1 | #region License Information
|
---|
2 | /* HeuristicLab
|
---|
3 | * Copyright (C) 2002-2018 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
|
---|
4 | *
|
---|
5 | * This file is part of HeuristicLab.
|
---|
6 | *
|
---|
7 | * HeuristicLab is free software: you can redistribute it and/or modify
|
---|
8 | * it under the terms of the GNU General Public License as published by
|
---|
9 | * the Free Software Foundation, either version 3 of the License, or
|
---|
10 | * (at your option) any later version.
|
---|
11 | *
|
---|
12 | * HeuristicLab is distributed in the hope that it will be useful,
|
---|
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
---|
15 | * GNU General Public License for more details.
|
---|
16 | *
|
---|
17 | * You should have received a copy of the GNU General Public License
|
---|
18 | * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
|
---|
19 | */
|
---|
20 | #endregion
|
---|
21 |
|
---|
22 |
|
---|
23 | using System;
|
---|
24 | using System.Collections;
|
---|
25 | using System.Collections.Generic;
|
---|
26 | using System.Diagnostics.Contracts;
|
---|
27 | using System.Globalization;
|
---|
28 | using System.IO;
|
---|
29 | using System.Linq;
|
---|
30 | using System.Text;
|
---|
31 |
|
---|
32 | namespace HeuristicLab.Problems.Instances.DataAnalysis {
|
---|
33 | public class TableFileParser : Progress<long> { // reports the number of bytes read
|
---|
34 | private const int BUFFER_SIZE = 65536;
|
---|
35 | // char used to symbolize whitespaces (no missing values can be handled with whitespaces)
|
---|
36 | private const char WHITESPACECHAR = (char)0;
|
---|
37 | private static readonly char[] POSSIBLE_SEPARATORS = new char[] { ',', ';', '\t', WHITESPACECHAR };
|
---|
38 | private Tokenizer tokenizer;
|
---|
39 | private int estimatedNumberOfLines = 200; // initial capacity for columns, will be set automatically when data is read from a file
|
---|
40 |
|
---|
41 |
|
---|
42 | private Encoding encoding = Encoding.Default;
|
---|
43 |
|
---|
44 | public Encoding Encoding {
|
---|
45 | get { return encoding; }
|
---|
46 | set {
|
---|
47 | if (value == null) throw new ArgumentNullException("Encoding");
|
---|
48 | encoding = value;
|
---|
49 | }
|
---|
50 | }
|
---|
51 |
|
---|
52 |
|
---|
53 | private int rows;
|
---|
54 | public int Rows {
|
---|
55 | get { return rows; }
|
---|
56 | set { rows = value; }
|
---|
57 | }
|
---|
58 |
|
---|
59 | private int columns;
|
---|
60 | public int Columns {
|
---|
61 | get { return columns; }
|
---|
62 | set { columns = value; }
|
---|
63 | }
|
---|
64 |
|
---|
65 | private List<IList> values;
|
---|
66 | public List<IList> Values {
|
---|
67 | get {
|
---|
68 | return values;
|
---|
69 | }
|
---|
70 | }
|
---|
71 |
|
---|
72 | private List<string> variableNames;
|
---|
73 | public IEnumerable<string> VariableNames {
|
---|
74 | get {
|
---|
75 | if (variableNames.Count > 0) return variableNames;
|
---|
76 | else {
|
---|
77 | string[] names = new string[columns];
|
---|
78 | for (int i = 0; i < names.Length; i++) {
|
---|
79 | names[i] = "X" + i.ToString("000");
|
---|
80 | }
|
---|
81 | return names;
|
---|
82 | }
|
---|
83 | }
|
---|
84 | }
|
---|
85 |
|
---|
86 | public TableFileParser() {
|
---|
87 | variableNames = new List<string>();
|
---|
88 | }
|
---|
89 |
|
---|
90 | public bool AreColumnNamesInFirstLine(string fileName) {
|
---|
91 | NumberFormatInfo numberFormat;
|
---|
92 | DateTimeFormatInfo dateTimeFormatInfo;
|
---|
93 | char separator;
|
---|
94 | DetermineFileFormat(fileName, out numberFormat, out dateTimeFormatInfo, out separator);
|
---|
95 | using (var stream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)) {
|
---|
96 | return AreColumnNamesInFirstLine(stream, numberFormat, dateTimeFormatInfo, separator);
|
---|
97 | }
|
---|
98 | }
|
---|
99 |
|
---|
100 | public bool AreColumnNamesInFirstLine(Stream stream) {
|
---|
101 | NumberFormatInfo numberFormat = NumberFormatInfo.InvariantInfo;
|
---|
102 | DateTimeFormatInfo dateTimeFormatInfo = DateTimeFormatInfo.InvariantInfo;
|
---|
103 | char separator = ',';
|
---|
104 | return AreColumnNamesInFirstLine(stream, numberFormat, dateTimeFormatInfo, separator);
|
---|
105 | }
|
---|
106 |
|
---|
107 | public bool AreColumnNamesInFirstLine(string fileName, NumberFormatInfo numberFormat,
|
---|
108 | DateTimeFormatInfo dateTimeFormatInfo, char separator) {
|
---|
109 | using (var stream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)) {
|
---|
110 | return AreColumnNamesInFirstLine(stream, numberFormat, dateTimeFormatInfo, separator);
