google`AppEngine file system intro

2.20: news.adda/co/google`AppEngine file system intro:
G'AppEngine`concepts:
. projects store objects in buckets
which are like folders but non-nestable;
and have names that are unique across
not just the project but all of g'storage .
. immutability applies only to objects
not filenames, [symbolic vs hard links].
Object names can contain
any combination less than 1024 bytes,
of Unicode characters (UTF-8 encoded)
including "/"
so that you can use old pathnames
while google sees the entire path as one filename,
as the only hierarchy is
(g'storage, some-bucket, some-pathname).
For most operations you can use either of
the following URLs to access an object:
storage.googleapis.com/≺bucket>/≺object>
≺bucket>.storage.googleapis.com/≺object>
www.googleapis.com/storage/v1beta2/b/≺bucket>/o/≺object>?alt=media (JSON API)

the value of constants

2.20: news.adda/co/the value of constants:
11.30: summary:
. in classical programming constants are encouraged
because it simplifies the programming space:
you are no longer concerned with
accidently modifying a constant object
because the compiler or the hardware
will automatically detect that mistake for you .
. constants have even more usefulness
in the context of cloud computing .

euler's number derived from pyramid of additions

2.9: math/euler's number derived from pyramid of additions:
. "( if s#n is the product of the terms in the nth row;
) it shows a pyramid of numbers
but doesn't say how the numbers are generated .
. so there are rows with a list of terms,
and the product means
multiply all numbers in row n to get s#n .
s#(n-1)* s#(n+1) /s#n ^2 = e .
say n=7, s#n = 162000,
s#(n-1) = 2500
s#(n+1) = 26471025 .
(26471025 * 2500) / (162000* 162000) = 2.52
e = 2.7
. I can see how the pyramid is formed:
put 1's down the sides,
then for each adjacent pair in a row,
eg, for 1 2 1
see the pairs (1 2) (2 1)
add the pair and put the result between them
on the row below: 1 3 3 1 .