iVar

suffix_tree.cpp
1 #include "iostream"
2 #include "algorithm"
3 #include "fstream"
4 #include "vector"
5
6 #include "suffix_tree.h"
7 #include "alignment.h"
8
9 suffix_node::suffix_node(int b, int *e, suffix_node *p, suffix_node *l){
10 this->children = new suffix_node*[MAX_CHAR];
11 for(unsigned int i = 0; i < MAX_CHAR;i++)
12 this->children[i] = 0;
13 this->begin = b;
14 this->end = e;
15 this->nchildren = 0;
16 this->parent = p;
17 this->suffix_link =l;
18 }
19
20 bool suffix_node::is_leaf_node(){
21 return (nchildren == 0);
22 }
23
24 bool suffix_node::contains_child(int ext){
25 return !(this->children[ext] == 0);
26 }
27
28 int suffix_node::get_length(){
29 if(this->end == 0)
30 return 0; // For root
31 return *(this->end) - this->begin + 1;
32 }
33
34 int suffix_node::get_depth(){
35 int ctr = 0;
36 suffix_node* n = this;
37 while(n->begin!=-1){
38 n = n->parent;
39 ctr++;
40 }
41 return ctr;
42 }
43
44 int get_hamming_distance(std::string s1, std::string s2, int k){
45 int n = 0;
46 for(unsigned int i = 0; i < s1.length(); i++){
47 if(s1[i] != s2[i]){
48 n++;
49 }
50 if(n > k)
51 return -1;
52 }
53 return n;
54 }
55
56 std::string suffix_node::get_longest_common_substring(std::string s1, std::string s2){
57 std::string str = s1+"#"+s2+"@";
58 std::string p="", tmp, longest_trvsl = "";
59 unsigned int max = 0, i;
60 suffix_node* node = this;
61 if(node->begin == -1)
62 p = "";
63 else{
64 tmp = node->get_path(str);
65 if(s1.find(p+tmp) != std::string::npos && s2.find(p+tmp) != std::string::npos)
66 p += tmp;
67 }
68 tmp = "";
69 for(i = 0; i < MAX_CHAR;i++){
70 if(node->children[i] == 0)
71 continue;
72 longest_trvsl = node->children[i]->get_longest_common_substring(s1, s2);
73 if(longest_trvsl.length() > max){
74 max = longest_trvsl.length();
75 tmp = longest_trvsl;
76 }
77 }
78 p += tmp;
79 return p;
80 }
81
82 std::string suffix_node::get_path(std::string s){
83 if(this->begin == -1)
84 return "R";
85 return s.substr(this->begin, *(this->end) - this->begin + 1);
86 }
87
88 void suffix_node::extend_path(int *e){
89 this->end = e;
90 }
91
92 suffix_node* suffix_node::add_child(int ext, int b, int *e, suffix_node* l){
93 suffix_node *n = new suffix_node(b, e, this, l);
94 this->children[ext] = n;
95 this->nchildren++;
96 return n;
97 }
98
99 void suffix_node::add_child(suffix_node* c, int ext){
100 this->children[ext] = c;
101 c->parent = this;
102 this->nchildren++;
103 }
104
105 suffix_node* suffix_node::get_child(int ext){
106 return this->children[ext];
107 }
108
109 bool suffix_node::contains_depth(int depth){
110 return this->get_depth() <= depth && depth <= (this->get_length() + this->get_depth());
111 }
112
113 void suffix_node::print(std::string s){
114 for(int i = 0; i < this->get_depth(); i++){
115 std::cout << " ";
116 }
117 std::string t = (this->begin == -1) ? "R" : " "+s.substr(this->begin, *(this->end) - this->begin + 1);
118 std::cout << t;
119 if(this->suffix_link != 0)
120 std::cout << " --- ( " << this->suffix_link->parent->get_path(s) << " " << this->suffix_link->get_path(s) << ")";
121 if(this->begin!=-1)
