// // Metaphone.cc // // Implementation of Metaphone // // // #include "Metaphone.h" #include #include "Dictionary.h" //***************************************************************************** // Metaphone::Metaphone() // Metaphone::Metaphone() { name = "metaphone"; } //***************************************************************************** // Metaphone::~Metaphone() // Metaphone::~Metaphone() { } //***************************************************************************** // void Metaphone::generateKey(char *word, String &key) // /* * This code was copied from the slapd package developed at umich. * it was debugged and cleaned up in February 1999 by Geoffrey Hutchison * for the ht://Dig Project. */ /* * Metaphone copied from C Gazette, June/July 1991, pp 56-57, * author Gary A. Parker, with changes by Bernard Tiffany of the * University of Michigan, and more changes by Tim Howes of the * University of Michigan. */ /* Character coding array */ static char vsvfn[26] = { 1, 16, 4, 16, 9, 2, 4, 16, 9, 2, 0, 2, 2, /* A B C D E F G H I J K L M */ 2, 1, 4, 0, 2, 4, 4, 1, 0, 0, 0, 8, 0}; /* N O P Q R S T U V W X Y Z */ /* Macros to access character coding array */ #define vscode(x) ((x) >= 'A' && (x) <= 'Z' ? vsvfn[(x) - 'A'] : 0) #define vowel(x) ((x) != '\0' && vscode(x) & 1) /* AEIOU */ #define same(x) ((x) != '\0' && vscode(x) & 2) /* FJLMNR */ #define varson(x) ((x) != '\0' && vscode(x) & 4) /* CGPST */ #define frontv(x) ((x) != '\0' && vscode(x) & 8) /* EIY */ #define noghf(x) ((x) != '\0' && vscode(x) & 16) /* BDH */ #define MAXPHONEMELEN 6 void Metaphone::generateKey(char *word, String &key) { if (!word || !*word) return; char *n; String ntrans; /* * Copy Word to internal buffer, dropping non-alphabetic characters * and converting to upper case */ ntrans << "0000"; for (; *word; word++) { if (isalpha(*word)) ntrans << *word; } ntrans.uppercase(); /* ntrans[0] will always be == 0 */ n = ntrans.get(); *n++ = 0; *n++ = 0; *n++ = 0; *n = 0; /* Pad with nulls */ n = ntrans.get() + 4; /* Assign pointer to start */ /* Check for PN, KN, GN, AE, WR, WH, and X at start */ switch (*n) { case 'P': case 'K': case 'G': /* 'PN', 'KN', 'GN' becomes 'N' */ if (*(n + 1) == 'N') *n++ = 0; break; case 'A': /* 'AE' becomes 'E' */ if (*(n + 1) == 'E') *n++ = 0; break; case 'W': /* 'WR' becomes 'R', and 'WH' to 'W' */ if (*(n + 1) == 'R') *n++ = 0; else if (*(n + 1) == 'H') { *(n + 1) = *n; *n++ = 0; } break; case 'X': /* 'X' becomes 'S' */ *n = 'S'; break; } /* * Now, loop step through string, stopping at end of string or when * the computed 'metaph' is MAXPHONEMELEN characters long */ for (; *n && key.length() < MAXPHONEMELEN; n++) { /* Drop duplicates except for CC */ if (*(n - 1) == *n && *n != 'C') continue; /* Check for F J L M N R or first letter vowel */ if (same(*n) || *(n - 1) == '\0' && vowel(*n)) key << *n; else { switch (*n) { case 'B': /* * B unless in -MB */ if (*(n + 1) || *(n - 1) != 'M') key << *n; break; case 'C': /* * X if in -CIA-, -CH- else S if in * -CI-, -CE-, -CY- else dropped if * in -SCI-, -SCE-, -SCY- else K */ if (*(n - 1) != 'S' || !frontv(*(n + 1))) { if (*(n + 1) == 'I' && *(n + 2) == 'A') key << 'X'; else if (frontv(*(n + 1))) key << 'S'; else if (*(n + 1) == 'H') key << (((*(n - 1) == '\0' && !vowel(*(n + 2))) || *(n - 1) == 'S') ? 'K' : 'X'); else key << 'K'; } break; case 'D': /* * J if in DGE or DGI or DGY else T */ key << ((*(n + 1) == 'G' && frontv(*(n + 2))) ? (char) 'J' : (char) 'T'); break; case 'G': /* * F if in -GH and not B--GH, D--GH, * -H--GH, -H---GH else dropped if * -GNED, -GN, -DGE-, -DGI-, -DGY- * else J if in -GE-, -GI-, -GY- and * not GG else K * */ if ((*(n + 1) != 'G' || vowel(*(n + 2))) && (*(n + 1) != 'N' || (*(n + 1) && (*(n + 2) != 'E' || *(n + 3) != 'D'))) && (*(n - 1) != 'D' || !frontv(*(n + 1)))) if (frontv(*(n + 1)) && *(n + 2) != 'G') key << 'J'; else key << 'K'; else if (*(n + 1) == 'H' && !noghf(*(n - 3)) && *(n - 4) != 'H') key << 'F'; break; case 'H': /* * H if before a vowel and not after * C, G, P, S, T else dropped */ if (!varson(*(n - 1)) && (!vowel(*(n - 1 )) || vowel(*(n + 1)))) key << 'H'; break; case 'K': /* * dropped if after C else K */ if (*(n - 1) != 'C') key << 'K'; break; case 'P': /* * F if before H, else P */ key << (*(n + 1) == 'H' ? (char) 'F' : (char) 'P'); break; case 'Q': /* * K */ key << 'K'; break; case 'S': /* * X in -SH-, -SIO- or -SIA- else S */ key << ((*(n + 1) == 'H' || (*(n + 1) == 'I' && (*(n + 2) == 'O' || *(n + 2) == 'A'))) ? (char) 'X' : (char) 'S'); break; case 'T': /* * X in -TIA- or -TIO- else 0 (zero) * before H else dropped if in -TCH- * else T */ if (*(n + 1) == 'I' && (*(n + 2) == 'O' || *(n + 2) == 'A')) key << 'X'; else if (*(n + 1) == 'H') key << '0'; else if (*(n + 1) != 'C' || *(n + 2) != 'H') key << 'T'; break; case 'V': /* * F */ key << 'F'; break; case 'W': /* * W after a vowel, else dropped */ case 'Y': /* * Y unless followed by a vowel */ if (vowel(*(n + 1))) key << *n; break; case 'X': /* * KS */ if (*(n - 1) == '\0') key << 'S'; else key << "KS"; /* Insert K, then S */ break; case 'Z': /* * S */ key << 'S'; break; } } } } //***************************************************************************** // void Metaphone::addWord(char *word) // void Metaphone::addWord(char *word) { if (!dict) { dict = new Dictionary; } String key; generateKey(word, key); if (key.length() == 0) return; String *s = (String *) dict->Find(key); if (s) { // if (mystrcasestr(s->get(), word) != 0) (*s) << ' ' << word; } else { dict->Add(key, new String(word)); } }