TY - GEN
T1 - Approximating general metric distances between a pattern and a text
AU - Porat, Ely
AU - Efremenko, Klim
PY - 2008/1/1
Y1 - 2008/1/1
N2 - Let T = t0 ... tn-1 be a text and P = p0 ... pm-1 a pattern taken from some finite alphabet set Σ, and let d be a metric on Σ. We consider the problem of calculating the sum of distances between the symbols of P and the symbols of substrings of T of length m for all possible offsets. We present an ε-approximation algorithm for this problem which runs in time O(1/ε2n · polylog(n, |Σ|)). This algorithm is based on a low distortion embedding of metric spaces into normed spaces (especially, into l∞), which is done as a preprocessing stage. The algorithm is also based on a technique of sampling.
AB - Let T = t0 ... tn-1 be a text and P = p0 ... pm-1 a pattern taken from some finite alphabet set Σ, and let d be a metric on Σ. We consider the problem of calculating the sum of distances between the symbols of P and the symbols of substrings of T of length m for all possible offsets. We present an ε-approximation algorithm for this problem which runs in time O(1/ε2n · polylog(n, |Σ|)). This algorithm is based on a low distortion embedding of metric spaces into normed spaces (especially, into l∞), which is done as a preprocessing stage. The algorithm is also based on a technique of sampling.
UR - http://www.scopus.com/inward/record.url?scp=58049090635&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:58049090635
SN - 9780898716474
T3 - Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms
SP - 419
EP - 427
BT - Proceedings of the 19th Annual ACM-SIAM Symposium on Discrete Algorithms
PB - Association for Computing Machinery
T2 - 19th Annual ACM-SIAM Symposium on Discrete Algorithms
Y2 - 20 January 2008 through 22 January 2008
ER -