March 30, 2018 Friday
Bedtime Story
Note D of Ada Lovelace - 2
We are continuing tonight with Note D of
Ada Lovelace.
“In all calculations, the columns of
Variables used may be divided into three classes:-
1st. Those on which the data are
inscribed:
2ndly. Those intended to receive the final
results:
3rdly. Those intended to receive such
intermediate and temporary combinations of the primitive data as are not to be
permanently retained, but are merely needed for working with, in order to
attain the ultimate results.
Combinations of this kind might properly be
called secondary data.
They are in fact so many successive stages
towards the final result.
The columns which receive them are rightly
named Working-Variables, for their office is in its nature purely subsidiary to
other purposes.
They develop an intermediate and transient
class of results, which unite the original data with the final results.
The Result-Variables sometimes partake of
the nature of Working-Variables.
It frequently happens that a Variable
destined to receive a final result is the recipient of one or more intermediate
values successively, in the course of the processes.
Similarly, the Variables for data often
become Working-Variables, or Result-Variables, or both in succession.
It so happens, however, that in the case of
the present equations the three sets of offices remain throughout perfectly
separate and independent.
It will be observed, that in the squares
below the Working-Variables nothing is inscribed.
Any one of these Variables is in many cases
destined to pass through various values successively during the performance of
a calculation (although in these particular equations no instance of this
occurs).
Consequently no one fixed symbol, or
combination of symbols, should be considered as properly belonging to a merely
Working-Variable; and as a general rule their squares are left blank.
Of course in this, as in all other cases
where we mention a general rule, it is understood that many particular
exceptions may be expedient.
In order that all the indications contained
in the diagram may be completely understood, we shall now explain two or three
points, not hitherto touched on.
When the value on any Variable is called
into use, one of two consequences may be made to result.
Either the value may return to the Variable
after it has been used, in which case it is ready for a second use if needed;
or the Variable may be made zero.
(We are of course not considering a third
case, of not unfrequent occurrence, in which the same Variable is destined to
receive the result of the very operation which it has just supplied with a
number.)”
Stay tuned to the voice of an average story storytelling
chimpanzee or login at http://panarrans.blogspot.com
Good night mon ami and my fellow cousin ape.
Advertisements
Another great educator and a teacher that I am aware of is
Professor Subhashish Chattopadhyay in Bangalore, India.
While I narrate stories, Professor Subhashish an electronic
engineer and a former professor at BARC, does and teaches real mathematics and
physics.
He started the participation of Indian students at the
International Physics Olympiad.
Do visit him here:
All his books can be downloaded for free through this link:
For edutainment and English education of your children, I
recommend this large collection of Halloween Songs for Kids:
No comments:
Post a Comment