|
---|
111 | }
|
---|
112 | }
|
---|
113 |
|
---|
114 | public bool AreColumnNamesInFirstLine(Stream stream, NumberFormatInfo numberFormat,
|
---|
115 | DateTimeFormatInfo dateTimeFormatInfo, char separator) {
|
---|
116 | using (StreamReader reader = new StreamReader(stream, Encoding)) {
|
---|
117 | tokenizer = new Tokenizer(reader, numberFormat, dateTimeFormatInfo, separator);
|
---|
118 | return (tokenizer.PeekType() != TokenTypeEnum.Double);
|
---|
119 | }
|
---|
120 | }
|
---|
121 |
|
---|
122 | /// <summary>
|
---|
123 | /// Parses a file and determines the format first
|
---|
124 | /// </summary>
|
---|
125 | /// <param name="fileName">file which is parsed</param>
|
---|
126 | /// <param name="columnNamesInFirstLine"></param>
|
---|
127 | public void Parse(string fileName, bool columnNamesInFirstLine, int lineLimit = -1) {
|
---|
128 | NumberFormatInfo numberFormat;
|
---|
129 | DateTimeFormatInfo dateTimeFormatInfo;
|
---|
130 | char separator;
|
---|
131 | DetermineFileFormat(fileName, out numberFormat, out dateTimeFormatInfo, out separator);
|
---|
132 | EstimateNumberOfLines(fileName);
|
---|
133 | Parse(new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite), numberFormat, dateTimeFormatInfo, separator, columnNamesInFirstLine, lineLimit);
|
---|
134 | }
|
---|
135 |
|
---|
136 | /// <summary>
|
---|
137 | /// Parses a file with the given formats
|
---|
138 | /// </summary>
|
---|
139 | /// <param name="fileName">file which is parsed</param>
|
---|
140 | /// <param name="numberFormat">Format of numbers</param>
|
---|
141 | /// <param name="dateTimeFormatInfo">Format of datetime</param>
|
---|
142 | /// <param name="separator">defines the separator</param>
|
---|
143 | /// <param name="columnNamesInFirstLine"></param>
|
---|
144 | public void Parse(string fileName, NumberFormatInfo numberFormat, DateTimeFormatInfo dateTimeFormatInfo, char separator, bool columnNamesInFirstLine, int lineLimit = -1) {
|
---|
145 | EstimateNumberOfLines(fileName);
|
---|
146 | using (var stream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)) {
|
---|
147 | Parse(stream, numberFormat, dateTimeFormatInfo, separator, columnNamesInFirstLine, lineLimit);
|
---|
148 | }
|
---|
149 | }
|
---|
150 |
|
---|
151 | // determines the number of newline characters in the first 64KB to guess the number of rows for a file
|
---|
152 | private void EstimateNumberOfLines(string fileName) {
|
---|
153 | var len = new System.IO.FileInfo(fileName).Length;
|
---|
154 | var buf = new char[1024 * 1024];
|
---|
155 | using (var reader = new StreamReader(fileName, Encoding)) {
|
---|
156 | reader.ReadBlock(buf, 0, buf.Length);
|
---|
157 | }
|
---|
158 | int numNewLine = 0;
|
---|
159 | int charsInCurrentLine = 0, charsInFirstLine = 0; // the first line (names) and the last line (incomplete) are not representative
|
---|
160 | foreach (var ch in buf) {
|
---|
161 | charsInCurrentLine++;
|
---|
162 | if (ch == '\n') {
|
---|
163 | if (numNewLine == 0) charsInFirstLine = charsInCurrentLine; // store the number of chars in the first line
|
---|
164 | charsInCurrentLine = 0;
|
---|
165 | numNewLine++;
|
---|
166 | }
|
---|
167 | }
|
---|
168 | if (numNewLine <= 1) {
|
---|
169 | // fail -> keep the default setting
|
---|
170 | return;
|
---|
171 | } else {
|
---|
172 | double charsPerLineFactor = (buf.Length - charsInFirstLine - charsInCurrentLine) / ((double)numNewLine - 1);
|
---|
173 | double estimatedLines = len / charsPerLineFactor;
|
---|
174 | estimatedNumberOfLines = (int)Math.Round(estimatedLines * 1.1); // pessimistic allocation of 110% to make sure that the list is very likely large enough
|
---|
175 | }
|
---|
176 | }
|
---|
177 |
|
---|
178 | /// <summary>
|
---|
179 | /// Takes a Stream and parses it with default format. NumberFormatInfo.InvariantInfo, DateTimeFormatInfo.InvariantInfo and separator = ','
|
---|
180 | /// </summary>
|
---|
181 | /// <param name="stream">stream which is parsed</param>
|
---|
182 | /// <param name="columnNamesInFirstLine"></param>
|
---|
183 | public void Parse(Stream stream, bool columnNamesInFirstLine, int lineLimit = -1) {
|
---|
184 | NumberFormatInfo numberFormat = NumberFormatInfo.InvariantInfo;
|
---|
185 | DateTimeFormatInfo dateTimeFormatInfo = DateTimeFormatInfo.InvariantInfo;
|
---|
186 | char separator = ',';
|
---|
187 | Parse(stream, numberFormat, dateTimeFormatInfo, separator, columnNamesInFirstLine, lineLimit);
|
---|
188 | }
|
---|
189 |
|
---|
190 | /// <summary>
|
---|
191 | /// Parses a stream with the given formats.
