Alec Mihailovs

Dr. Aleksandrs Mihailovs

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19 years, 191 days
Mihailovs, Inc.
Owner, President, and CEO
Tyngsboro, Massachusetts, United States

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I received my Ph.D. from the University of Pennsylvania in 1998 and I have been teaching since then at SUNY Oneonta for 1 year, at Shepherd University for 5 years, at Tennessee Tech for 2 years, at Lane College for 1 year, and this year I taught at the University of Massachusetts Lowell. My research interests include Representation Theory and Combinatorics.

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These are Posts that have been published by Alec Mihailovs

?subgrel page contains an interesting error example with a very short syllable c. It looks more interesting with other syllables,

    grelgroup({a,b}, {[a,a], [b,a]}));

Error, (in subgrel) generator [a, b, averylongsyllable] 
contains a syllable `averylongsyllable' that is not a generator, 
or the inverse of a generator, of the parent group


kernelopts(toolboxdir) crashes mserver both in Classic and Standard Maple 12 on Windows Vista (I didn't check the command line).


I just looked how differential forms are implemented and was quite surprized

a:=evalDG(dx &wedge dy+2*dy &wedge dz):

_DG([["form", M, 2], [[[1, 2], 1], [[2, 3], 2]]])

It is an unevaluated function with nested lists as arguments.

Probably, not the worst possible choice since I can imagine few choices that would be worse - strings, for instance. But there are so many other choices that seem much better - antisymmetric Arrays, or tables, for instance. Why lists?


Multiplication by 0 gives 0 for differential forms, which is wrong. For example,

a:=dx &wedge dy: 
                              3 dx ^ dy

It should be 0 dx^dy.

That reminds me of an old Matrix bug with M^0 being 1 instead of the identity Matrix for square Matrices.


I just noticed that usual parentheses work as square brackets for Matrices,


                                 [a    b]
                            M := [      ]
                                 [c    d]
                                b = b

That leads to the following,

Error, unsupported type of index, x

while that worked OK for matrices,

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