vv

6533 Reputation

18 Badges

4 years, 81 days

MaplePrimes Activity


These are questions asked by vv

combine(2^n*4, icombine);

2^(2+n)

(1)

combine(2^n*4);

4*2^n

(2)

combine(2^n/4, icombine); # BUG

Error, (in compat) invalid input: igcd received undefined, which is not valid for its 2nd argument

 

combine(2^n/4);

(1/4)*2^n

(3)

combine(2^n/2^m, icombine); # BUG

Error, (in compat) invalid input: igcd received undefined, which is not valid for its 2nd argument

 

combine(2^n*2^(-m), icombine);

2^(n-m)

(4)

combine(2^n/2^m);

2^(n-m)

(5)

is(2^n/4 = 2^(n-2)); # ???

false

(6)

 


Download bug-icombine-is.mw

The  plots help page contains an entry for ternaryplot. But it is empty (Maple 2018&2019) and there is no such command.
Does somebody know about it?

searchtext and SearchText do not work well with non-ASCII characters.
Strangely, StringTools:-Search is OK.

restart;
m:=convert([77,97,116,104,195,169,109,97,116,105,113,117,101], bytes);
                      m := "Mathématique"
seq(searchtext(m[i..7], m), i=1..7);
                      1, 0, 0, 4, 0, 0, 1
seq(SearchText(m[i..7], m), i=1..7);
                      1, 0, 0, 4, 0, 0, 7
seq(StringTools:-Search(m[i..7], m), i=1..7);
                      1, 2, 3, 4, 5, 6, 7

 

Some mathematical functions and also some (not so) inert functions are implemented as objects.
For example, Perm is used to represent permutations.

p :=Perm([2,3,1,5,4]);  # ==> disjoint cycles representation
        p:=(1,2,3)(4,5);
lprint(p);
Perm([[1, 2, 3], [4, 5]])
    
Perm acts as an inert function (like RootOf) but it's an object.
Is it possible to convert it into a true inert form such as PERM([[1, 2, 3], [4, 5]]) and so, being able to extract the arguments with op?  

In this specific case we may use
convert(p, disjcyc);
       [[1, 2, 3], [4, 5]]
    
but this is possible only because Perm has a convert export.
So, is it possible to obtain the arguments directly (without convert)?
This would be useful for other situations.

If I copy the output of a lprint command e.g.
lprint(<1,2;3,4>);

Matrix(2,2,{(1, 1) = 1, (1, 2) = 2, (2, 1) = 3, (2, 2) = 4},datatype = anything
,storage = rectangular,order = Fortran_order,shape = [])

and paste it in a new execution group, I obtain a "Line print output" instead of a Maple (1D) input,
so it cannot be executed.
(Of course, it's possible to paste in Notepad to remove the format, but it's annoying.)

This happens in Maple 2019,  Windows 64, Worksheet mode, 1D input;  but not all the time (sometimes it is as it used to be).
Do you see the same behavior?

 

1 2 3 4 5 6 7 Last Page 1 of 10