122 std::cout << " - " << this->parent->get_path(s);
123 std::cout << std::endl;
124 for(unsigned int i = 0; i<alphabet.length();i++){
125 if(this->children[i]!=0)
126 this->children[i]->print(s);
127 }
128 }
129
130 bool suffix_node::walk_next(int &beg, int &suffix_length){
131 suffix_node *node = this;
132 if(suffix_length >= node->get_length()){
133 beg += node->get_length();
134 suffix_length -= node->get_length();
135 return true;
136 }
137 return false;
138 }
139
140 suffix_node* build_suffix_tree(std::string s){
141 suffix_node *root = new suffix_node(-1,0,0,0);
142 root->suffix_link = root;
143 root->parent = root;
144 suffix_node *cur_node = root, *new_node = 0, *new_cur_node = 0;
145 int str_ind[MAX_SIZE], suffix_length = 0, *leaf_end= new int, suffix_count = 0, beg = -1, *end;
146 unsigned int i = 0, n_str_ind = 0;
147 for(i = 0; i < s.length();i++){
148 str_ind[i] = alphabet.find(s[i]);
149 n_str_ind++;
150 }
151 *leaf_end = 0;
152 // root->add_child(str_ind[0], 0, leaf_end, root);
153 for(i = 0; i < n_str_ind;i++){
154 *leaf_end = i; // Handle Extension Rule 1
155 suffix_count++;
156 new_node = 0;
157 while(suffix_count > 0){
158 if(suffix_length == 0)
159 beg = i;
160 if(cur_node->children[str_ind[beg]] == 0){ // Rule 2
161 cur_node->add_child(str_ind[beg], beg, leaf_end, 0); // Trick 3
162 if(new_node != 0){
163 new_node->suffix_link = cur_node;
164 new_node = 0; // No internal node created in Rule 2 here.
165 }
166 } else {
167 new_cur_node = cur_node->children[str_ind[beg]];
168 if(new_cur_node->walk_next(beg, suffix_length)){
169 cur_node = new_cur_node;
170 continue;
171 }
172 if(str_ind[new_cur_node->begin + suffix_length] == str_ind[i]){ // Rule 3
173 if(new_node != 0 && cur_node->end != 0){
174 new_node->suffix_link = cur_node;
175 new_node = 0; // No internal node created in Rule 2 here.
176 }
177 suffix_length++;
178 break;
179 }
180 // Rule 2 - New internal node created
181 suffix_node *new_int_node;
182 end = new int;
183 *end = new_cur_node->begin + suffix_length - 1;
184 //New internal node
185 new_int_node = cur_node->add_child(str_ind[beg], new_cur_node->begin, end, 0);
186 new_int_node->add_child(str_ind[i], i, leaf_end, 0);
187 new_cur_node->begin += suffix_length;
188 new_int_node->add_child(new_cur_node, str_ind[new_cur_node->begin]);
189 if(new_node != 0)
190 new_node->suffix_link = new_int_node;
191 new_node = new_int_node;
192 }
193 suffix_count--;
194 if(cur_node->end==0 && suffix_length > 0){
195 suffix_length--;
196 beg = i - suffix_count + 1;
197 } else if(cur_node->end!=0){
198 if(cur_node->suffix_link != 0){
199 cur_node = cur_node->suffix_link;
200 } else {
201 cur_node = cur_node->parent->suffix_link;
202 }
203 } else if(cur_node->get_length() == 1){
204 cur_node = root;
205 }
206 }
207 }
208 return root;
209 }
210
211 std::string get_reverse_complement(std::string rev_read){
212 char t;
213 for(unsigned int i = 0;i< rev_read.length();i++){
214 switch(rev_read[i]){
215 case 'A':
216 t = 'T';
217 break;
218 case 'G':
219 t='C';
220 break;
221 case 'C':
222 t='G';
223 break;
224 case 'T':
225 t='A';
226 break;
227 }
228 rev_read[i] = t;
