John May

Dr. John May

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17 years, 14 days
Maplesoft
Pasadena, California, United States

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I have been a part of the Mathematical Software Group at Maplesoft since 2007. I have a Ph.D in Mathematics from North Carolina State University as well as Masters and Bachelors degrees from the University of Oregon. I have been working on research in computational mathematics since 1997. I currently work on symbolic solvers and visualization as well as other subsystems of Maple.

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These are replies submitted by John May

@pvrbik There is noting particularly more intuitive about using an exprseq or list instead of an Array or Table.

WeatherHistory := Array(1..50); # or table();

for i from 1 to 50 do    
    NextWeather := TransitionFrom( TodaysWeather );    
    WeatherHistory[i] := NextWeather;   
    TodaysWeather := NextWeather;
end do:

cat(entries(WeatherHistory, 'nolist'));

 

This is, arguably, even easier to read and has the bonus of not teaching students very bad habits in Maple.

@pvrbik There is noting particularly more intuitive about using an exprseq or list instead of an Array or Table.

WeatherHistory := Array(1..50); # or table();

for i from 1 to 50 do    
    NextWeather := TransitionFrom( TodaysWeather );    
    WeatherHistory[i] := NextWeather;   
    TodaysWeather := NextWeather;
end do:

cat(entries(WeatherHistory, 'nolist'));

 

This is, arguably, even easier to read and has the bonus of not teaching students very bad habits in Maple.

@PatrickT Maybe in the UK, but things don't look good for "Jamie" in the US:

@Christopher2222 You can try highlighting the code in question and selecting the "preformatted" style or hit the "html" button to manually add <pre> </pre> tags around the code.  Those should be equivalent and should preserve the formatting.

Shouldn't this be a question and not a post?

John

It seems the images in this post were eaten in the upgrade.  It showed up as recently updated since I was trying, without luck, to replace the images.

John

I think people might avoid doing something like this due to worries about the limited life of flash memory (1-5 million writes).  Though, I have also read aritcles that suggest that if you use "write leveling" to spread writes across the whole SSD then the usable life, at maximum utilization, is on the order of several decades.

John

@Alec Mihailovs That is indeed the theory up with which we came.

Interestingly, even though the Bionic woman was spelled Jaime Sommers there was primarily a giant spike in female newborns named "Jamie" (previously, primarily a nick-name for "James").  Of course, the then less popular, "Jaime" saw a, relatively, much larger spike:

And of course, the recent tab:

http://www.mapleprimes.com/recent/unread

seems pretty close to the "tracker" view on the old Primes.

 

John

The problem seems to come from a quirk in the MeijerG method integrator.  You can work around it by explicitly asking for the FToC method in Maple 13+.

int(BesselK(1,t)*t^2, t=0..x, method=FTOC);

int(BesselK(1,t)*t^2, t=0..x, method=FTOC)

plot(2-x^2*BesselK(2,x), x=0..1)

John

Explict forms are often not very readable.  That is one of the reasons the RootOf notation is used.

John

Explict forms are often not very readable.  That is one of the reasons the RootOf notation is used.

John

Currently, a large number of functions in the Maple library use solve and expect it to not respect assumptions on the independant variables and in fact break if solve is made to do so.  For that reason, the UseAssumptions option was given the default of "false" when we introduced it in Maple 13.  In a future release, after there is time to modify how all the other code calls solve, I expect that the default will be changed to true.

John May
Math Software
Maplesoft

Currently, a large number of functions in the Maple library use solve and expect it to not respect assumptions on the independant variables and in fact break if solve is made to do so.  For that reason, the UseAssumptions option was given the default of "false" when we introduced it in Maple 13.  In a future release, after there is time to modify how all the other code calls solve, I expect that the default will be changed to true.

John May
Math Software
Maplesoft

 Which is fine unless you want your .mapleinit file to work in older versions of maple where IsWorksheetInterface() returns unevaluated.

John

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