Re: Unexpected Characters Appearing in Results
- To: mathgroup at smc.vnet.net
- Subject: [mg103295] Re: [mg103263] Unexpected Characters Appearing in Results
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Sun, 13 Sep 2009 08:03:21 -0400 (EDT)
- References: <200909112357.TAA25403@smc.vnet.net>
- Reply-to: drmajorbob at yahoo.com
I upgraded to Snow Leopard, too, and there's no problem here. (Not with Mathematica so far, that is.) Bobby On Sat, 12 Sep 2009 18:57:41 -0500, Gregory Lypny <gregory.lypny at videotron.ca> wrote: > Thanks for checking, Bobby. Yes, I executed exactly what you did > below. I was thinking that it might have to do with upgrading to Snow > Leopard the other day. I've got a message in to Wolfram tech support. > See what they have to say. > > Regards, > > Gregory > > > On 2009-09-12, at 5:21 PM, DrMajorBob wrote: > >> Here's what I get at my machine (64-bit Mac OS X, Mathematica 7.0): >> >> p = {{107, 138}, {119, 129}, {104, 101}, {107, 91}, {123, 94}}; >> stdDev[x_] := Sqrt[Plus @@ (Plus[#, -Mean@x]^2 & /@ x)/Length@x] >> >> stdDev@p // N >> >> {7.53658, 19.1896} >> >> r = Differences@p/Most@p >> >> {{12/107, -(3/46)}, {-(15/119), -(28/129)}, {3/104, -(10/101)}, {16/ >> 107, 3/91}} >> >> stdDev@r // N >> >> {0.105942, 0.0893377} >> >> I don't know why you're getting those "/.10" artifacts, but I don't >> know if that's exactly what you did, either. >> >> Bobby >> >> On Sat, 12 Sep 2009 15:30:13 -0500, Gregory Lypny >> <gregory.lypny at videotron.ca> wrote: >> >>> Hi Bobby, >>> >>> Yeh, you're right. Kind of skimped on the details. Sorry about that. >>> >>> Here's some data, five observations each on the prices of two stocks. >>> First element in each is stock 1 and the second element is stock 2. >>> >>> p= {{107, 138}, {119, 129}, {104, 101}, {107, 91}, {123, 94}} >>> >>> Here's a function for computing standard deviation that goes down each >>> "column" as it were. I think a version of this was suggested on >>> MathGroup. >>> >>> stdDev[x_] := Sqrt[Plus @@ (Plus[#, -Mean@x]^2 & /@ x)/Length@x] >>> >>> The standard deviation of price is not a problem. >>> >>> {7.53658, 19.1896} >>> >>> Now I convert the prices to returns, >>> >>> (r = Differences@p/Most@p) >>> >>> {{12/107, -(3/46)}, {-(15/119), -(28/129)}, {3/104, -(10/101)}, >>> {16/107, 3/91}} >>> >>> leaving me with four observations each because of the differencing. >>> Taking the standard deviation of returns gives me >>> >>> {0.105942 \.10, 0.0893377 \.10} >>> >>> where the \.10 appears when I copy from Mathematica and paste into my >>> mail software, but in Mathematica, the \.10 appears as an exclamation >>> mark (!) with what appears to be a skinny space between it and the >>> last digit reported for each result. >>> >>> The answers for returns are correct, and the exclamation mark still >>> appears if I compute r as a numerical approximation rather than >>> rationals. Any thoughts? >>> >>> Regards, >>> >>> Gregory >>> >>> >>> >>> On 2009-09-12, at 1:47 AM, DrMajorBob wrote: >>> >>>> Details, Gregory. Details. >>>> >>>> Bobby >>>> >>>> On Fri, 11 Sep 2009 18:57:30 -0500, Gregory Lypny >>>> <gregory.lypny at videotron.ca> wrote: >>>> >>>>> Hello everyone, >>>>> >>>>> I created a function to compute standard deviation, and in some >>>>> instances it returns a result with an exclamation mark (!) at the >>>>> end, >>>>> as in >>>>> >>>>> 0.143855 ! >>>>> >>>>> When the result is copied as plain text and pasted elsewhere, it >>>>> comes >>>>> out as >>>>> >>>>> 0.143855 \.10 >>>>> >>>>> Any reason why this is happening? I recently upgraded my Mac to Snow >>>>> Leopard, and thought that might be the cause. >>>>> >>>>> Regards, >>>>> >>>>> Gregory >>>>> >>>> >>>> >>>> --DrMajorBob at yahoo.com >>> >> >> >> --DrMajorBob at yahoo.com > -- DrMajorBob at yahoo.com
- References:
- Unexpected Characters Appearing in Results
- From: Gregory Lypny <gregory.lypny@videotron.ca>
- Unexpected Characters Appearing in Results