229 }
230 std::reverse(rev_read.begin(), rev_read.end());
231 return rev_read;
232 }
233
234 std::vector<std::string> read_adapters_from_fasta(std::string p){
235 std::vector<std::string> adp;
236 std::ifstream fin(p);
237 std::string line;
238 while (std::getline(fin, line)){
239 if(line[0] == '>')
240 continue;
241 adp.push_back(line);
242 }
243 return adp;
244 }
245
246 std::string extend_till_mismatches(std::string cmn, std::string l, std::string adp){
247 if(cmn.length() < MIN_LENGTH){
248 return cmn;
249 }
250 int pos = adp.find(cmn);
251 int r_pos = l.find(cmn);
252 if(pos == 0) // Beginning of adapter match
253 return cmn;
254 int k = 0;
255 pos--;
256 r_pos--;
257 while(r_pos >= 0 && pos >= 0 && k <= MAX_MISMATCHES){
258 cmn = l[r_pos] + cmn;
259 if(l[r_pos]!=adp[pos])
260 k++;
261 r_pos--;
262 pos--;
263 }
264 return cmn;
265 }
266
267 int trim_adapter(std::string f1, std::string f2, std::string adp_path, std::string p){
268 std::string l1, l2, l1_rc, l2_rc, s, cmn, trmd_read;
269 int *t = new int[2], beg;
270 unsigned int pos;
271 std::ifstream ff1(f1), ff2, pf(p);
272 std::ofstream out(p+".trimmed.fastq");
273 std::vector<std::string>::iterator it;
274 suffix_node *root = (suffix_node*) malloc(sizeof(suffix_node));
275 std::vector<std::string> adp = read_adapters_from_fasta(adp_path);
276 int i = -1, n = 0, adp_pos;
277 if(!f2.empty()){
278 ff2.open(f2);
279 while (std::getline(ff1, l1) && std::getline(ff2, l2)){
280 i++;
281 if((i - 1)%4 != 0)
282 continue;
283 }
284 } else {
285 while (std::getline(ff1, l1)){
286 i++;
287 if((i - 1)%4 != 0){
288 out << l1 << std::endl;
289 continue;
290 }
291 beg = 0;
292 pos = l1.length();
293 trmd_read = l1;
294 for(it = adp.begin(); it != adp.end(); ++it) {
295 s = l1 + "#" + *it + "@";
296 root = build_suffix_tree(s);
297 cmn = root->get_longest_common_substring(l1, *it);
298 cmn = extend_till_mismatches(cmn, l1, *it);
299 if(cmn.empty()){
300 l1_rc = get_reverse_complement(l1);
301 s = l1_rc + "#" + *it + "@";
302 root = build_suffix_tree(s);
303 cmn = root->get_longest_common_substring(l1_rc, *it);
304 cmn = extend_till_mismatches(cmn, l1_rc, *it);
305 pos = l1_rc.find(cmn);
306 beg = l1_rc.length() - pos;
307 adp_pos = (*it).find(cmn);
308 } else {
309 beg = 0;
310 pos = l1.find(cmn);
311 adp_pos = (*it).find(cmn);
312 }
313 if(cmn.length() >= MIN_LENGTH && adp_pos != 0){
314 beg = 0;
315 pos = l1.length();
316 t = align_seqs(l1, *it);
317 if(*t != -1){
318 beg = 0;
319 pos = *(t+1);
320 } else {
321 std::cout << "Reverse!" << std::endl;
322 l1_rc = get_reverse_complement(l1);
323 t = align_seqs(l1_rc, *it);
324 if(*t != -1){
325 pos = l1.length() - *(t+1);
326 beg = *(t+1);
327 }
328 }
329 }
330 std::cout << beg << " " << pos << std::endl;
331 if(beg != 0 || pos != l1.length()){
332 trmd_read = l1.substr(beg, pos);
333 n++;
334 break;
335 }
336 }
337 out << trmd_read << std::endl;
338 }
339 }
340 std::cout << "Number of Adapter Trimmed: :" << n << std::endl;
341 delete root;
342 delete[] t;
343 ff1.close();
344 ff2.close();
345 pf.close();
346 return 0;
347 }
suffix_node
Definition: suffix_tree.h:14