Ejemplo n.º 1
0
        private void LoadStopWords(IHostEnvironment env, IChannel ch, ArgumentsBase loaderArgs, out NormStr.Pool stopWordsMap)
        {
            Contracts.AssertValue(env);
            env.AssertValue(ch);
            ch.AssertValue(loaderArgs);

            if ((!string.IsNullOrEmpty(loaderArgs.Stopwords) || Utils.Size(loaderArgs.Stopword) > 0) &&
                (!string.IsNullOrWhiteSpace(loaderArgs.DataFile) || loaderArgs.Loader.IsGood() ||
                 !string.IsNullOrWhiteSpace(loaderArgs.StopwordsColumn)))
            {
                ch.Warning("Explicit stopwords list specified. Data file arguments will be ignored");
            }

            var src = default(DvText);

            stopWordsMap = new NormStr.Pool();
            var buffer = new StringBuilder();

            var stopwords = new DvText(loaderArgs.Stopwords);

            stopwords = stopwords.Trim();
            if (stopwords.HasChars)
            {
                bool warnEmpty = true;
                for (bool more = true; more;)
                {
                    DvText stopword;
                    more     = stopwords.SplitOne(',', out stopword, out stopwords);
                    stopword = stopword.Trim();
                    if (stopword.HasChars)
                    {
                        buffer.Clear();
                        stopword.AddLowerCaseToStringBuilder(buffer);
                        stopWordsMap.Add(buffer);
                    }
                    else if (warnEmpty)
                    {
                        ch.Warning("Empty strings ignored in 'stopwords' specification");
                        warnEmpty = false;
                    }
                }
                ch.CheckUserArg(stopWordsMap.Count > 0, nameof(Arguments.Stopwords), "stopwords is empty");
            }
            else if (Utils.Size(loaderArgs.Stopword) > 0)
            {
                bool warnEmpty = true;
                foreach (string word in loaderArgs.Stopword)
                {
                    var stopword = new DvText(word);
                    stopword = stopword.Trim();
                    if (stopword.HasChars)
                    {
                        buffer.Clear();
                        stopword.AddLowerCaseToStringBuilder(buffer);
                        stopWordsMap.Add(buffer);
                    }
                    else if (warnEmpty)
                    {
                        ch.Warning("Empty strings ignored in 'stopword' specification");
                        warnEmpty = false;
                    }
                }
            }
            else
            {
                string srcCol = loaderArgs.StopwordsColumn;
                var    loader = LoadStopwords(env, ch, loaderArgs.DataFile, loaderArgs.Loader, ref srcCol);
                int    colSrc;
                if (!loader.Schema.TryGetColumnIndex(srcCol, out colSrc))
                {
                    throw ch.ExceptUserArg(nameof(Arguments.StopwordsColumn), "Unknown column '{0}'", srcCol);
                }
                var typeSrc = loader.Schema.GetColumnType(colSrc);
                ch.CheckUserArg(typeSrc.IsText, nameof(Arguments.StopwordsColumn), "Must be a scalar text column");

                // Accumulate the stopwords.
                using (var cursor = loader.GetRowCursor(col => col == colSrc))
                {
                    bool warnEmpty = true;
                    var  getter    = cursor.GetGetter <DvText>(colSrc);
                    while (cursor.MoveNext())
                    {
                        getter(ref src);
                        if (src.HasChars)
                        {
                            buffer.Clear();
                            src.AddLowerCaseToStringBuilder(buffer);
                            stopWordsMap.Add(buffer);
                        }
                        else if (warnEmpty)
                        {
                            ch.Warning("Empty rows ignored in data file");
                            warnEmpty = false;
                        }
                    }
                }
                ch.CheckUserArg(stopWordsMap.Count > 0, nameof(Arguments.DataFile), "dataFile is empty");
            }
        }