|
---|
192 | /// </summary>
|
---|
193 | /// <param name="stream">Stream which is parsed</param>
|
---|
194 | /// <param name="numberFormat">Format of numbers</param>
|
---|
195 | /// <param name="dateTimeFormatInfo">Format of datetime</param>
|
---|
196 | /// <param name="separator">defines the separator</param>
|
---|
197 | /// <param name="columnNamesInFirstLine"></param>
|
---|
198 | public void Parse(Stream stream, NumberFormatInfo numberFormat, DateTimeFormatInfo dateTimeFormatInfo, char separator, bool columnNamesInFirstLine, int lineLimit = -1) {
|
---|
199 | if (lineLimit > 0) estimatedNumberOfLines = lineLimit;
|
---|
200 |
|
---|
201 | using (var reader = new StreamReader(stream)) {
|
---|
202 | tokenizer = new Tokenizer(reader, numberFormat, dateTimeFormatInfo, separator);
|
---|
203 | var strValues = new List<List<string>>();
|
---|
204 | values = new List<IList>();
|
---|
205 | Prepare(columnNamesInFirstLine, strValues);
|
---|
206 |
|
---|
207 | int nLinesParsed = 0;
|
---|
208 | int colIdx = 0;
|
---|
209 | while (tokenizer.HasNext() && (lineLimit < 0 || nLinesParsed < lineLimit)) {
|
---|
210 | if (tokenizer.PeekType() == TokenTypeEnum.NewLine) {
|
---|
211 | tokenizer.Skip();
|
---|
212 |
|
---|
213 | // all rows have to have the same number of values
|
---|
214 | // the first row defines how many elements are needed
|
---|
215 | if (colIdx > 0 && values.Count != colIdx) {
|
---|
216 | // read at least one value in the row (support for skipping empty lines)
|
---|
217 | Error("The first row of the dataset has " + values.Count + " columns." + Environment.NewLine +
|
---|
218 | "Line " + tokenizer.CurrentLineNumber + " has " + colIdx + " columns.", "",
|
---|
219 | tokenizer.CurrentLineNumber);
|
---|
220 | }
|
---|
221 | OnReport(tokenizer.BytesRead);
|
---|
222 |
|
---|
223 | nLinesParsed++;
|
---|
224 | colIdx = 0;
|
---|
225 | } else {
|
---|
226 | // read one value
|
---|
227 | TokenTypeEnum type;
|
---|
228 | string strVal;
|
---|
229 | double dblVal;
|
---|
230 | DateTime dateTimeVal;
|
---|
231 | tokenizer.Next(out type, out strVal, out dblVal, out dateTimeVal);
|
---|
232 |
|
---|
233 | if (colIdx == values.Count) {
|
---|
234 | Error("The first row of the dataset has " + values.Count + " columns." + Environment.NewLine +
|
---|
235 | "Line " + tokenizer.CurrentLineNumber + " has more columns.", "",
|
---|
236 | tokenizer.CurrentLineNumber);
|
---|
237 | }
|
---|
238 | if (!IsColumnTypeCompatible(values[colIdx], type)) {
|
---|
239 | values[colIdx] = strValues[colIdx];
|
---|
240 | }
|
---|
241 |
|
---|
242 | // add the value to the column
|
---|
243 | AddValue(type, values[colIdx], strVal, dblVal, dateTimeVal);
|
---|
244 | if (!(values[colIdx] is List<string>)) { // optimization: don't store the string values in another list if the column is list<string>
|
---|
245 | strValues[colIdx].Add(strVal);
|
---|
246 | }
|
---|
247 | colIdx++;
|
---|
248 | }
|
---|
249 | }
|
---|
250 | }
|
---|
251 |
|
---|
252 | if (!values.Any() || values.First().Count == 0)
|
---|
253 | Error("Couldn't parse data values. Probably because of incorrect number format " +
|
---|
254 | "(the parser expects english number format with a '.' as decimal separator).", "", tokenizer.CurrentLineNumber);
|
---|
255 |
|
---|
256 | this.rows = values.First().Count;
|
---|
257 | this.columns = values.Count;
|
---|
258 |
|
---|
259 | // replace lists with undefined type (object) with double-lists
|
---|
260 | for (int i = 0; i < values.Count; i++) {
|
---|
261 | if (values[i] is List<object>) {
|
---|
262 | values[i] = Enumerable.Repeat(double.NaN, rows).ToList();
|
---|
263 | }
|
---|
264 | }
|
---|
265 |
|
---|
266 | // after everything has been parsed make sure the lists are as compact as possible
|
---|
267 | foreach (var l in values) {
|
---|
268 | var dblList = l as List<double>;
|
---|
269 | var byteList = l as List<byte>;
