling=constrained, numpoints=100, thickness=2
):

Can this be done in a more elegant way?

Hello maple experts,

please is there any other way of solving this problem Wht.mw

Some complained that the graphs do not satisfy the boundary conditions smoothly.

Thanks.

How can I display in Maple T.A. the content of a matrix as pure text?

Thus instead of

matrix([[1, 2], [3, 4]])

1 2

3 4

Is there a solution without using Mathml and hopefully without using StringTools?

And can I assign the rectangular text display to a variable (including line feeds)?

Harry