Georgios, I'm glad to learn that still works in Maple 11. Many thanks, J. Tarr

Georgios, I'm glad to learn that still works in Maple 11. Many thanks, J. Tarr

Try this: restart; f := 25*sqrt(2)*(int(sin(x)/sqrt(x), x = 0 .. x))+50*cos(x)-52.065; plot(f,x=0..6); evalf(eval(f,x=1/2)); Hope this helps, J. Tarr

Switching between 1D and 2D in Maple on XP works as Joe says. Switching between document mode and worksheet mode is described in the Quick Reference Card. Insert a prompt [> using the ToolBar, or Ctrl+J (or Ctrl+K if you want the worksheet mode before the document block). Going the other way, Format>Create Document Block is the official way, but Ctrl+J (or Ctrl+K), then Ctrl+T and then F5 seems to work. Hope this helps, J. Tarr

Yes, all XP users suffer from Maple's flashing screens. Something to do with Maple's use of Java. The doc tells me that too much coffee affects us humans this way, so I guess that Maple is high on Java. One of the GUI gurus will be able to give you the technical explanation. J. Tarr

Since posting the link to FAQs, someone has tidied the FAQs page and broken the link. If you visit the new FAQs and search under firewall you'll get 4 hits. The second is the most helpful. Hope this works for you, J. Tarr

Maybe it's a firewall problem. Please see Maple

Please see ?Optimization,Options under initialpoint. If you can make some good estimates for a[1]..c[12] and use these as the initialpoint that will find the nearest minimum, which could be the global minimum that you want. Without any knowledge of your problem, I tried this list of pure guesses: ini := [seq(a[i]=1,i=1..12),seq(b[i]=1,i=1..12),seq(c[i]=2,i=1..12)]; and obtained several different minima, the least being 3.7917. Hope this helps, J. Tarr

It would make life easier for those who could help you if you uploaded your worksheet, instead of a mass of text. Regards, J. Tarr

I wrote a procedure you might be able to adapt. Hope this helps, J. Tarr

I wrote a procedure you might be able to adapt. Hope this helps, J. Tarr

I believe that the "disks" option is available only in StudentCalculus1 VolumeofRevolutionTutor. That should plot the disks in the worksheet on closing the Tutor window. Hope this helps, J. Tarr

Why do you expect to obtain an identity matrix? J. Tarr

Jinny, Your contribution doesn't really belong to this thread. Next time, please start a new thread in similar circumstances. If you do this at the end of your worksheet: soln2 := dsolve({sys, initcon}, {nCH4(z), nH2O(z), nCO(z), nH2(z), nCO2(z), T(z)}, type = numeric,output=listprocedure); Maple will produce a list of procedures giving the solutions for each of the variables as a function of z. Then follow the example 2.5 to 2.9 at ?dsolve/numeric/IVP. Inserting any non-zero value of z into any of these procedures, produces an error message "cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up". That should point you toward the terms in your worksheet that may be causing the problem - denominators that can become zero, roots that may become complex, etc, depending on the value of z. As a first move, you should tidy your worksheet - it contains many duplicated and skipped (#) terms. You may also need to build your model again, starting with something very simple and adding complexity step by step and only when the previous step works OK. Good luck, J. Tarr

Jinny, Your contribution doesn't really belong to this thread. Next time, please start a new thread in similar circumstances. If you do this at the end of your worksheet: soln2 := dsolve({sys, initcon}, {nCH4(z), nH2O(z), nCO(z), nH2(z), nCO2(z), T(z)}, type = numeric,output=listprocedure); Maple will produce a list of procedures giving the solutions for each of the variables as a function of z. Then follow the example 2.5 to 2.9 at ?dsolve/numeric/IVP. Inserting any non-zero value of z into any of these procedures, produces an error message "cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up". That should point you toward the terms in your worksheet that may be causing the problem - denominators that can become zero, roots that may become complex, etc, depending on the value of z. As a first move, you should tidy your worksheet - it contains many duplicated and skipped (#) terms. You may also need to build your model again, starting with something very simple and adding complexity step by step and only when the previous step works OK. Good luck, J. Tarr