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Edit detail for #313 sqrt(x,0) should not give 1 in RealClosedField revision 1 of 2

1 2
Editor:
Time: 2007/11/17 22:25:04 GMT-8
Note: wrong library

changed:
-
The file algebra/reclos.spad.pamphlet (line 369) contains the definition

sqrt(x,n) == n = 0 => 1 ...

This function should represent x^(1/n), which does not go to 1 as n goes to infinity. In fact, algebraically y = x^(1/0) would represent the solution of y^0 = x, which has no solution unless x is 1. So the result should be undefined for n=0. Restricting the domain of n to Positive integer should do the trick.

Similarly, on line 412 of the same file, there is a similarly erroneous definition

nthRoot(x,n) == zero?(n) => x ...

From BillPage Fri Aug 24 15:02:16 -0500 2007
From: Bill Page
Date: Fri, 24 Aug 2007 15:02:16 -0500
Subject: wrong library
Message-ID: <20070824150216-0500@wiki.axiom-developer.org>

Category: Aldor Library Compiler => Axiom Library 


Submitted by : (unknown) at: 2007-11-17T22:25:04-08:00 (17 years ago)
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The file algebra/reclos.spad.pamphlet (line 369) contains the definition

sqrt(x,n) == n = 0 => 1 ...

This function should represent x^(1/n), which does not go to 1 as n goes to infinity. In fact, algebraically y = x^(1/0) would represent the solution of y^0 = x, which has no solution unless x is 1. So the result should be undefined for n=0. Restricting the domain of n to Positive integer should do the trick.

Similarly, on line 412 of the same file, there is a similarly erroneous definition

nthRoot(x,n) == zero?(n) => x ...

wrong library --Bill Page, Fri, 24 Aug 2007 15:02:16 -0500 reply
Category: Aldor Library Compiler => Axiom Library