|
---|
270 | var dateList = l as List<DateTime>;
|
---|
271 | var stringList = l as List<string>;
|
---|
272 | var objList = l as List<object>;
|
---|
273 | if (dblList != null) dblList.TrimExcess();
|
---|
274 | if (byteList != null) byteList.TrimExcess();
|
---|
275 | if (dateList != null) dateList.TrimExcess();
|
---|
276 | if (stringList != null) stringList.TrimExcess();
|
---|
277 | if (objList != null) objList.TrimExcess();
|
---|
278 | }
|
---|
279 |
|
---|
280 | // for large files we created a lot of memory pressure, cannot hurt to run GC.Collect here (TableFileParser is called seldomly on user interaction)
|
---|
281 | GC.Collect(2, GCCollectionMode.Forced);
|
---|
282 | }
|
---|
283 |
|
---|
284 | private void Prepare(bool columnNamesInFirstLine, List<List<string>> strValues) {
|
---|
285 | if (columnNamesInFirstLine) {
|
---|
286 | ParseVariableNames();
|
---|
287 | if (!tokenizer.HasNext())
|
---|
288 | Error(
|
---|
289 | "Couldn't parse data values. Probably because of incorrect number format (the parser expects english number format with a '.' as decimal separator).",
|
---|
290 | "", tokenizer.CurrentLineNumber);
|
---|
291 | }
|
---|
292 | // read first line to determine types and allocate specific lists
|
---|
293 | // read values... start in first row
|
---|
294 | int colIdx = 0;
|
---|
295 | while (tokenizer.PeekType() != TokenTypeEnum.NewLine) {
|
---|
296 | // read one value
|
---|
297 | TokenTypeEnum type; string strVal; double dblVal; DateTime dateTimeVal;
|
---|
298 | tokenizer.Next(out type, out strVal, out dblVal, out dateTimeVal);
|
---|
299 |
|
---|
300 | // initialize column
|
---|
301 | values.Add(CreateList(type, estimatedNumberOfLines));
|
---|
302 | if (type == TokenTypeEnum.String)
|
---|
303 | strValues.Add(new List<string>(0)); // optimization: don't store the string values in another list if the column is list<string>
|
---|
304 | else
|
---|
305 | strValues.Add(new List<string>(estimatedNumberOfLines));
|
---|
306 |
|
---|
307 | AddValue(type, values[colIdx], strVal, dblVal, dateTimeVal);
|
---|
308 | if (type != TokenTypeEnum.String)
|
---|
309 | strValues[colIdx].Add(strVal);
|
---|
310 | colIdx++;
|
---|
311 | }
|
---|
312 | tokenizer.Skip(); // skip newline
|
---|
313 | }
|
---|
314 |
|
---|
315 | #region type-dependent dispatch
|
---|
316 | private bool IsColumnTypeCompatible(IList list, TokenTypeEnum tokenType) {
|
---|
317 | return (list is List<object>) || // unknown lists are compatible to everything (potential conversion)
|
---|
318 | (list is List<string>) || // all tokens can be added to a string list
|
---|
319 | (tokenType == TokenTypeEnum.Missing) || // empty entries are allowed in all columns
|
---|
320 | (tokenType == TokenTypeEnum.Double && list is List<double>) ||
|
---|
321 | (tokenType == TokenTypeEnum.DateTime && list is List<DateTime>);
|
---|
322 | }
|
---|
323 |
|
---|
324 | // all columns are converted to string columns when we find an non-empty value that has incorrect type
|
---|
325 | private IList ConvertToStringColumn(IList list) {
|
---|
326 | var dblL = list as List<double>;
|
---|
327 | if (dblL != null) {
|
---|
328 | var l = new List<string>(dblL.Capacity);
|
---|
329 | l.AddRange(dblL.Select(dbl => dbl.ToString()));
|
---|
330 | return l;
|
---|
331 | }
|
---|
332 |
|
---|
333 | var dtL = list as List<DateTime>;
|
---|
334 | if (dtL != null) {
|
---|
335 | var l = new List<string>(dtL.Capacity);
|
---|
336 | l.AddRange(dtL.Select(dbl => dbl.ToString()));
|
---|
337 | return l;
|
---|
338 | }
|
---|
339 |
|
---|
340 | if (list is List<string>) return list;
|
---|
341 |
|
---|
342 | throw new InvalidProgramException(string.Format("Cannot convert column of type {0} to string column", list.GetType()));
|
---|
343 | }
|
---|
344 |
|
---|
345 | private void AddValue(TokenTypeEnum type, IList list, string strVal, double dblVal, DateTime dateTimeVal) {
