Re: Very strange behaviour of ArcTan[]
- To: mathgroup at smc.vnet.net
- Subject: [mg102681] Re: [mg102656] Very strange behaviour of ArcTan[]
- From: "Tony Harker" <a.harker at ucl.ac.uk>
- Date: Tue, 18 Aug 2009 06:10:27 -0400 (EDT)
- References: <200908171206.IAA06945@smc.vnet.net>
Dear Alexey,
Why are you surprised by the output? ArcTan is doing exactly what it
should when called with two arguments:
In[1]:= ArcTan[.5, $MachinePrecision]
ArcTan[.5]
$MachinePrecision
$MachinePrecision/.5
ArcTan[%]
Out[1]= 1.53947
Out[2]= 0.463648
Out[3]= 15.9546
Out[4]= 31.9092
Out[5]= 1.53947
Tony Harker
]-> -----Original Message-----
]-> From: Alexey [mailto:lehin.p at gmail.com]
]-> Sent: 17 August 2009 13:07
]-> To: mathgroup at smc.vnet.net
]-> Subject: [mg102656] Very strange behaviour of ArcTan[]
]->
]-> Hello,
]-> I just have discovered some strange (buggy?) feature of
]-> ArcTan[] function in Mathematica 5.2. Try the following;
]->
]-> In[72]:=
]-> ArcTan[.5,$MachinePrecision]
]-> ArcTan[.5]
]->
]-> Out[72]=
]-> 1.53947
]->
]-> Out[73]=
]-> 0.463648
]->
]-> The expression ArcTan[.5,$MachinePrecision] must (?) give
]-> an error but in really gives some strange output without
]-> any error messages... What do you think about this?
]->
]->
- References:
- Very strange behaviour of ArcTan[]
- From: Alexey <lehin.p@gmail.com>
- Very strange behaviour of ArcTan[]