Nicole Sharp

Miss Nicole Sharp

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1 years, 284 days
Frostburg State University (FSU)
Kappa Mu Epsilon Alumna
Cumberland, Maryland, United States

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Nicole Sharp of Frostburg State University, Maryland, United States of America (USA). https://www.nicolesharp.net/

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These are questions asked by Nicole Sharp

How do I stop truncation in Maple 2023?  Everything was working fine yesterday but today all of a sudden all assignments are truncated to only 10 digits.

If:

with(Units) :

a_Terra := 149598023.*Unit(km) :
A_Luna := 0.136 :
L_Sol := 3.75E28*Unit(lm) :
S_sphere := r -> 4*Pi*r^2 :

J_Luna := A_Luna*L_Sol/S_sphere(a_Terra) :

Then:

"" gives ""

but

"" gives ""

"" without "evalf" also provides a truncated number instead of showing the "Pi" for an exact value.  So something is wrong in the assignment settings.

Somehow the settings must have changed for how assignments are stored. The answer is irrational with a factor of "1/Pi" and so should not be truncated for calculations.  "a_Terra" is assigned with 9 significant digits ("" km) which I am wondering if maybe why "evalf" is truncating to 10 digits (though it should round and not truncate in that case) but it wasn't doing this before.

"Tools --> Options --> Precision" hasn't changed is set globally to round screen display to 32 decimal places and to round calculation to 64 significant digits.

Is there a way to reassign the arcsecant function "arcsec()" as "asec()" so that "arcsec" can be assigned to the arcsecond unit "Unit(arcsec)"?

Ideally, I would like all of the inverse trigonometric functions to use the shorter notation "asec()" instead of "arcsec()".  I usually do this as aliases, i.e. "alias(asin = arcsin) : alias(asec = arcsec) :" but this won't allow reusing "arcsec" for a unit instead.

Example error for Maple 2023:

alias(asec = arcsec) :
AddUnit(astronomical_unit, context = astronomy, default = true, prefix = SI, conversion = 149597870700*m) : # https://en.wikipedia.org/wiki/astronomical_unit
AddUnit(second, context = angle, spelling = arcsecond, plural = arcseconds, symbol = arcsec, prefix = SI_negative) :

AddUnit(parsec, context = astronomy, default = true, prefix = SI, conversion = AU/tan(arcsec)) ; # https://en.wikipedia.org/wiki/Parsec#Calculating_the_value_of_a_parsec

"Pi/648000" has to be used instead of "arcsec" here when defining the parsec since "arcsec" is already reserved for the arcsecant function, even with "alias(asec = arcsec) ;".

Correction: it looks like the parsec was redefined by the IAU in 2012 as exactly "648000*AU/Pi" without any tangents (or sines) in the definition (so the angle subtended by 1 AU at 1 PC is actually 0.999999999992" not 1").  Both "astronomical_unit" and "parsec" have the wrong values in Maple 2023 which need to be corrected manually.  But the conflict between arcseconds and arcsecants remains the same.

https://iau.org/static/resolutions/IAU2015_English.pdf

https://iopscience.iop.org/article/10.3847/0004-6256/152/2/41

I just saw that Maple 2024 no longer supports importing Quandl data.

If this is a feature that I will like to use, it is possible to keep both Maple 2023 and Maple 2024 installed at the same time on Microsoft Windows 11 without conflicts?  Or should I just not upgrade to Maple 2024?  I currently have a perpetual license for Maple 2023 and am on the 15-day trial for Maple 2024.

I just installed the 15-day trial for the new Maple 2024.  It looks like Maple 2024 has the same problem as Maple 2023 in that it will not maintain a connection to MapleCloud.  I can sign in to MapleCloud no problem but as soon as I close the window, it forgets my password and I have to log back in each time I want to access MapleCloud.  Is there a way for Maple 2023 or Maple 2024 to remember my Maplesoft password so I do not have to log back in every time I want to access MapleCloud?

evalf(Pi*int(2*299792458^2*662607015*10^(-8)*10^(-34)/((exp(299792458*662607015*10^(-8)*10^(-34)/(1380649*10^(-6)*10^(-23)*lambda*5772.0)) - 1)*lambda^5), lambda = 0 .. infinity));

returns a complex number for the Solar radiant exitance in watts per square meter with an effective blackbody temperature of "5772.0" kelvins.

Replacing "5772.0" with an exact "5772" gives the correct answer though.  The nominal Solar temperature is defined as exactly 5772 kelvins whereas the physical Solar effective temperature is 5772.0 K (+/-) 0.8 K.

Is there a way to get Maple 2023 to avoid outputting these types of errors when using nonexact quantities?

I tried replacing "5772.0" with "5772.00000000001" and "5771.9999999999" and the error is not duplicated for those kelvin temperatures.

Interestingly, this error does not occur on Maple for Excel, only within the Maple desktop client....

https://scienceworld.wolfram.com/physics/Stefan-BoltzmannLaw.html

https://iopscience.iop.org/article/10.3847/0004-6256/152/2/41/

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