On Thursday 13 January 2011 13:47:34 Hendrik Boom wrote:
On Thu, Jan 13, 2011 at 09:12:56AM -0500, Shawn H Corey wrote:
On 11-01-12 10:44 PM, Susan Spencer wrote:
And thanks for the heads up about 2.54cm/inch. I've been using some sewing books which make recommendations of rounding to
the
10th rather than 100th perhaps because they were using pencil& paper, and it worked well enough for them personally. This is ultimately garbage advice, so thanks for pointing that out.
It's not that the advise is complete garbage, it depends on what you want. It's just that you had 1 in = 72.72 pts, which is 4 significant digits and 1 in = 2.5 cm, which has only two. It's best to have the same number of significant digits for all your conversions. :)
I've once been told that the US is legally on the metric system and that the inch is *defined* to be 2.54 cm., which makes 2.54 exact to as many decimal places as you want. I'd like to know if this is actually true. Anybody know?
-- hendrik
That's the definition in all my (old) textbooks, like the Chemical Rubber Company's "Abridged Math Tables" of 1964. But TeX has a definition of a printer's point that antedates our current standard of 72 per inch. The TeX definition is 72.27 per inch. Apparently Adobe established the newer standard. Tex calls the Adobe point a "big point" (bp).