Alex Smith

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20 years, 267 days

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These are replies submitted by Alex Smith

Jacques, What other computational approaches are there to definite integration other than the Fundamental Theorem? I suppose identify(evalf(Int(f(x),x=a..b)); is one possibility when the result is a number. The "identify" command is a scary thing, but after this recent experience, I almost feel more comfortable with this than with int(f(x),x=a..b)); You would think that the int routine would do a reality check to see if the result given by FTC via the Risch algorithm makes sense by comparing with evalf(Int...), but I guess it does not.
Thanks for isolating the problem. Now I see that even for a simpler situation like int(cos(t)*sqrt(cos(2*t)),t=-Pi/4..Pi/4) Maple uses a discontinuous antiderivative, and so gets the definite integral wrong. Mathematica, on the other hand, returns the continuous antiderivative (1/4)*arcsin(sqrt(2)*sin(t))*sqrt(2)+(1/2)*sin(t)*sqrt(cos(2*t)) and gets the definite integral correct. This is kind of depressing.
What I thought was interesting about John Fredsted's ToTree and FromTree was this: Many times over the last few years I would want to get the tree for a Maple expression. When you enter "tree" into the Maple help text search, nothing useful comes. Or if it does, it does not standout. So "help" was of no help. Thus I would randomly poke around with "op" to randomly figure out tree. This was a rather pitiful enterprise. After all this, now I know how to get the tree effectively. Axel offers a beer if you are in Munich. Alex offers a beer if you are ever in Wisconsin. Wisconsin is noted for its beer, and some of it is good. I don't know if we can compete with Munich, but Wisconsin beer does has its own niche.
Instead of the double do loop, you could simply generate A as follows: restart; deg2rad := (1/180)*Pi; A:=Matrix(45, 10, (i,j) -> evalf(EllipticF(sin(i*deg2rad), sin(5*(j-1)*deg2rad)))); So the general idea is that B:=Matrix(n,m, (i,j)->f(i,j)) generates an n by m matrix whose (i,j) entry is f(i,j).
Instead of the double do loop, you could simply generate A as follows: restart; deg2rad := (1/180)*Pi; A:=Matrix(45, 10, (i,j) -> evalf(EllipticF(sin(i*deg2rad), sin(5*(j-1)*deg2rad)))); So the general idea is that B:=Matrix(n,m, (i,j)->f(i,j)) generates an n by m matrix whose (i,j) entry is f(i,j).
The construction L[ ] instead op(L) is new to me and really cool. I do not understand the "logic" behind it, but I will adopt it!
The construction L[ ] instead op(L) is new to me and really cool. I do not understand the "logic" behind it, but I will adopt it!
The most important functionality that SciWP has that Maple does not have is LaTeX.
The most important functionality that SciWP has that Maple does not have is LaTeX.
>launch("C:/Program Files/QuickTime/QuickTimePlayer.exe"); worked perfectly fine for me in classic Maple11. Why am I not shocked to find that it does not work in the "standard" interface? The "standard" interface is going to be the death of Maple. Please...do not stop development of the classic interface!!!
>launch("C:/Program Files/QuickTime/QuickTimePlayer.exe"); worked perfectly fine for me in classic Maple11. Why am I not shocked to find that it does not work in the "standard" interface? The "standard" interface is going to be the death of Maple. Please...do not stop development of the classic interface!!!
If you would post the text so we can copy paste from your post to our Maple worksheets, or post the worksheet, then we would find it easier to help you. eq1:=1/2*(A/lots of stuff)=M1; etc. As it stands, we have to carefully input your equations.
Yes, I can reproduce you problem. If you type > for a from 1 to 4 do [tab]print (a): end do: (new lines created with "Shift-Enter") you can reach the end of the line with the "end" key. Then if you copy and paste to new prompt, the "end" key will not push you to the end of the tabbed line. It sees to me like "shift-enter" has something to do with the anomaly. If you start with >for a from 1 to 4 do > [tab] print (a): >end do: (so the new lines above are created with "Return" instead of "Shift-Enter"), then the copy/paste bug does not surface-you can get to the end of the tabbed line with the "end" key.
I had not noticed the tab-toggle icon, but then I never look at icons.
I bet this sort of thing depends on whether you are using Windows, unix, Mac, etc. With Windows, all "tab" does is move me down to the next prompt, if there is one. It does not create blank space. If I copy from a text editor where tab gives blank space, the blank space is converted to four single spaces.
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