Christopher2222

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There is a problem with mapleprimes favorites. 

Looking at my list of favorites it cites I have 6 pages, however when I get to page 3 it shows a list of only six items and no more page listings after clicking the back button and going again to page 3 even less appear.  I was looking for specific questions and posts I have favorited which seem to be abscent from the listing. 

Can mapleprimes administrators please address the problem?

Was just pondering this idea and posted this in the post topic for discussion. 

Each Maple finished version of Maple may still have certain bugs that will not be updated for that version, so I am suggesting (I think anyone could implement it) that if there is a workaround, one could wrap it up in something I would call a patch package updateable by us users we could update here on mapleprimes.  It would be good for people who haven't upgraded or can't upgrade due to costs etc...

For example, there was recent issue with pdsolve that was fixed quite quickly in the seperate updateable Physics package.  Things could be done similarily that might work with other workarounds using this patch package idea. 

If anyone thinks this is good or even viable idea then lets implement it.  I envisioned it with just this one rule to follow - the name of the patch package would reflect the version we are patching (ie. with(patch12) or with(patch2016) for Maple 12 and Maple 2016 respectively etc...)  We could make these patch packages available in this post or start another.

As I said, I'm just throwing the idea out there.  Thoughts?

It seems a large number of people, when initially using maple, wrongly deduce that for example sin(60) is the sin of 60 degrees and not the sin of 1/3 Pi radians.  I believe mathematica's default is degrees.  When a student compares an expression to another but forgets to realize a value is read as radians and not degrees they are perplexed when Maple returns false and Mathematica returns true.

As a suggestion, under tools->options allow a user to be able to change how maple reads values within trigonometric funtions as either radians or degrees.

Most times when someone computes the sin(60) what they really mean in Maple..
is sin(convert(60 degrees, radians))

 

It appears google doesn't know about the haversine formula.  Huh?  Well at least google can't draw the proper path for it.  I typed in google "distance from Pyongyang to NewYork city"  and got 10,916km.  Ok that's fine but then it drew a map

The map path definitely did not look right.  Pulled out my globe traced a rough path of the one google showed and I got 13 inches (where 1 inch=660miles) -> 8580 miles = 13808 km .. clearly looks like google goofed. 

So we need Maple to show us the proper path.
 

with(DataSets):
with(Builtin):
m := WorldMap();
AddPath(m, [-74.0059, 40.7128], [125.7625, 39.0392]):
Display(m):

Ok so you say that really doesn't look like the shortest path.  Well, lets visualize that on the globe projection

Display(m, projection = Globe, orientation = [-180, 0, 0])

Ah, now it is clear
Pyonyang_to_NewYork.mw

 

Here's a little procedure to fish out data from the Simbad database.  Some star names may not work if the page Simbad brings up is not completely filled, but it should work for most queries.


 

restart; gc()

Simbad := proc (a::string) local b, c, c1, c2, c3, c4, c5, d1, d2, d3, d4, d5, e1, e2, e3, e4, e5; b := StringTools:-DeleteSpace(StringTools:-Substitute(a, " ", "+")); c := HTTP:-Get(cat("http://simbad.u-strasbg.fr/simbad/sim-id?Ident=", b, "&submit=submit+id")); c1 := StringTools:-Search("Parallaxes", c[2]); c2 := StringTools:-Search("Radial", c[2]); c3 := StringTools:-Search("Spectral type:", c[2]); c4 := StringTools:-Search("Gal", c[2]); c5 := StringTools:-Search("ICRS", c[2]); d1 := c[2][c1+87 .. c1+93]; d2 := c[2][c2+96 .. c2+110]; d3 := c[2][c3+77 .. c3+90]; d4 := c[2][c4+122 .. c4+140]; d5 := c[2][c5+135 .. c5+164]; e1 := d1[() .. StringTools:-Search(" ", d1)]; e2 := d2[() .. StringTools:-SearchAll(" ", d2)[2]]; e3 := d3[() .. StringTools:-Search(" ", d3)]; e4 := convert(evalf(1000/parse(e1)), 'units', 'parsec', 'ly'); e5 := d5[() .. StringTools:-Search("\n", d5)-1]; print(cat(StringTools:-Capitalize(a), "\nDistance", e4, "lightyears", "\nRight Ascension and declination:", e5, "\nGalactic coordinates", d4, "Spectral Type:", e3, "\nRadial velocity:", e2, "\nParallax", e1, "milliarcseconds")) end proc:
 

Simbad("epsilon eridani")

"Epsilon Eridani
Distance" || (10.48936700) || "lightyears" || "
Right Ascension and declination:" || "03 32 55.84496 -09 27 29.7312" || "
Galactic coordinates" || "195.8446 -48.0513
 " || "Spectral Type:" || "K2Vk: " || "
Radial velocity:" || "V(km/s) 16.43 " || "
Parallax" || "310.94 " || "milliarcseconds"

(1)

Simbad("alpha centauri")

"Alpha Centauri
Distance" || (4.395638513) || "lightyears" || "
Right Ascension and declination:" || "14 39 36.204 -60 50 08.23" || "
Galactic coordinates" || "315.7330 -00.6809
 " || "Spectral Type:" || "G2V+K1V " || "
Radial velocity:" || "V(km/s) -22.3 " || "
Parallax" || "742 " || "milliarcseconds"

(2)

Simbad("beta hydri")

"Beta Hydri
Distance" || (24.32731987) || "lightyears" || "
Right Ascension and declination:" || "00 25 45.07036 -77 15 15.2860" || "
Galactic coordinates" || "304.7720 -39.7821
 " || "Spectral Type:" || "G0V " || "
Radial velocity:" || "V(km/s) 23.10 " || "
Parallax" || "134.07 " || "milliarcseconds"

(3)

Simbad("HR6998")

"Hr6998
Distance" || (42.67386858) || "lightyears" || "
Right Ascension and declination:" || "18 38 53.40045 -21 03 06.7368" || "
Galactic coordinates" || "012.7251 -06.7965
 " || "Spectral Type:" || "G6V " || "
Radial velocity:" || "V(km/s) 36.175 " || "
Parallax" || "76.43 " || "milliarcseconds"

(4)

``


 

Download star_database_-_simbad.mw

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