Re: Chop in Mathematica 8.0.1
- To: mathgroup at smc.vnet.net
- Subject: [mg117593] Re: Chop in Mathematica 8.0.1
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Thu, 24 Mar 2011 06:27:06 -0500 (EST)
Intentional or not, I don't like it. When I write 1.1 I, I do NOT imply that the real part is also approximate. Bobby On Wed, 23 Mar 2011 02:52:06 -0500, Heike Gramberg <heike.gramberg at gmail.com> wrote: > In the "Possible Issues" section in the documentation of Chop it says > that > "Machine complex numbers have machine reals for both real and imaginary > parts", and that "Consequently, Chop does not make the real part of > machine complex numbers an exact zero", so I guess it's intentional. > > Heike > > On 21 Mar 2011, at 11:12, Andrzej Kozlowski wrote: > >> Hmm... perhaps this is not a bug but a deliberate new design? >> >> Just evaluating >> >> 1.1 I >> >> returns >> >> 0. +1.1 >> >> It seems a purely cosmetic issue but it does look a rather >> "untraditional". Can anyone confirm that this is indeed an intentional >> change? >> >> Andrzej Kozlowski >> >> >> >> On 20 Mar 2011, at 12:44, Andrzej Kozlowski wrote: >> >>> Chop does not seem to work properly in Mathematica 8.0.1: >>> >>> f[a_] := 2 I Pi Sin[a]/a >>> >>> In[2]:= f[1.] >>> >>> Out[2]= 0. + 5.287118128162912*I >>> >>> In[3]:= Chop[%] >>> >>> Out[3]= 0. + 5.287118128162912*I >>> >>> This is with >>> >>> In[4]:= $Version >>> >>> Out[4]= 8.0 for Mac OS X x86 (64-bit) (February 23, 2011) >>> >>> Mathematica 7.01 returns 5.287118128162912*I as expected. >>> >>> Can anyone confirm it? At the moment I can't see any simple work >> around... >>> >>> Andrzej Kozlowski >> >> > -- DrMajorBob at yahoo.com