diff options
Diffstat (limited to 'search/index/index.go')
-rw-r--r-- | search/index/index.go | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/search/index/index.go b/search/index/index.go new file mode 100644 index 0000000..81b50e0 --- /dev/null +++ b/search/index/index.go @@ -0,0 +1,165 @@ +package index + +import "fmt" +import "os" +import "io" +import "bufio" +import "sort" +import "errors" +import "strings" +import "strconv" + +/* TODO + + - Implement Forward Creation + - Implement Inverted from Forward + - Switch Indexer.go over to this package + +/********* + * Types * + *********/ + +type f_info struct { + word string; + in_title bool; + freq float64; +}; + +type i_info struct { + doc string; + in_title bool; + freq float64; +}; + +type f_entry struct{ + this *f_info; + next *f_entry; +}; + +type i_entry struct{ + this *i_info; + next *i_entry; +}; + +type F_index map[string]*f_entry; +type I_index map[string]*i_entry; + +type sortInverted struct{ + w string; + root *i_entry; +}; + + +/*************************** + * Forward Index Funcitons * + ***************************/ + +func NewForwardEntryStrings(text, title []string) (*f_entry, error) { + return nil, errors.New("not implemented"); +} + +/**************************** + * Inverted Index Functions * + ****************************/ + +func new_i_info() *i_info{ + return &i_info{"", false, 0.0}; +} + +func NewInvertedIndexFromFile(fname string) (I_index, error) { + var fd *os.File; + var br *bufio.Reader; + var err error; + var buf []byte; + var tmp *i_info; + var cur *i_entry; + var index I_index; + var word string + var info []string; + + fd, err = os.Open(fname); + if err != nil { + return nil, err; + } + + br = bufio.NewReader(fd); + if br == nil { + return nil, errors.New("Could not initialize reader"); + } + + index = make(I_index); + + for buf, err = br.ReadBytes('\n'); err != io.EOF; buf, err = br.ReadBytes('\n'){ + tmp = new_i_info(); + if err != nil { + return nil, err; + } + if buf[0] != '\t' { + word = strings.TrimSpace(string(buf)); + } else { + info = strings.Fields(string(buf)); + tmp.doc = info[0]; + tmp.in_title = (info[1] == "1"); + tmp.freq, _ = strconv.ParseFloat(info[2], 32); + if (index[word] == nil) { + index[word] = &i_entry{this: tmp, next: nil}; + } else { + cur = index[word]; + for cur.next != nil { + cur = cur.next; + } + cur.next = &i_entry{this: tmp, next: nil}; + } + } + } + + return index, nil; +} + +func NewInvertedFromForward(f F_index) (I_index, error) { + return nil, errors.New("not implemented"); + +} + +func (x I_index) PrintToFile(fd *os.File) error{ + var i int; + var cur *i_entry; + var index []sortInverted; + + index = x.sortIndex(); + + for i = 0; i < len(index); i++ { + fmt.Fprintf(fd, "%s\n", index[i].w); + for cur = index[i].root; cur != nil; cur = cur.next { + fmt.Fprintf(fd, "\t%s %d %.3f\n", cur.this.doc, toInt(cur.this.in_title), cur.this.freq); + } + } + return nil; +} + +func toInt(t bool) int{ + if (t){ + return 1; + } + return 0; +} + +func (unsort I_index) sortIndex() []sortInverted { + var i int; + var sorted []sortInverted; + + sorted = make([]sortInverted, len(unsort)); + + i = 0; + for k, v := range unsort { + sorted[i].w = k; + sorted[i].root = v; + i++; + } + + sort.Slice(sorted, func(i, j int) bool { + return sorted[i].w < sorted[j].w; + }); + + return sorted +} |