improved NeXus docu.

src/external/nexus/Usage.md

@@ -99,6 +99,15 @@ switch (type) {
 | `HDF5` | HDF5 format | `0x89 'H' 'D' 'F' 0x0d 0x0a 0x1a 0x0a` |
 | `Unknown` | Unrecognized format | - |
 
+### Timestamp Utility
+
+Generate an ISO 8601 local timestamp string:
+
+```cpp
+std::string timestamp = nxs::getIso8601TimestampLocal();
+// Returns e.g. "2026-02-08T14:30:00"
+```
+
 ---
 
 ## Reading NeXus Files

src/external/nexus/examples/hdf4/docu/README.md

@@ -136,16 +136,6 @@ Code migration typically requires only:
 - `H4DataType::INT8` - 8-bit signed integer
 - `H4DataType::UINT8` - 8-bit unsigned integer
 
-## Documentation
-
-Generate Doxygen documentation (if Doxygen is installed):
-
-```bash
-make doc
-```
-
-Documentation will be generated in the `doc/html` directory.
-
 ## Differences from HDF5
 
 HDF4 has some limitations compared to HDF5:

src/external/nexus/examples/hdf5/docu/README.md

@@ -5,194 +5,51 @@ This directory contains documentation for the h5nexus project.
 ## Available Documentation
 
 - **Usage.md** - Comprehensive usage guide with detailed examples and workflow patterns
-- **mainpage.md** - Main page for Doxygen-generated API documentation
 
-## Generating API Documentation
+## Project Structure
 
-The project uses [Doxygen](https://www.doxygen.nl/) to generate comprehensive API documentation from source code comments.
+The h5nexus example project has the following structure:
+
+```
+h5nexus/
+├── CMakeLists.txt          - Build configuration
+├── main.cpp                - Main program source
+├── git_revision.sh         - Git revision header generator
+├── cmake/
+│   ├── config.h.in         - CMake config template
+│   └── git-revision.h.in   - Git revision template
+└── docu/
+    ├── README.md           - This file
+    └── Usage.md            - Detailed usage documentation
+```
+
+## Building
+
+```bash
+mkdir build
+cd build
+cmake ..
+make
+```
 
 ### Prerequisites
 
-- **Doxygen** (required) - Install with:
+- CMake >= 3.26
-  ```bash
+- C++17 compatible compiler
-  # macOS
+- HDF5 C++ library
-  brew install doxygen
+- ROOT >= 6.36 with Minuit2
 
-  # Ubuntu/Debian
+## Key Classes
-  sudo apt-get install doxygen
 
-  # Fedora/RHEL
+The h5nexus example uses the PNeXus library which provides:
-  sudo dnf install doxygen
-  ```
 
