# haw2gnu v3.2.3

**Mercurial revision 5770:c90c3015e72d | 2026-05-22**

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## Description

`haw2gnu` reformats **mooring observations** from the **Hawaii Institute** format to the **MATROOS standard**.

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## Usage

```bash
haw2gnu [OPTIONS] file
```

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## Options


| Option             | Description                                                                                                                         |
| ------------------ | ----------------------------------------------------------------------------------------------------------------------------------- |
| `-h`, `--help`     | Show help and exit.                                                                                                                 |
| `-start <MM/YYYY>` | Start date for extraction (format: `MM/YYYY`). Observations **before** this date are ignored.                                       |
| `-end <MM/YYYY>`   | End date for extraction (format: `MM/YYYY`). Observations **after** this date are ignored. **Requires `-start` to be defined.**     |
| `-d`               | Duplicate the input file for **safety** (creates a `.duplicated.dat` file).                                                         |
| `-t`               | Duplicate the input file with **depths multiplied by 1000** (creates a `.truncated.dat` file).                                      |
| `-f <format>`      | Output format: `obs` (default) or `matroos`.                                                                                        |
| `-o <rootname>`    | Output rootname (without extension). If not provided, the input filename is used with the appropriate extension (`.obs` or `.slv`). |


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## Examples

### **Basic Conversion to `obs` Format**

Convert a Hawaii Institute file to `obs` format (default):

```bash
haw2gnu input.dat
```

Output: `input.obs`

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### **Convert to `matroos` Format**

Convert a Hawaii Institute file to `matroos` format:

```bash
haw2gnu -f matroos input.dat
```

Output: `input.slv`

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### **Extract Data for a Specific Period**

Extract observations between **January 2000** and **December 2010**:

```bash
haw2gnu -start 01/2000 -end 12/2010 input.dat
```

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### **Duplicate Input File for Safety**

Create a backup of the input file while processing:

```bash
haw2gnu -d input.dat
```

Output: `input.duplicated.dat` (backup) + `input.obs` (converted file).

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### **Duplicate Input File with Depths ×1000**

Create a copy of the input file with depths multiplied by 1000:

```bash
haw2gnu -t input.dat
```

Output: `input.truncated.dat` (depths ×1000) + `input.obs` (converted file).

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### **Custom Output Rootname**

Specify a custom output filename:

```bash
haw2gnu -o output_root input.dat
```

Output: `output_root.obs`

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### **Combine Options**

Extract data for a specific period, duplicate the input file, and convert to `matroos` format:

```bash
haw2gnu -start 06/2005 -end 06/2015 -d -f matroos -o custom_output input.dat
```

Output:

- `input.duplicated.dat` (backup)
- `custom_output.slv` (converted file)

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## Environment Variables

None.

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## Notes

1. **Date Format**:
  - Dates must be provided in `MM/YYYY` format (e.g., `01/2000` for January 2000).
  - The `-end` option **requires** the `-start` option to be defined.
2. **Input File**:
  - Only **one input file** can be processed at a time.
  - The input file must be in **Hawaii Institute format**.
3. **Output Files**:
  - If `-o` is not specified, the output filename is derived from the input filename:
    - `.obs` extension for `obs` format (default).
    - `.slv` extension for `matroos` format.
4. **Duplication Options**:
  - `-d` creates a **backup** of the input file with `.duplicated.dat` extension.
  - `-t` creates a **modified copy** of the input file with depths multiplied by 1000 and `.truncated.dat` extension.
5. **Deprecated Options**:
  - `-c` (time function tests) is **deprecated** and no longer supported.

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## See Also

- [MATROOS Standard](https://www.matroos.nl/) (for output format details)
- [Hawaii Institute Mooring Data](https://www.soest.hawaii.edu/) (for input format details)