Doug Meade



Douglas B. Meade <><
Math, USC, Columbia, SC 29208 E-mail:
Phone: (803) 777-6183 URL:

MaplePrimes Activity

These are Posts that have been published by Doug Meade

My previous blog entry was a real success. Even though my original idea about multi-part MIME has not gotten anywhere, I do now have a concise way to package a maplet with supplemental files in a single package that can be downloaded via the WWW and automatically extracted and executed. Most of the ideas were presented by acer. acer first suggested that I look at the interactive interface to the InstallerBuilder. The idea here was to embed the maplet in a worksheet saved in a help database (hdb). This did work, but was not suitable for actual use due to the overhead of the installer. In the attempt to reduce this overhead, acer then supplied some code that used march and LibraryTools. To test the product of this interaction, download the file at the URL
Increasingly, I see the need to distribute a Maple worksheet with some auxiliary files. These extra files typically contain additional Maple code. These extra files could be a command file, a Maple libray archive (mla) or an image (for use in a maplet, say). I can create my own ZIP archive to e-mail, but I would like to be able to post some of these resources on my website in a format that they can be automatically executed when downloaded. I understand that there are some potential security issues here, but I still like to see if there cannot be some support for this functionality. What I have in mind is something very similar to the way attachments are handled in e-mail with multi-part MIME.
In my work developing Maplets for Calculus, there are many instances when I want to determine that a function is monotone (decreasing or increasing or non-decreasing or non-increasing) on an interval. If I can do one of these, I can do them all. So, let's focus on decreasing. I have no problem assuming f is continuous and differentiable on the interval. The interval could be unbounded, and I am not terribly concerned about endpoints (at least now). Given a function f, how would you use Maple to determine that f is decreasing on an interval (possibly unbounded)?
Can anyone explain why Maple has so much trouble deciding if sqrt(2^x+x^4) is continuous for k>=1?
f := 2^x+x^4;
                                      x    4
                               f :=  2  + x 
iscont( f, x=1..infinity );
iscont( sqrt(f), x=1..infinity );
iscont( sqrt(f), x=1..100 );
solve( f>0, x );
Accoring to the online help for solve,inequal, the last result means Maple understands that f>0 for all real values of x. So, given all of this, what is the problem deciding that sqrt(f) is continuous for x>=1? OR, is this a bug?
I have been unable to send a MaplePrimes post by e-mail. I click the e-mail link, enter an e-mail address (my own, for testing), confirm that there is a link to be sent, enter something in the message body, and press Send Message. A message arrives in my inbox, but it does not contain the post I was trying to send. Here is the text version of the body of the e-mail message I received from MaplePrimes: I have confirmed that this is repeatable (at least twice in the past day).
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