erik10

I have a degree in Mathematics and Physics from the Danish University Aarhus, comparable to a masters degree with thesis - majoring in Mathematics. In 1991-92 I was a visting scholar at UCLA, Los Angeles, following graduate courses in Applied Mathematics. Since 1992 I have been a teacher in a high school (gymnasium) in Denmark. Special interests: Applied mathematics, graphics and popularizing Mathematics.

MaplePrimes Activity


These are replies submitted by erik10

Hi dskoog

Thanks for listening to these complaints. I am pretty sure this behavior with empty holes in print and pdf will result in an outcry from users on not just the academic school where I am employeed, but many other places too. I had say it need to be resolved rather fast in a service update. Else, people like myself, who have recommended the use of Maple on our school, will have a hard time defending this behavior. Some people might even ask for another system. It is crucial that prints and pdf look reasonable well!

I know it is probably impossible to make things look exactly like they do on screen - since people use different screen formats, etc. It is however very important to address the following:  

1. Removing the empty holes on print/pdf.

2. Scaling images and plots by dragging in the worksheet should result in a scaling in print/pdf.

Regarding 2: As it is now, dragging an image in the worksheet does not affect the print at all! I have produced several instruction documents in Maple about Maple and converted them to pdf for my students. They contain screenshot images. If I take a print in Maple 16, some images are so small that it is impossible to read. That is OK, if I just have the choice to drag those images in the worksheet and have them bigger when printed. But it simply doesn't work!! So as it is now, I can basicly fold my Maple instructions and put them in the garbage can!    

If you can't solve those two issues, I had prefer if you go back to how it was in Maple 15! I hope though that Maplesoft can find out how to keep the more resonable looking images and plots as introduced in Maple 16 and at the same time have those two issues solved.   

I really hope this problem is resolved when I start up school again in mid-august. Thanks for listening to the users.

Regards,

Erik

I have read all your remarks on this new smartview thing with interest. I think I understand your different views on this matter. Anyway I often evaluate the different features to if they will work good for my students, not myself. Therefore I was delighted when I watched the new smartview feature on video. It really makes a difference to have plots of say 1/x plotted in a way students can use or understand without having to manipulate the ranges too much. Weak students might think something is wrong when they see the plot of 1/x in Maple 15. In Maple 16 it is much better. However I guess one have to realize that we cannot have the best of all Worlds. In a few circumstances it is better without smartview. Then the question: When should smartview be overridden? One of you suggest that just adding the x-range to the plot command should disable smartview. In that case the smartview feature cannot be applied for a lot of functions with vertical asymptotes, since you need to use an x-range different from the default one from -10 to 10. Therefore I don't like it.

I suggest the following: When the user specify the x-range, say plot(exp(x),x=-3..3), the smartview should be inwoked on the y-axis, as Dave H tell us it already does. But then the "empty holes" on the x-axis should not be removed. Only if the user also specifies the y-range, say plot(exp(x),x=-3..3,y=-1..10), then smartview should be completely disabled.

Explanation: I simply don't like Maple to override the students request of having the x-range from -3 to 3. It will confuse them I am sure, and make them uncertain. It doesn't really matter if there are some holes to the right and left. The student will know how to increase the y-range to watch more of the graph.   

I don't know if I have overlooked some cases, in which my suggestion won't work for?  

NB! Great that employeed at Maplesoft take part in these discussions!


Regards,

Erik

Hi Acer thanks a lot for referring me to the trick with the unpply command. I have seen it before, but didn't think about it in this situation.

Problem solved!

Erik

Hi Acer thanks a lot for referring me to the trick with the unpply command. I have seen it before, but didn't think about it in this situation.

Problem solved!

Erik

Nice MemTest application, PatrickT. I downloaded and tested my RAM. 400% and no errors, so I guess we can rule out the memory as a potential source of error. I have set the Tools > Options > General tab > Set "Enable RTF copy" to "Always". That way I am allowed to copy bigger sections of a document. Good suggestion.