|
---|
346 | // Add value if list has a defined type
|
---|
347 | var dblList = list as List<double>;
|
---|
348 | if (dblList != null) {
|
---|
349 | AddValue(type, dblList, dblVal);
|
---|
350 | return;
|
---|
351 | }
|
---|
352 | var strList = list as List<string>;
|
---|
353 | if (strList != null) {
|
---|
354 | AddValue(type, strList, strVal);
|
---|
355 | return;
|
---|
356 | }
|
---|
357 | var dtList = list as List<DateTime>;
|
---|
358 | if (dtList != null) {
|
---|
359 | AddValue(type, dtList, dateTimeVal);
|
---|
360 | return;
|
---|
361 | }
|
---|
362 |
|
---|
363 | // Undefined list-type
|
---|
364 | if (type == TokenTypeEnum.Missing) {
|
---|
365 | // add null to track number of missing values
|
---|
366 | list.Add(null);
|
---|
367 | } else { // first non-missing value for undefined list-type
|
---|
368 | var newList = ConvertList(type, list, estimatedNumberOfLines);
|
---|
369 | // replace list
|
---|
370 | var idx = values.IndexOf(list);
|
---|
371 | values[idx] = newList;
|
---|
372 | // recursively call AddValue
|
---|
373 | AddValue(type, newList, strVal, dblVal, dateTimeVal);
|
---|
374 | }
|
---|
375 | }
|
---|
376 |
|
---|
377 | private static void AddValue(TokenTypeEnum type, List<double> list, double dblVal) {
|
---|
378 | Contract.Assert(type == TokenTypeEnum.Missing || type == TokenTypeEnum.Double);
|
---|
379 | list.Add(type == TokenTypeEnum.Missing ? double.NaN : dblVal);
|
---|
380 | }
|
---|
381 |
|
---|
382 | private static void AddValue(TokenTypeEnum type, List<string> list, string strVal) {
|
---|
383 | // assumes that strVal is always set to the original token read from the input file
|
---|
384 | list.Add(type == TokenTypeEnum.Missing ? string.Empty : strVal);
|
---|
385 | }
|
---|
386 |
|
---|
387 | private static void AddValue(TokenTypeEnum type, List<DateTime> list, DateTime dtVal) {
|
---|
388 | Contract.Assert(type == TokenTypeEnum.Missing || type == TokenTypeEnum.DateTime);
|
---|
389 | list.Add(type == TokenTypeEnum.Missing ? DateTime.MinValue : dtVal);
|
---|
390 | }
|
---|
391 |
|
---|
392 | private static IList CreateList(TokenTypeEnum type, int estimatedNumberOfLines) {
|
---|
393 | switch (type) {
|
---|
394 | case TokenTypeEnum.String:
|
---|
395 | return new List<string>(estimatedNumberOfLines);
|
---|
396 | case TokenTypeEnum.Double:
|
---|
397 | return new List<double>(estimatedNumberOfLines);
|
---|
398 | case TokenTypeEnum.DateTime:
|
---|
399 | return new List<DateTime>(estimatedNumberOfLines);
|
---|
400 | case TokenTypeEnum.Missing: // List<object> represent list of unknown type
|
---|
401 | return new List<object>(estimatedNumberOfLines);
|
---|
402 | default:
|
---|
403 | throw new InvalidOperationException();
|
---|
404 | }
|
---|
405 | }
|
---|
406 |
|
---|
407 | private static IList ConvertList(TokenTypeEnum type, IList list, int estimatedNumberOfLines) {
|
---|
408 | var newList = CreateList(type, estimatedNumberOfLines);
|
---|
409 | object missingValue = GetMissingValue(type);
|
---|
410 | for (int i = 0; i < list.Count; i++)
|
---|
411 | newList.Add(missingValue);
|
---|
412 | return newList;
|
---|
413 | }
|
---|
414 | private static object GetMissingValue(TokenTypeEnum type) {
|
---|
415 | switch (type) {
|
---|
416 | case TokenTypeEnum.String: return string.Empty;
|
---|
417 | case TokenTypeEnum.Double: return double.NaN;
|
---|
418 | case TokenTypeEnum.DateTime: return DateTime.MinValue;
|
---|
419 | default: throw new ArgumentOutOfRangeException("type", type, "No missing value defined");
|
---|
420 | }
|
---|
421 | }
|
---|
422 | #endregion
|
---|
423 |
|
---|
424 | public static void DetermineFileFormat(string path, out NumberFormatInfo numberFormat, out DateTimeFormatInfo dateTimeFormatInfo, out char separator) {
|
---|
425 | DetermineFileFormat(new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite), out numberFormat, out dateTimeFormatInfo, out separator);
