3.03_FindingOverlaps.ipynb

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    "def overlap(a, b, min_length=3):\n",
    "    \"\"\" Return length of longest suffix of 'a' matching\n",
    "        a prefix of 'b' that is at least 'min_length'\n",
    "        characters long.  If no such overlap exists,\n",
    "        return 0. \"\"\"\n",
    "    start = 0  # start all the way at the left\n",
    "    while True:\n",
    "        start = a.find(b[:min_length], start)  # look for b's prefix in a\n",
    "        if start == -1:  # no more occurrences to right\n",
    "            return 0\n",
    "        # found occurrence; check for full suffix/prefix match\n",
    "        if b.startswith(a[start:]):\n",
    "            return len(a)-start\n",
    "        start += 1  # move just past previous match"
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    "overlap('TTACGT', 'CGTGTGC')"
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    "overlap('TTACGT', 'GTGTGC')"
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