From your and Jakubi's contributions I am beginning to think the clipboard problem can have to do with the Graphics Card in some way. Before asking on this forum I did not think of this as a possibility at all.

Maybe I should mention that I have also had other problems recently: Sometimes when copying a section of text and MathType formulas (Graphics elements) inside a Word document, only the text is copied, leaving empty holes at the places containing the original graphics elements. And yesterday another strange thing occured when using Maple. I was moving a slider in a Maple Document containing components back and forth. Suddenly the screen froze and a shaking pattern of pink pixels were displayed on the screen. The only way I could get my machine working again was to hold the start button in for 4 seconds to reboot.

Does my last details point in the direction of an issue with the Graphics Card?

Any comments are welcome!

 

Regards,

Erik   

Nice MemTest application, PatrickT. I downloaded and tested my RAM. 400% and no errors, so I guess we can rule out the memory as a potential source of error. I have set the Tools > Options > General tab > Set "Enable RTF copy" to "Always". That way I am allowed to copy bigger sections of a document. Good suggestion.

From your and Jakubi's contributions I am beginning to think the clipboard problem can have to do with the Graphics Card in some way. Before asking on this forum I did not think of this as a possibility at all.

Maybe I should mention that I have also had other problems recently: Sometimes when copying a section of text and MathType formulas (Graphics elements) inside a Word document, only the text is copied, leaving empty holes at the places containing the original graphics elements. And yesterday another strange thing occured when using Maple. I was moving a slider in a Maple Document containing components back and forth. Suddenly the screen froze and a shaking pattern of pink pixels were displayed on the screen. The only way I could get my machine working again was to hold the start button in for 4 seconds to reboot.

Does my last details point in the direction of an issue with the Graphics Card?

Any comments are welcome!

 

Regards,

Erik   

Thanks Markiyan. I actually discovered the possibility of using the Layout Palette myself. I am not quite satisfied with it, however. Unfortunately the symbol ^ is stretched to look like part of a circle.

Why doesn't Maple deliver a set of symbols comparable to the set delivered by a text/math typesetting program like LATEX? Maybe they don't want to add symbols, which do not have any computational meaning??

Erik

Thanks Markiyan. I actually discovered the possibility of using the Layout Palette myself. I am not quite satisfied with it, however. Unfortunately the symbol ^ is stretched to look like part of a circle.

Why doesn't Maple deliver a set of symbols comparable to the set delivered by a text/math typesetting program like LATEX? Maybe they don't want to add symbols, which do not have any computational meaning??

Erik

Hi Alejandro

You saved me!! Your suggestion made me look for the installation log file in the C:\Programs\Maple 15 folder. This log file revealed all of the installed files, as you mentioned. I did not touch the math fonts ESSTIX... and the MaplePi font, but I had deleted the Courant, Helonia and Thames font groups. Luckily I was able to recover them from the garbage can :) So along with all eight Lucida fonts, all font are now present. Thanks a lot!

Erik

Hi Alejandro

You saved me!! Your suggestion made me look for the installation log file in the C:\Programs\Maple 15 folder. This log file revealed all of the installed files, as you mentioned. I did not touch the math fonts ESSTIX... and the MaplePi font, but I had deleted the Courant, Helonia and Thames font groups. Luckily I was able to recover them from the garbage can :) So along with all eight Lucida fonts, all font are now present. Thanks a lot!

