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Edit detail for #333 asin 1.0 over Complex Float fails revision 2 of 2

1 2
Editor: kratt6
Time: 2007/12/20 02:09:52 GMT-8
Note: See #138

added:

From kratt6 Thu Dec 20 02:09:52 -0800 2007
From: kratt6
Date: Thu, 20 Dec 2007 02:09:52 -0800
Subject: See #138
Message-ID: <20071220020952-0800@axiom-wiki.newsynthesis.org>

Category: Axiom Mathematics => Axiom Library 
Status: open => duplicate 


Submitted by : (unknown) at: 2007-11-17T22:28:24-08:00 (14 years ago)
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The first real calculus is right, the second fails.

axiom
asin 1.0

\label{eq1}1.5707963267948966192(1)
Type: Float
axiom
asin (1.0+0*%i)
>> Error detected within library code: catdef: division by zero

The problem is perhaps line 162 of trigcat.spad. There is no test for the ... / sqrt (1-x^2) in asin definition.

asin x == atan(x/sqrt(1-x**2))

patch possible. --Francois Maltey, Fri, 05 Jan 2007 07:57:48 -0600 reply
I propose to remplace in asin x == atan (x/sqrt(1-x**2)) in trigcat.spad line 162 by

asin x == x=1 => 2atan 1 x=-1 => -2atan 1 atan(x/sqrt(1-x**2))

The result seems right...

Category: Axiom Mathematics => Axiom Library Status: open => duplicate