منابع مشابه
When Do Datatypes Commute?
Polytypic programs are programs that are parameterised by type constructors (like List), unlike polymorphic programs which are parameterised by types (like Int). In this paper we formulate precisely the polytypic programming problem of \commut-ing" two datatypes. The precise formulation involves a novel notion of higher order polymorphism. We demonstrate via a number of examples the relevance a...
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We examine when a matrix whose elements are differentiable functions in one variable commutes with its derivative. This problem was discussed in a letter from Issai Schur to Helmut Wielandt written in 1934, which we found in Wielandt’s Nachlass. We present this letter and its translation into English. The topic was rediscovered later and partial results were proved. However, there are many subt...
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ژورنال
عنوان ژورنال: MATHEMATICA SCANDINAVICA
سال: 1998
ISSN: 1903-1807,0025-5521
DOI: 10.7146/math.scand.a-13839