Bellard's BBP-type Pi formula
1/2^6 \sum_{n=0}^\infty (-1)^n/2^{10n}
(-2^5/(4n+1) -1/(4n+3) +2^8/(10n+1) -2^6/(10n+3) -2^2/(10n+5)
-2^2/(10n+7) +1/(10n+9))
References:
[1] David H.
Bellard() -
Constructor for class org.apache.hadoop.examples.pi.math.Bellard
This is a demonstrative program, which uses DBInputFormat for reading
the input data from a database, and DBOutputFormat for writing the data
to the database.
Given a set of sorted datasets keyed with the same class and yielding
equal partitions, it is possible to effect a join of those datasets
prior to the map.
Join() -
Constructor for class org.apache.hadoop.examples.Join
This program uses map/reduce to just run a distributed job where there is
no interaction between the tasks and each task writes a large unsorted
random sequence of words.
This program uses map/reduce to just run a distributed job where there is
no interaction between the tasks and each task write a large unsorted
random binary sequence file of BytesWritable.
Maps words from line of text into 3 key-value pairs; one key-value pair for
counting the word, one for counting its length, and one for counting the
square of its length.