@corregumucio Ok. It can still be as flexible, without actual assignment.

> restart:

> eqxy1:=x+2*y=4:
> eqxy2:=x^2+y^2=16:

> xysol:=solve({eqxy1,eqxy2},Explicit);
                               /    -12      16\ 
              {x = 4, y = 0}, { x = ---, y = -- }
                               \     5       5 / 

> x=eval(x,xysol[1]);
                             x = 4

> eqrsxy1:=s*x+y^2*r=11;
                               2       
                        s x + y  r = 11

> eval( eqrsxy1, [x=eval(x,xysol[1])] );
                               2       
                        4 s + y  r = 11

And I guess I didn't give this shorter one before,

> restart:
> with(LinearAlgebra):
> with(Student):

> MatrixInverse(Matrix([[4]]));
Error, MatrixInverse is not a command in the LinearAlgebra package

acer

And I guess I didn't give this shorter one before,

> restart:
> with(LinearAlgebra):
> with(Student):

> MatrixInverse(Matrix([[4]]));
Error, MatrixInverse is not a command in the LinearAlgebra package

acer

Ahh. It looks like it all worked in Maple 9, and that my 2nd and 3rd examples changed behaviour starting with Maple 9.5.

acer

Ahh. It looks like it all worked in Maple 9, and that my 2nd and 3rd examples changed behaviour starting with Maple 9.5.

acer

The Standard GUI no longer seems able to display the intermediary objects with attributes on them. (That fact is hidden, if one immediately sorts them and returns the underlying attributes instead, in just a single command.) This seems to have changed between Maple 11 and 12.

acer

See here for a look at question 2.

acer

@afeddersen ExpectedValue computes the integral of x*f(x) for density function f, where the `x` weight is unstated (ie. implicit) but automatically inserted. So if you want to replace that implicit weight x by U(x), while using a new random variable to supply directly to ExpectedValue, then its PDF must be weighted by U(x)/x. It'd look like this, then,

with(Statistics):
assume(mu::real,sigma>0);
X:=RandomVariable(Normal(mu,sigma)):
Y:=RandomVariable(Distribution(PDF=subs(f=unapply(PDF(X,T),T),t->(1-exp(-phi*t))/t*f(t)))):
EY:=ExpectedValue(Y);

and it does indeed get the same result.

@afeddersen ExpectedValue computes the integral of x*f(x) for density function f, where the `x` weight is unstated (ie. implicit) but automatically inserted. So if you want to replace that implicit weight x by U(x), while using a new random variable to supply directly to ExpectedValue, then its PDF must be weighted by U(x)/x. It'd look like this, then,

with(Statistics):
assume(mu::real,sigma>0);
X:=RandomVariable(Normal(mu,sigma)):
Y:=RandomVariable(Distribution(PDF=subs(f=unapply(PDF(X,T),T),t->(1-exp(-phi*t))/t*f(t)))):
EY:=ExpectedValue(Y);

and it does indeed get the same result.

I enjoyed the content of this post, and give it the thumbs up vote.

But I have a few comments on the Mapleprimes technical side of things.

These technical blogs would look much better if the baseline for 2D math inlined into regular text paragraphs was fixed. Currently, it typesets much too high, and as a consequence the end result looks amateurish (no matter how great the content might be).

In Table 2, named "Matrix Action: 2D" there is a Component which currently contains just the name A. Is it instead supposed to show the printed entries of some Matrix A?

When viewed in firefox, the buttons in Tables (presumably corresponding to Component Buttons in an original worksheet) seem to act like html buttons. They can be pressed. But doing so just causes the worksheet to redisplay. So it gives a confusing impression, of potential interaction.

acer

See here.

acer

See the help-page ?ln for what Maple is taking as the principal branch.

acer

See the help-page ?ln for what Maple is taking as the principal branch.

acer

I thought that it would work because there are buttons for such markup on the editing bar of the post-editor. That's how I added in a centered h2 header, by using the editing bar's buttons. It seems strange to have several layout buttons in the site's editor if they add html markup which only ever causes the affected text to be stripped out.

That list of allowed tags is useful, thanks! Maybe it could be added to the MaplePrimes Help page.

acer

@Alejandro Jakubi Ok, sure, although I was thinking about where CompileTools:-Copy was forcibly copying the shared object file. One might not want to have the location of saved Compile'd procs's shared objects be the same as for all other temporary ones (or of anything else that might use that location). Thanks for mentioning it, though, as it may be useful in ways not yet considered.