Re: Printing numbers

*To*: mathgroup at smc.vnet.net*Subject*: [mg54536] Re: [mg54483] Printing numbers*From*: DrBob <drbob at bigfoot.com>*Date*: Tue, 22 Feb 2005 04:24:20 -0500 (EST)*References*: <200502210844.DAA27227@smc.vnet.net>*Reply-to*: drbob at bigfoot.com*Sender*: owner-wri-mathgroup at wolfram.com

There's no reason to think ToString[123.456789] should have ten characters. In fact, it has seven: ToString[123.456789] 123.457 That's because the default display for an approximate (machine precision) number is six decimal places. It could have been 1 or 100, after all. By the time the number is given to ToString, Mathematica has stored the number AS a number and forgotten what your InputForm was. Similarly, ToString turns 1234567.89 into a two-line output taking up 22 characters: ToString[1.23456789*^6] " 6\n1.23457 10" To control display of numbers, experiment with NumberForm, PaddedForm, AccountingForm, etc. I doubt you'll be very happy with it. Bobby On Mon, 21 Feb 2005 03:44:51 -0500 (EST), Steve Gray <stevebg at adelphia.net> wrote: > 1. Can anyone tell me why these results are what they are? Neither answer is what I would expect, > which is 10. The two strings are the same length. > > Print[StringLength[ToString[123.456789]], " ", > StringLength[ToString[1234567.89]]]; > 7 22 > > 2. Is there a simple, easily available or self-evident way to get numbers printed out such that the > total number of spaces occupied by the print before the decimal point is some fixed, user-specified > amount, the number of spaces occupied after the decimal point is a different user-specified amount, > and the number of spaces following the number is a third user-specified amount. The goal is to > easily produce aligned columns of numerical printing, which would seem to be the most trivial task > in neat number printing. > For example if the function is called fprint, fprint[345.678,4,5,6] would print 4 spaces > followed by 5 character positions to the left of the point (00345 or (2 spaces)" 345", specified by > another argument), and 6 to its right. So fprint[345.678,4,5,6] would print (4 spaces)(2 > spaces)"345.678"(3 spaces), or if desired (4 spaces)(2 spaces)"345.678000"(no spaces), the total > taking up 16 positions. Also fprint[-345.678,4,5,6] would print (4 spaces)(1 space)"-345.678"(3 > spaces), also taking 16 positions, with the decimal points aligned with the first example. > Help is not that helpful, implying that I have to write one or find it somewhere. As I > recall, C provides an easy way to do this by setting arguments to Print. > Leads would be appreciated. > > Steve Gray > > > > > -- DrBob at bigfoot.com www.eclecticdreams.net

**References**:**Printing numbers***From:*Steve Gray <stevebg@adelphia.net>