Sorting Arrays

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#
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# Like GNU awk's asort() but works with any awk(1)
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# NB: Named _asort() to prevent conflict with GNU awk
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#
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function _asort(src, dest)
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{
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        k = nitems = 0
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        for (i in src) dest[++nitems] = src[i]
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        for (i = 1; i <= nitems; k = i++) {
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                val = dest[i]
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                while ((k > 0) && (dest[k] > val)) {
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                        dest[k+1] = dest[k]; k--
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                }
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                dest[k+1] = val
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        }
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        return nitems
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}
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​
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# Sample _asort() usage:
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############################################################
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#
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#    string = "abc,123"
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#    split(string, array, /,/)
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#    n = _asort(array, sorted_array)
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#    sorted_string = ""
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#    for (i = 1; i <= n; i++)
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#        sorted_string = sorted_string "," sorted_array[i]
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#    sub(/^,/, "", sorted_string)
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#    print sorted_string # produces "123,abc"
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#
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############################################################
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​
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#
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# Like GNU awk's asorti() but works with any awk(1)
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# NB: Named _asorti() to prevent conflict with GNU awk
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#
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function _asorti(src, dest)
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{
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        k = nitems = 0
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        for (i in src) dest[++nitems] = i
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        for (i = 1; i <= nitems; k = i++) {
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                idx = dest[i]
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                while ((k > 0) && (dest[k] > idx)) {
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                        dest[k+1] = dest[k]; k--
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                }
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                dest[k+1] = idx
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        }
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        return nitems
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}
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​
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# Sample _asorti() usage:
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############################################################
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#
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#    foo["abc"] = 1 # value ignored
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#    foo["123"] = 1 # value ignored
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#    n = _asorti(foo, sorted_indices)
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#    for (i = 1; i <= n; i++)
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#        print sorted_indices[i]
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#    # Output Produced:
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#    #       123
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#    #       abc
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#
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############################################################
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