|
---|
426 | }
|
---|
427 |
|
---|
428 | public static void DetermineFileFormat(Stream stream, out NumberFormatInfo numberFormat, out DateTimeFormatInfo dateTimeFormatInfo, out char separator) {
|
---|
429 | using (StreamReader reader = new StreamReader(stream)) {
|
---|
430 | // skip first line
|
---|
431 | reader.ReadLine();
|
---|
432 | // read a block
|
---|
433 | char[] buffer = new char[BUFFER_SIZE];
|
---|
434 | int charsRead = reader.ReadBlock(buffer, 0, BUFFER_SIZE);
|
---|
435 | // count frequency of special characters
|
---|
436 | Dictionary<char, int> charCounts = buffer.Take(charsRead)
|
---|
437 | .GroupBy(c => c)
|
---|
438 | .ToDictionary(g => g.Key, g => g.Count());
|
---|
439 |
|
---|
440 | // depending on the characters occuring in the block
|
---|
441 | // we distinghish a number of different cases based on the the following rules:
|
---|
442 | // many points => it must be English number format, the other frequently occuring char is the separator
|
---|
443 | // no points but many commas => this is the problematic case. Either German format (real numbers) or English format (only integer numbers) with ',' as separator
|
---|
444 | // => check the line in more detail:
|
---|
445 | // English: 0, 0, 0, 0
|
---|
446 | // German: 0,0 0,0 0,0 ...
|
---|
447 | // => if commas are followed by space => English format
|
---|
448 | // no points no commas => English format (only integer numbers) use the other frequently occuring char as separator
|
---|
449 | // in all cases only treat ' ' as separator if no other separator is possible (spaces can also occur additionally to separators)
|
---|
450 | if (OccurrencesOf(charCounts, '.') > 10) {
|
---|
451 | numberFormat = NumberFormatInfo.InvariantInfo;
|
---|
452 | dateTimeFormatInfo = DateTimeFormatInfo.InvariantInfo;
|
---|
453 | separator = POSSIBLE_SEPARATORS
|
---|
454 | .Where(c => OccurrencesOf(charCounts, c) > 10)
|
---|
455 | .OrderBy(c => -OccurrencesOf(charCounts, c))
|
---|
456 | .DefaultIfEmpty(' ')
|
---|
457 | .First();
|
---|
458 | } else if (OccurrencesOf(charCounts, ',') > 10) {
|
---|
459 | // no points and many commas
|
---|
460 | // count the number of tokens (chains of only digits and commas) that contain multiple comma characters
|
---|
461 | int tokensWithMultipleCommas = 0;
|
---|
462 | for (int i = 0; i < charsRead; i++) {
|
---|
463 | int nCommas = 0;
|
---|
464 | while (i < charsRead && (buffer[i] == ',' || Char.IsDigit(buffer[i]))) {
|
---|
465 | if (buffer[i] == ',') nCommas++;
|
---|
466 | i++;
|
---|
467 | }
|
---|
468 | if (nCommas > 2) tokensWithMultipleCommas++;
|
---|
469 | }
|
---|
470 | if (tokensWithMultipleCommas > 1) {
|
---|
471 | // English format (only integer values) with ',' as separator
|
---|
472 | numberFormat = NumberFormatInfo.InvariantInfo;
|
---|
473 | dateTimeFormatInfo = DateTimeFormatInfo.InvariantInfo;
|
---|
474 | separator = ',';
|
---|
475 | } else {
|
---|
476 | char[] disallowedSeparators = new char[] { ',' }; // n. def. contains a space so ' ' should be disallowed to, however existing unit tests would fail
|
---|
477 | // German format (real values)
|
---|
478 | numberFormat = NumberFormatInfo.GetInstance(new CultureInfo("de-DE"));
|
---|
479 | dateTimeFormatInfo = DateTimeFormatInfo.GetInstance(new CultureInfo("de-DE"));
|
---|
480 | separator = POSSIBLE_SEPARATORS
|
---|
481 | .Except(disallowedSeparators)
|
---|
482 | .Where(c => OccurrencesOf(charCounts, c) > 10)
|
---|
483 | .OrderBy(c => -OccurrencesOf(charCounts, c))
|
---|
484 | .DefaultIfEmpty(' ')
|
---|
485 | .First();
|
---|
486 | }
|
---|
487 | } else {
|
---|
488 | // no points and no commas => English format
|
---|
489 | numberFormat = NumberFormatInfo.InvariantInfo;
|
---|
490 | dateTimeFormatInfo = DateTimeFormatInfo.InvariantInfo;
|
---|
491 | separator = POSSIBLE_SEPARATORS