-- **Graphviz** (optional, recommended) - For generating diagrams:
+- `nxH5::PNeXus` - Main NeXus file reader/writer class
-  ```bash
+- `nxH5::PNXdata<T>` - Template class for dataset storage
-  # macOS
+- `nxH5::PNeXusDeadTime` - Dead time correction calculator
-  brew install graphviz
+- `nxs::checkHDFType()` - File format detection
-
-  # Ubuntu/Debian
-  sudo apt-get install graphviz
-
-  # Fedora/RHEL
-  sudo dnf install graphviz
-  ```
-
-### Method 1: Using CMake (Recommended)
-
-If you've already configured your build with CMake:
-
-```bash
-cd build
-make doc
-```
-
-This will generate HTML documentation in the `doc/html/` directory.
-
-### Method 2: Using Doxygen Directly
-
-From the project root directory:
-
-```bash
-doxygen Doxyfile
-```
-
-This will also generate HTML documentation in the `doc/html/` directory.
-
-## Viewing the Documentation
-
-After generation, open the main documentation page in your web browser:
-
-```bash
-# macOS
-open doc/html/index.html
-
-# Linux
-xdg-open doc/html/index.html
-
-# Or manually navigate to: file:///path/to/h5nexus/doc/html/index.html
-```
-
-## Documentation Structure
-
-The generated documentation includes:
-
-- **Main Page** - Overview, quick start guide, and architecture description
-- **Classes** - Detailed documentation for all classes:
-  - `nxH5::PNeXus` - Main NeXus file reader/writer class
-  - `nxH5::PNXdata<T>` - Template class for dataset storage
-  - `nxH5::PNeXusDeadTime` - Dead time correction calculator
-- **Files** - Source file documentation
-- **Namespaces** - Namespace documentation (nxH5)
-- **Examples** - Code examples from the documentation
-- **Class Hierarchy** - Visual class inheritance diagrams
-- **Call Graphs** - Function call graphs (if Graphviz is available)
-- **Include Dependency Graphs** - Header file dependency visualization
-
-## Documentation Features
-
-The Doxygen configuration includes:
-
-- **Full source browsing** - Browse annotated source code
-- **Search functionality** - Fast search across all documentation
-- **Interactive SVG diagrams** - Zoomable class and call graphs
-- **Cross-references** - Links between related classes and functions
-- **Syntax highlighting** - Colored code examples
-- **Responsive layout** - Works on desktop and mobile browsers
-
-## Configuration
-
-The Doxygen configuration is stored in `Doxyfile` at the project root. Key settings:
-
-- **Input files**: `inc/`, `src/`, `docu/mainpage.md`
-- **Output directory**: `doc/`
-- **Output format**: HTML (LaTeX disabled)
-- **Graphs**: Enabled if Graphviz/dot is available
-- **Extract all**: Yes (documents all code, not just documented items)
-- **Source browser**: Enabled
-
-## Updating Documentation
-
-To update the documentation after code changes:
-
-1. Edit Doxygen comments in header/source files
-2. Regenerate documentation: `make doc` or `doxygen Doxyfile`
-3. Refresh your browser to see changes
-
-### Doxygen Comment Style
-
-The project uses Javadoc-style comments:
-
-```cpp
-/**
- * @brief Brief description of the function
- *
- * Detailed description with more information about what
- * the function does, how it works, and any important notes.
- *
- * @param arg1 Description of first parameter
- * @param arg2 Description of second parameter
- * @return Description of return value
- * @throws ExceptionType Description of when this exception is thrown
- *
- * @note Important note about usage
- * @warning Warning about potential issues
- *
- * @example
- * @code
- * // Example usage
- * MyClass obj;
- * obj.myFunction(42, "test");
- * @endcode
- */
-void myFunction(int arg1, const std::string& arg2);
-```
-
-## Cleaning Generated Documentation
-
-To remove generated documentation:
-
-```bash
-rm -rf doc/html/
-```
-
-## Troubleshooting
-
-### "Doxygen not found" during CMake configuration
-
-Install Doxygen (see Prerequisites above), then reconfigure:
-
-```bash
-cd build
-cmake ..
-```
-
-### Graphs/diagrams not generating
-
-Install Graphviz (see Prerequisites above), then regenerate:
-
-```bash
-make doc
-# or
-doxygen Doxyfile
-```
-
-### Broken links in documentation
-
-Ensure all referenced files exist and paths in Doxyfile are correct. The documentation system expects:
-- Source files in `inc/` and `src/`
-- Main page at `docu/mainpage.md`
-
-### Documentation looks outdated
-
-Clear the output directory and regenerate:
-
-```bash
-rm -rf doc/html/
-make doc
-```
 
 ## Additional Resources
 
 - [Doxygen Manual](https://www.doxygen.nl/manual/)
-- [Doxygen Special Commands](https://www.doxygen.nl/manual/commands.html)
+- [HDF5 Documentation](https://portal.hdfgroup.org/documentation/)
-- [Markdown Support in Doxygen](https://www.doxygen.nl/manual/markdown.html)
+- [NeXus Format](https://www.nexusformat.org/)

src/external/nexus/examples/hdf5/docu/Usage.md

@@ -2028,7 +2028,6 @@ Debug output shows:
 
 ## Additional Resources
 
-- **PNXdata Usage**: See `PNXdata_usage.md` for detailed PNXdata examples
 - **HDF5 Documentation**: https://portal.hdfgroup.org/documentation/index.html
 - **NeXus Format**: https://www.nexusformat.org/
 - **ISIS NeXus**: https://www.isis.stfc.ac.uk/Pages/NeXus-Muon-Data.aspx