MaplePrimes - Maple 7 Posts and Questions

Bug in old version (Maple 7, Mellin Transform)

wodije — Mon, 12 May 2025 05:23:32 Z

I'm using an old old version of Maple (Maple 7) and there's a mistake in the Mellin Transform which hopefully has long since been fixed in subsequent versions but just in case it hasn't....

I was taking the Mellin Transform of Bessel Functions, specifically BesselK, and it's fine for BesselK(0,x), but when I compute BesselK(0,x^{1/2}), it gives the wrong answer.

In the transform of BesselK(0,x^(1/2)), It should be Gamma(p) not Gamma(p/2).

Maple 7 crashing when i saving

logan35 — Wed, 14 Sep 2022 11:42:32 Z

when i try to save my program maple is close, crashing. how can i fix this?

How can i do convert numbers for binary 8 bytes and plot histogram?

logan35 — Sat, 07 May 2022 09:28:57 Z

Hello, i want to do convert numbers to binary code 8 bytes and I want to sum the digits of each number

For example first number is 0 i want to write 0 0 0 0 0 0 0 0 , sum=0, for 1= 0 0 0 0 0 0 0 1, sum =1 for 7= 0 0 0 0 0 1 1 1 sum=3 etc.....
my code is this;

for i from 0 to 10 do;
> S(i):=convert(i,binary);
> end do;

and output is

S(0) := 0
S(1) := 1
S(2) := 10
S(3) := 11
S(4):=100
S(5) := 101
S(6) := 110
S(7) := 111
S(8) := 1000
S(9) := 1001
S(10) := 1010
and Histogram(S(i)); doesnt work.

In whitch folder are the datafiles saved by "save"

serge17 — Sun, 21 Jun 2020 14:24:44 Z

Hello

After
> save mytable, "foo.m";
in whitch folder may I find the file "foo.m" ?

I try with the function "search" of Windows 10, but it can't find it.

Thanks for a answer.

Serge

Maple and two light sources

Christopher2222 — Sun, 24 Nov 2019 17:44:34 Z

There was a discussion regarding Maple and two light sources a couple of days ago (unfortunately the content of that conversation has been removed by the original poster so if any of you thought you were getting early signs of alzheimers, rest assured the questions/posts were indeed there and you can all put your memories at ease for a little).

I did indeed go back into Maple to see how far it was that we lost the two light source capability. I can tell you that as far back as Maple 10.06 dual (or more) light sources was not working. So I worked my way up - of course the OP of the deleted questions mentioned Maple Vr4 (I think), so I started there. Maple 6 and Maple 7 is ok. I was unable to check Maple 8 and 9 as my computers with that software are currently missing (probably buried in my shed somewhere - as long as the wife hasn't got rid of them.. anyways)

So I'll share with you what once was. From Maple 7, and an animated gif (which hopefully works) to illustrate two light sources (one brown light, and one mauve or purple light) and what it looked like from Maple 7.

with(plots):
setoptions3d(style=patchnogrid,projection=.9):
a:=plot3d(-x^2-y^2-x*y,x=-1..1,y=-1..1,color=[.5,.9,.9],grid=[15,15]):
b:=n->display(a,orientation=[n,60]):
display([seq(b(10*n),n=0..35)],light=[90,-80,1,.2,.1],light=[90,40,1,.5,.8],insequence=true);

The animation is not working so the uploaded gif file is here for you to check out. .. Couldn't upload the gif file so I've zipped it - that worked

twolightsource.zip

Writing text using textprint=true withe the draw command

das1404 — Sat, 30 Mar 2019 04:50:29 Z

simplify_question.mws
Am trying to teach myself about lines and circles and inversion. In the code below I'd like to put textt on the circles eg c1 to identify circle c1 etc.I'm more familiar with the textplot command & plottools, but want to use the draw command. I've tried some options with the circle statement without success.
circle(c1,x^2+(y-2*R*cos(Pi/6))^2=R^2): # 'ctext'=c1):

Is it possible to position text in a draw statement, similar to the textplot statement (that uses plot)?

I was amused by an idiosincracy of Maple 7. The last line of my code uses the simplify command, yet I have had to resort to the simplification myself - (on the previous lines). I was surprised and curious about this. The Help section on simplify mentions several high power simplification procedures, yet fails to simplify a simple expression. Any comments on this?

I'm interested in learning more about circle inversion and wondered if anyone knew of some elementary books on this. Geometry Inversion was never taught to me at school, nor university, despite it being a topic over 1000 years old.

Thanks for your time. Any comments, answers, gladly appreciated.

restart:
# # # # # # # # # # # # # # # # # # # # # # # # # # # #
# Test of geometry, radical axis.
# # # # # # # # # # # # # # # # # # # # # # # # # # # #
with(geometry):
with(plots):
_EnvHorizontalName := x: _EnvVerticalName := y:

R:=5:
circle(c1,x^2+(y-2*R*cos(Pi/6))^2=R^2): # 'ctext'=c1):
circle(c2,(x-R)^2+y^2=R^2):
circle(c3,(x+R)^2+y^2=R^2):
RadicalAxis(ra12,c1,c2):
RadicalAxis(ra13,c1,c3):

printf("Colors: c1=red c2=blue c3=gold\n");
printf(" ra12=magenta ra23=grey\n");
t1:=textplot([0, 1.8*R, `Circle c1`]):
draw([c1,c2, c3, ra12,ra13], axes=normal, color=[red, blue,gold, magenta,grey]);

#draw([c1,c2, c3, ra12,ra13,t1], axes=normal, color=[red, blue,gold, magenta,grey, black], printtext=true);
if AreTangent(c1,c2) then
printf("Circles c1 and c2 are tangential, (as they all are!)\n");
end if:
testp:=Equation(ra12):
#print(whattype(testp));
printf("Equation of radical axis for c1 & c2 is %A or\n", testp);
simplify(Equation(ra12)/10);
simplify(Equation(ra12));

Warning, the name changecoords has been redefined

Colors: c1=red c2=blue c3=gold

ra12=magenta ra23=grey

Circles c1 and c2 are tangential, (as they all are!)

Equation of radical axis for c1 & c2 is 50+10*x-10*3^(1/2)*y = 0 or

Download simplify_question.mws