|
---|
492 | .Where(c => OccurrencesOf(charCounts, c) > 10)
|
---|
493 | .OrderBy(c => -OccurrencesOf(charCounts, c))
|
---|
494 | .DefaultIfEmpty(' ')
|
---|
495 | .First();
|
---|
496 | }
|
---|
497 | }
|
---|
498 | }
|
---|
499 |
|
---|
500 | private static int OccurrencesOf(Dictionary<char, int> charCounts, char c) {
|
---|
501 | return charCounts.ContainsKey(c) ? charCounts[c] : 0;
|
---|
502 | }
|
---|
503 |
|
---|
504 | #region tokenizer
|
---|
505 | // the tokenizer reads full lines and returns separated tokens in the line as well as a terminating end-of-line character
|
---|
506 | internal enum TokenTypeEnum {
|
---|
507 | NewLine, String, Double, DateTime, Missing
|
---|
508 | }
|
---|
509 |
|
---|
510 | internal class Tokenizer {
|
---|
511 | private StreamReader reader;
|
---|
512 | // we assume that a buffer of 1024 tokens for a line is sufficient most of the time (the buffer is increased below if necessary)
|
---|
513 | private TokenTypeEnum[] tokenTypes = new TokenTypeEnum[1024];
|
---|
514 | private string[] stringVals = new string[1024];
|
---|
515 | private double[] doubleVals = new double[1024];
|
---|
516 | private DateTime[] dateTimeVals = new DateTime[1024];
|
---|
517 | private int tokenPos;
|
---|
518 | private int numTokens;
|
---|
519 | private NumberFormatInfo numberFormatInfo;
|
---|
520 | private DateTimeFormatInfo dateTimeFormatInfo;
|
---|
521 | private char separator;
|
---|
522 |
|
---|
523 | // arrays for string.Split()
|
---|
524 | private readonly char[] whiteSpaceSeparators = new char[0]; // string split uses separators as default
|
---|
525 | private readonly char[] separators;
|
---|
526 |
|
---|
527 | private int currentLineNumber = 0;
|
---|
528 | public int CurrentLineNumber {
|
---|
529 | get { return currentLineNumber; }
|
---|
530 | private set { currentLineNumber = value; }
|
---|
531 | }
|
---|
532 | private string currentLine;
|
---|
533 | public string CurrentLine {
|
---|
534 | get { return currentLine; }
|
---|
535 | private set { currentLine = value; }
|
---|
536 | }
|
---|
537 | public long BytesRead {
|
---|
538 | get;
|
---|
539 | private set;
|
---|
540 | }
|
---|
541 |
|
---|
542 | public Tokenizer(StreamReader reader, NumberFormatInfo numberFormatInfo, DateTimeFormatInfo dateTimeFormatInfo, char separator) {
|
---|
543 | this.reader = reader;
|
---|
544 | this.numberFormatInfo = numberFormatInfo;
|
---|
545 | this.dateTimeFormatInfo = dateTimeFormatInfo;
|
---|
546 | this.separator = separator;
|
---|
547 | this.separators = new char[] { separator };
|
---|
548 | ReadNextTokens();
|
---|
549 | }
|
---|
550 |
|
---|
551 | public bool HasNext() {
|
---|
552 | return numTokens > tokenPos || !reader.EndOfStream;
|
---|
553 | }
|
---|
554 |
|
---|
555 | public TokenTypeEnum PeekType() {
|
---|
556 | return tokenTypes[tokenPos];
|
---|
557 | }
|
---|
558 |
|
---|
559 | public void Skip() {
|
---|
560 | // simply skips one token without returning the result values
|
---|
561 | tokenPos++;
|
---|
562 | if (numTokens == tokenPos) {
|
---|
563 | ReadNextTokens();
|
---|
564 | }
|
---|
565 | }
|
---|
566 |
|
---|
567 | public void Next(out TokenTypeEnum type, out string strVal, out double dblVal, out DateTime dateTimeVal) {
|
---|
568 | type = tokenTypes[tokenPos];
|
---|
569 | strVal = stringVals[tokenPos];
|
---|
570 | dblVal = doubleVals[tokenPos];
|
---|
571 | dateTimeVal = dateTimeVals[tokenPos];
|
---|
572 | Skip();
|
---|
573 | }
|
---|
574 |
|
---|
575 | private void ReadNextTokens() {
|
---|
576 | if (!reader.EndOfStream) {
|
---|
577 | CurrentLine = reader.ReadLine();
|
---|
578 | CurrentLineNumber++;
|
---|
579 | if (reader.BaseStream.CanSeek) {
|
---|
580 | BytesRead = reader.BaseStream.Position;
|
---|
581 | } else {
|
---|
582 | BytesRead += CurrentLine.Length + 2; // guess
|
---|
583 | }
|
---|
584 | int i = 0;
|
---|
