Suffix Array - Space Efficiency

Space Efficiency

Suffix arrays were introduced by Manber & Myers (1990) in order to improve over the space requirements of suffix trees: Suffix arrays store integers. Assuming an integer requires bytes, a suffix array requires bytes in total. This is significantly less than the bytes which are required by a careful suffix tree implementation.

However, in certain applications, the space requirements of suffix arrays may still be prohibitive. Analyzed in bits, a suffix array requires space, whereas the original text over an alphabet of size does only require bits. For a human genome with and the suffix array would therefore occupy about 16 times more memory than the genome itself.

Such discrepancies motivated a trend towards compressed suffix arrays and BWT-based compressed full-text indices such as the FM-index. These data structures require only space within the size of the text or even less.

Read more about this topic:  Suffix Array

Famous quotes containing the words space and/or efficiency:

    Let the space under the first storey be dark, let the water
    lap the stone posts, and vivid green slime glimmer
    upon them; let a boat be kept there.
    Denise Levertov (b. 1923)

    “Never hug and kiss your children! Mother love may make your children’s infancy unhappy and prevent them from pursuing a career or getting married!” That’s total hogwash, of course. But it shows on extreme example of what state-of-the-art “scientific” parenting was supposed to be in early twentieth-century America. After all, that was the heyday of efficiency experts, time-and-motion studies, and the like.
    Lawrence Kutner (20th century)