Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, is already up and running.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Failure to detect strings that look completely identical

From   Ronan Conroy <>
To   "" <>
Subject   Re: st: Failure to detect strings that look completely identical
Date   Wed, 23 Nov 2011 14:01:26 +0000

On 2011 Samh 22, at 19:50, Nick Cox wrote:

> The help for -charlist- (SSC) documents that char(32) and char(160)
> are hard to tell apart:
> . di "|`=char(32)'|"
> | |
> . di "|`=char(160)'|"
> | |
> So, watch out for char(160).

Your mileage may vary

Mac OS X

. di "|`=char(160)'|"

. di "|`=char(32)'|"
| |

I got caught out, years ago, by data contaminated by ASCII 30 - the infamous null character. It was used by MS Word to indicate end of file, and could sneak into data. 

. di "|`=char(30)'|"

However, if I paste this output into BBEdit and view invisibles, I can see the little horror, which BBEdit displays as a red ¿. (If your mailer hasn't shown you a Spanish inverted question mark, well, that's mailers for you.)

. di "|`=char(30)'|"

Null is particularly nasty because it has no width, so it's very hard to spot.

Ronán Conroy
Associate Professor
Division of Population Health Sciences
Royal College of Surgeons in Ireland
Beaux Lane House
Dublin 2

*   For searches and help try:

© Copyright 1996–2015 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index