585 | if (!string.IsNullOrWhiteSpace(CurrentLine)) {
|
---|
586 | foreach (var tok in Split(CurrentLine)) {
|
---|
587 | TokenTypeEnum type;
|
---|
588 | double doubleVal;
|
---|
589 | DateTime dateTimeValue;
|
---|
590 | type = TokenTypeEnum.String; // default
|
---|
591 | stringVals[i] = tok.Trim();
|
---|
592 | if (double.TryParse(tok, NumberStyles.Float, numberFormatInfo, out doubleVal)) {
|
---|
593 | type = TokenTypeEnum.Double;
|
---|
594 | doubleVals[i] = doubleVal;
|
---|
595 | } else if (DateTime.TryParse(tok, dateTimeFormatInfo, DateTimeStyles.NoCurrentDateDefault, out dateTimeValue)
|
---|
596 | && (dateTimeValue.Year > 1 || dateTimeValue.Month > 1 || dateTimeValue.Day > 1)// if no date is given it is returned as 1.1.0001 -> don't allow this
|
---|
597 | ) {
|
---|
598 | type = TokenTypeEnum.DateTime;
|
---|
599 | dateTimeVals[i] = dateTimeValue;
|
---|
600 | } else if (string.IsNullOrWhiteSpace(tok)) {
|
---|
601 | type = TokenTypeEnum.Missing;
|
---|
602 | }
|
---|
603 |
|
---|
604 | // couldn't parse the token as an int or float number or datetime value so return a string token
|
---|
605 |
|
---|
606 | tokenTypes[i] = type;
|
---|
607 | i++;
|
---|
608 |
|
---|
609 | if (i >= tokenTypes.Length) {
|
---|
610 | // increase buffer size if necessary
|
---|
611 | IncreaseCapacity(ref tokenTypes);
|
---|
612 | IncreaseCapacity(ref doubleVals);
|
---|
613 | IncreaseCapacity(ref stringVals);
|
---|
614 | IncreaseCapacity(ref dateTimeVals);
|
---|
615 | }
|
---|
616 | }
|
---|
617 | }
|
---|
618 | tokenTypes[i] = TokenTypeEnum.NewLine;
|
---|
619 | numTokens = i + 1;
|
---|
620 | tokenPos = 0;
|
---|
621 | }
|
---|
622 | }
|
---|
623 |
|
---|
624 | private IEnumerable<string> Split(string line) {
|
---|
625 | return separator == WHITESPACECHAR ?
|
---|
626 | line.Split(whiteSpaceSeparators, StringSplitOptions.RemoveEmptyEntries) :
|
---|
627 | line.Split(separators);
|
---|
628 | }
|
---|
629 |
|
---|
630 | private static void IncreaseCapacity<T>(ref T[] arr) {
|
---|
631 | int n = (int)Math.Floor(arr.Length * 1.7); // guess
|
---|
632 | T[] arr2 = new T[n];
|
---|
633 | Array.Copy(arr, arr2, arr.Length);
|
---|
634 | arr = arr2;
|
---|
635 | }
|
---|
636 | }
|
---|
637 | #endregion
|
---|
638 |
|
---|
639 | #region parsing
|
---|
640 |
|
---|
641 | private void ParseVariableNames() {
|
---|
642 | // the first line must contain variable names
|
---|
643 | List<string> varNames = new List<string>();
|
---|
644 |
|
---|
645 | TokenTypeEnum type;
|
---|
646 | string strVal;
|
---|
647 | double dblVal;
|
---|
648 | DateTime dateTimeVal;
|
---|
649 |
|
---|
650 | tokenizer.Next(out type, out strVal, out dblVal, out dateTimeVal);
|
---|
651 |
|
---|
652 | // the first token must be a variable name
|
---|
653 | if (type != TokenTypeEnum.String)
|
---|
654 | throw new ArgumentException("Error: Expected " + TokenTypeEnum.String + " got " + type);
|
---|
655 | varNames.Add(strVal);
|
---|
656 |
|
---|
657 | while (tokenizer.HasNext() && tokenizer.PeekType() != TokenTypeEnum.NewLine) {
|
---|
658 | tokenizer.Next(out type, out strVal, out dblVal, out dateTimeVal);
|
---|
659 | varNames.Add(strVal);
|
---|
660 | }
|
---|
661 | ExpectType(TokenTypeEnum.NewLine);
|
---|
662 |
|
---|
663 | variableNames = varNames;
|
---|
664 | }
|
---|
665 |
|
---|
666 | private void ExpectType(TokenTypeEnum expectedToken) {
|
---|
667 | if (tokenizer.PeekType() != expectedToken)
|
---|
668 | throw new ArgumentException("Error: Expected " + expectedToken + " got " + tokenizer.PeekType());
|
---|
669 | tokenizer.Skip();
|
---|
670 | }
|
---|
671 |
|
---|
672 | private void Error(string message, string token, int lineNumber) {
|
---|
673 | throw new IOException(string.Format("Error while parsing. {0} (token: {1} lineNumber: {2}).", message, token, lineNumber));
|
---|
674 | }
|
---|
675 | #endregion
|
---|
676 | }
|
---|
677 | }
|
---|