1srf_index_hash(1) Staden io_lib srf_index_hash(1)
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6 srf_index_hash - Adds a hash-table index to an SRF file.
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10 srf_index_hash [-c] srf_archive
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14 srf_index_hash adds and index to an SRF file or replaces an existing
15 index with a new one. In the case of concatenated SRF files only the
16 index at the end of a file will be replaced, but internal indices will
17 not be consulted by SRF tools.
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19 The index is a hash table indexing the sequence names only. The name
20 itself does not appear in the index, rather the top 7-bits of a 64-bit
21 hash key are held in the index along with N-bits used to determine the
22 hash bucket. This reduces the index size to around 10-15 bytes per
23 sequence.
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27 -c Check only. This requests that the index is not produced, but
28 the checks performed during the creation of an index (such as
29 looking for duplicate sequence names) are still performed.
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33 James Bonfield, Wellcome Trust Sanger Institute
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37 September 29 srf_index_hash(1)