/**
* Returns the most similar {@link Term} for the term represented by the specified sdr
*
* @param sdr sparse int array
* @return
*/
Term getClosestTerm(int[] sdr) {
Fingerprint fp = new Fingerprint(sdr);
try {
List<Term> terms = getSimilarTerms(fp);
// Retrieve terms from cache if present
for (int i = 0; i < terms.size(); i++) {
if (cache.containsKey(terms.get(i).getTerm())) {
terms.set(i, cache.get(terms.get(i).getTerm()));
}
}
Term retVal = null;
if (terms != null && terms.size() > 0) {
retVal = terms.get(0);
if (checkTerm(retVal.getTerm(), retVal, true)) {
return retVal;
}
// Cache fall through incomplete term for next time
cache.put(retVal.getTerm(), retVal = getTerms(retVal.getTerm(), true).get(0));
return retVal;
}
} catch (Exception e) {
LOGGER.debug("Problem using Expressions API");
e.printStackTrace();
}
return null;
}
/**
* Feeds the {@link Network with the final phrase consisting of the first
* two words of the final question "fox, eats, ...".
*
* @param network the current {@link Network} object
* @param it an {@link Iterator} over the input source file lines
* @return
*/
Term feedQuestion(Network network, String[] phrase) {
for (int i = 0; i < 2; i++) {
int[] sdr = getFingerprintSDR(phrase[i]);
network.compute(sdr);
}
Layer<?> layer = network.lookup("Region 1").lookup("Layer 2/3");
Set<Cell> predictiveCells = layer.getPredictiveCells();
int[] prediction =
SDR.cellsAsColumnIndices(predictiveCells, layer.getConnections().getCellsPerColumn());
Term term = getClosestTerm(prediction);
cache.put(term.getTerm(), term);
return term;
}
/**
* Called by {@link #checkCache(boolean, boolean)} for every line in the cache file to validate
* the contents of the specified {@link Term}
*
* @param key
* @param t
* @param print
* @return
*/
boolean checkTerm(String key, Term t, boolean print) {
Fingerprint fp = t.getFingerprint();
if (fp == null) {
if (print) {
LOGGER.debug("\tkey: " + key + ", missing fingerprint");
}
return false;
}
int[] pos = fp.getPositions();
if (pos == null) {
if (print) {
LOGGER.debug("\tkey: " + key + ", has null positions");
}
return false;
}
if (pos.length < 1) {
if (print) {
LOGGER.debug("\tkey: " + key + ", had empty positions");
}
return false;
}
int sdrLen = pos.length;
if (print) {
LOGGER.debug("\tkey: " + key + ", term len: " + sdrLen);
}
return true;
}
/**
* Returns a {@link Fingerprint} for the specified term.
*
* @param term
* @return
*/
Fingerprint getFingerprint(String term) {
try {
Term t = cache.get(term) == null ? getTerms(term, true).get(0) : cache.get(term);
if (!checkTerm(t.getTerm(), t, true)) {
throw new IllegalStateException("Checkterm failed: " + t.getTerm());
}
cache.put(t.getTerm(), t);
return t.getFingerprint();
} catch (Exception e) {
LOGGER.debug("Problem retrieving fingerprint for term: " + term);
}
return null;
}
/**
* Loads the fingerprint cache file into memory if it exists. If it does not exist, this method
* creates the file; however it won't be written to until the demo is finished processing, at
* which point {@link #writeCache()} is called to store the cache file.
*/
void loadCache() {
if (cache == null) {
cache = new HashMap<>();
}
String json = null;
try {
StringBuilder sb = new StringBuilder();
getCacheStream()
.forEach(
l -> {
sb.append(l);
});
json = sb.toString();
} catch (IOException e) {
e.printStackTrace();
}
if (json.isEmpty()) {
LOGGER.debug("Term cache is empty.");
return;
}
ObjectMapper mapper = new ObjectMapper();
List<Term> terms = null;
try {
terms = Arrays.asList(mapper.readValue(json, Term[].class));
if (terms == null) {
LOGGER.debug("Term cache is empty or malformed.");
}
} catch (IOException e) {
e.printStackTrace();
}
for (Term t : terms) {
cache.put(t.getTerm(), t);
}
checkCache(true, true);
}
/**
* Writes the fingerprint cache file to disk. This takes place at the end of the demo's
* processing.
*/
void writeCache() {
File f = getCacheFile();
try (PrintWriter pw = new PrintWriter(new FileWriter(f))) {
StringBuilder builderStr = new StringBuilder();
int i = 0;
for (Iterator<Term> it = cache.values().iterator(); it.hasNext(); i++) {
Term t = it.next();
String termStr = Term.toJson(t);
if (i > 0) {
termStr = termStr.substring(1).trim();
}
termStr = termStr.substring(0, termStr.length() - 1).trim();
builderStr.append(termStr).append(",");
}
builderStr.setLength(builderStr.length() - 1);
builderStr.append(" ]");
pw.println(builderStr.toString());
pw.flush();
} catch (IOException e) {
e.printStackTrace();
}
}