Re: From PaddedForm to numbers?

*To*: mathgroup at smc.vnet.net*Subject*: [mg80514] Re: From PaddedForm to numbers?*From*: AES <siegman at stanford.edu>*Date*: Fri, 24 Aug 2007 01:55:45 -0400 (EDT)*Organization*: Stanford University*References*: <faj6fp$9gt$1@smc.vnet.net> <fajn99$pb1$1@smc.vnet.net>

In article <fajn99$pb1$1 at smc.vnet.net>, David Bailey <dave at Remove_Thisdbailey.co.uk> wrote: > PaddedForm is a wrapper - like MatrixForm, and many others. WRI have a > standard comment in relation to these - "PaddedForm acts as a ?wrapper?, > which affects printing, but not evaluation." > > The wording of this has always seemed to me unfortunate, because if you > leave wrapper round an object it looks OK, but can't be incorporated in > a further calculation - in other words a wrapper certainly does affect > evaluation! Amen. Been caught by this repeatedly with TableForm -- especially if it's something like Table[ - - lengthy expression - - ]//TableForm. If the standard comment were changed to something like " . . . affects printing, but not evaluation *of the expression inside the wrapper*", you'd at least. By the way, if my test in 5.2 the other day was correct, x=7; PaddedForm[x, 3, NumberForm->{"0",""} ] produces 0007 -- which doesn't match my naive interpretation of "padding something out to three significant figures", especially since it expresses x = 7777 correctly as *four* significant figures. (It doesn't make James Bond very happy either).