Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Unit Scaling Prefixes: (was Birthday Wish)

Once upon a time there was a word processor designed for scientific
use which allowed you to switch fonts using the function keys. Two of the
fonts were mathematical symbols, another was line pieces, greeks, orator,
and a set of small type were others. It also allowed super/subscripting
using a combination of the control key and the direction arrows to shift
the cursor location and the width of the line.

On Thu, 15 Apr 1999, J. Douglas Patterson wrote:

On Thu, 15 Apr 1999, paul o johnson wrote:

Now wait a minute, Phil. All applications by all developers interpret the A key as
the Roman letter A in English fonts and as the Greek letter alpha in Symbol font,
do they not? I routinely use only three word processing applications, but this is
true in all three of them: Microsoft Word, Microsoft Powerpoint, and Adobe
Pagemaker. When I want a sigma, I type S, select it and change it to Symbol font,
and I get a sigma. To my knowledge, all applications use the same relationship
between English and Greek letters.

But even if they didn't, all applications would necessarily interpret a separate
alpha key as alpha, etc.

What am I missing?

When you type hte <A> key on your keyboard, your computer interprets that
not as the letter <a> or <A> but as binary number between 1 and 127.
There is a software key that then interprets this as a character. This
software key is the ASCII Character Code. A piece of software such as a
font module will draw a picture on screen that it associates with that
ASCII code. All of the 26 letters (upper and lower case), all of the
numbers, all of the punctuation marks, and some control-<key> characters
are assigned a specific ASCII code number which is standard across the
industry. The greek letters such as mu or sigma do not have a specific
ASCII code value. The font module "Symobol" draws the ASCII character, a,
to look like an alpha. That is the difference.


J. Douglas Patterson
Adjunct Inst of Physics & Physical Science
Office: SCI 105C
Phone: (913)469-4444 Ext. 5947
http://www.jccc.net/~dpatter

"When you are courting a nice girl an hour seems like a second.
When you sit on a red-hot cinder a second seems like an hour.
That's relativity." - Albert Einstein -