Erik

@acer I agree with you. Those numerical procedures need a limited interval to work inside. Maple choses the interval from -10 to 10 for the Roots command by default. It does not mean it is the most appropriate - it just need to choose one! Unfortunately it is impossible to tell which interval is the best in a specific situation, without doing an in-depth analysis of the function involved. We have just experienced above that choosing a bigger interval might result in fewer zeros found. Quite possible it might even happen that reducing the interval (still containing the true zeros) will result in fewer zeros found. All this just emphasize the troubles when dealing with equations - even with one variable only! Let someone describe a procedure to find all zeros of any (continous) function in a given limited interval. Then probably one will be able to find a function sufficiently weird, which will fail. I won't be the one to find it, though ;)

Maybe the methods will work better (but not perfect) in average for equations associated with a differentiable function. I studied some Numerical Analysis at UCLA, Los Angeles, but it is 20 years ago ...

You are right that it could be valuable to point out the numerical problems - using an example - to even High School students, so they will realize they cannot always just press a button and expect to get all solutions of any equation in a second! It will give some insight into the subject.

Regards,

Erik

@acer I agree with you. Those numerical procedures need a limited interval to work inside. Maple choses the interval from -10 to 10 for the Roots command by default. It does not mean it is the most appropriate - it just need to choose one! Unfortunately it is impossible to tell which interval is the best in a specific situation, without doing an in-depth analysis of the function involved. We have just experienced above that choosing a bigger interval might result in fewer zeros found. Quite possible it might even happen that reducing the interval (still containing the true zeros) will result in fewer zeros found. All this just emphasize the troubles when dealing with equations - even with one variable only! Let someone describe a procedure to find all zeros of any (continous) function in a given limited interval. Then probably one will be able to find a function sufficiently weird, which will fail. I won't be the one to find it, though ;)

Maybe the methods will work better (but not perfect) in average for equations associated with a differentiable function. I studied some Numerical Analysis at UCLA, Los Angeles, but it is 20 years ago ...

You are right that it could be valuable to point out the numerical problems - using an example - to even High School students, so they will realize they cannot always just press a button and expect to get all solutions of any equation in a second! It will give some insight into the subject.

Regards,

Erik

@acer Thanks for your further investigations. The maxdistance option in the NextZero command is interesting. And thanks for the revised procedure. Maybe your procedure will even do a better job than the Roots command implemented by Maple itself? Execution time can be long, though, if a large interval is chosen.

I am completely aware that my suggestion to visually inspect plots isn't foolproof. Some zeros might still be overlooked. Unfortunately a mechanical way to find all zeros for any kind of function probably doesn't exist.Only an analytical examination of the function at hand will be able to rule out the presence of more zeros. For High School students, who don't have this analytical capacity, it might however be a good guide to look at plots in order to hopefully find all zeros.  

NB! I liked your description on how you found improvements in the code during a long drive. Such long periods of boredom can sometimes help the mental activity :)

Regards,

Erik

@acer Thanks for your further investigations. The maxdistance option in the NextZero command is interesting. And thanks for the revised procedure. Maybe your procedure will even do a better job than the Roots command implemented by Maple itself? Execution time can be long, though, if a large interval is chosen.

I am completely aware that my suggestion to visually inspect plots isn't foolproof. Some zeros might still be overlooked. Unfortunately a mechanical way to find all zeros for any kind of function probably doesn't exist.Only an analytical examination of the function at hand will be able to rule out the presence of more zeros. For High School students, who don't have this analytical capacity, it might however be a good guide to look at plots in order to hopefully find all zeros.  

NB! I liked your description on how you found improvements in the code during a long drive. Such long periods of boredom can sometimes help the mental activity :)

Regards,

Erik

Hi Christopher

The help pages say that if no range is provided with the numeric option, the range -10 to 10 is chosen by default, so we were just plain lucky there :)

But you are right that it is odd that Maple find less solutions in a bigger interval. I guess Maple choses some fixed number of points to apply the fsolve command to keep the amount of computation limited, in order to deliver the result within a reasonable timeframe. A bigger interval then means larger distance between the points, which can easily have an influence on the number of roots found - the output of the fsolve command depend on the initial value ... This is just a guess. I don't know if the Roots command is implemented in this way. It could explain the mystery at least.

Erik    

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