Create regular expressions as easy as a breeze. This node allows you to build, preview, and test your regexes in real time with your real data. Say good bye to creating your regex in KNIME with trial and error, or copying back and forth regular expressions and text between your favorite regex tool and KNIME. The user interface is inspired by RegExr and Regular Expressions 101.
The node uses Java’s Pattern
implementation. For each row or text input, it will extract all
matches. Each capturing group is automatically mapped to a KNIME
column. To define the column names, you can make use of
“named capturing groups”, such as
(?<name>[A-Z-a-z]+).
To exclude groups from the output, define them as “non-capturing group”: (?:).
Usage Example: Extract email addresses from text
For this input text: “Hello, world! mail@palladian.ai The
quick brown fox jumps over the lazy dog. bob@example.com Lorem
ipsum.” and the
\b(?<Local Part>[A-Z0-9._%+-]+)@(?<Domain>[A-Z0-9.-]+\.[A-Z]{2,})\b,
the node will create a KNIME table as follows:
| Full Match | Local Part | Domain |
|---|---|---|
| mail@palladian.ai | palladian.ai | |
| bob@example.com | bob | example.com |
Standalone Mode
The node can be used with an input table, which provides a string column, or in “standalone” mode (when no input table is connected), where you can enter the text into the node dialog. Click the three dots on the node to switch between standalone mode and input table.
Further reading
For a general introduction into regular expressions, have a look at Regular-Expressions.info.
Options
Popular Predecessors
Row Filter (deprecated)10 %- Regex Extractor7 %
- String Manipulation6 %
- Column Filter4 %
- Table Creator4 %
- Path to String3 %
- Concatenate3 %
- Rule-based Row Filter3 %
- GroupBy3 %
- XPath3 %
- Column Expressions (legacy)3 %
Row Splitter (deprecated)2 %- Reference Row Splitter2 %
- Duplicate Row Filter2 %
- Cell Splitter2 %
Column Rename2 %- String to JSON2 %
- Group Loop Start1 %
- Column Renamer1 %
- Ungroup1 %
- Tika Parser1 %
- Rule Engine1 %
- Excel Reader1 %
- Rule-based Row Splitter1 %
- Column Resorter< 1 %
- Joiner< 1 %
- Loop End< 1 %
- Column Merger< 1 %
- Sorter< 1 %
- Chunk Loop Start< 1 %
- String to Date&Time< 1 %
- Missing Value< 1 %
- Row Filter (Labs)< 1 %
- CSV Reader< 1 %
- Line Reader< 1 %
- Nominal Value Row Filter< 1 %
- File Reader< 1 %
- Math Formula< 1 %
- Table Manipulator< 1 %
- Constant Value Column< 1 %
- Unpivot< 1 %
- Index Query< 1 %
- POST Request< 1 %
- Get WebElement Data< 1 %
- Page Source< 1 %
- Webpage Retriever< 1 %
- Table Row to Variable Loop Start< 1 %
- File Reader (Complex Format)< 1 %
- Document Data Extractor< 1 %
- JSON Path< 1 %
- HTML Parser< 1 %
- GET Request< 1 %
- String Manipulation (Multi Column)< 1 %
- Column Combiner< 1 %
- RowID< 1 %
- Reference Row Filter< 1 %
- String to Number< 1 %
- String Splitter (Regex)< 1 %
- Variable to Table Row< 1 %
- Column List Loop Start< 1 %
- Case Converter< 1 %
- Cell Splitter By Position< 1 %
- Number to String< 1 %
- Column Aggregator< 1 %
- Column Splitter< 1 %
- String Replacer< 1 %
- Counter Generation< 1 %
- List Files/Folders< 1 %
- Date Extractor< 1 %
- HTTP Result Data Extractor< 1 %
- Nominal Value Row Splitter< 1 %
- Numeric Row Splitter< 1 %
- Python Script (legacy)< 1 %
- Number Rounder< 1 %
Views
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Workflows
77519 - Extact Image Meta DataKNIME Hub- BGP Full Route Parse OnlyKNIME Forum
- Binary Data not converted to String - Loading Table Preview impossibleKNIME Hub
- cell splitting with identifiersKNIME Forum
- cell splitting with identifiersKNIME Hub
- Show all 36 workflows
Links
- Manipulate data in REGEXby ArjenEX on 2023-08-23forum.knime.com/p/232935
- How can I extract specific hours from a description?by ArjenEX on 2023-09-27forum.knime.com/p/236233
- Regex tutorial / construction site that can be used in Knimeby HansS on 2024-02-13forum.knime.com/p/249457
- Text Processing - MOSAIQ Medical Notesby ArjenEX on 2024-01-01forum.knime.com/p/246075
- Extract period from filenameby ipazin on 2023-04-01forum.knime.com/p/199366
- Show all 17 links
Developers
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