Implement NgramMap service

[s-bose7]

NgramMap API

The NGramMap class will provide various convenient methods for interacting with Google’s NGrams dataset.

Input File Formats:

The NGram dataset comes in two different file types. The first type is a “words file”. Each line of a words file provides tab separated information about the history of a particular word in English during a given year. i.e.

Word        Year    Occurrence     Sources
airport     2007    175702         32788
airport     2008    173294         31271
request     2005    646179         81592
request     2006    677820         86967
request     2007    697645         92342
request     2008    795265         125775
wandered    2005    83769          32682
wandered    2006    87688          34647
wandered    2007    108634         40101
wandered    2008    171015         64395

The other type of file is a “counts file”. Each line of a counts file provides comma separated information about the total corpus of data available for each calendar year. i.e.

Year, Total words, Total pages, Sources 
1470,    984,         10,         1
1472,    117652,      902,        2
1475,    328918,      1162,       1
1476,    20502,       186,        2
1477,    376341,      2479,       2

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