### Install Iris Sample Data

Source: https://github.com/scitools/iris/blob/main/docs/src/installing.rst

Commands to install the Iris sample data, which is required to run examples in the gallery, using either Conda or Pip.

```Shell
conda install -c conda-forge iris-sample-data
```

```Shell
pip install iris-sample-data
```

--------------------------------

### Iris Cube Test Setup

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/navigating_a_cube.rst

Initial setup for loading an Iris cube from a sample data path, used for subsequent examples. This block is typically used for testing or demonstration environments.

```python
import iris
filename = iris.sample_data_path('rotated_pole.nc')
cube = iris.load_cube(filename)
coord_names = [coord.name() for coord in cube.coords()]
coord = cube.coord('grid_latitude')
```

--------------------------------

### Setup for Iris Interpolation Examples

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/interpolation_and_regridding.rst

Initializes necessary libraries like NumPy and Iris, and configures warnings to be ignored for the subsequent examples.

```Python
import numpy as np
import iris
import warnings
warnings.simplefilter('ignore')
```

--------------------------------

### Iris: Setup for Metadata Examples

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/metadata.rst

Initializes an Iris cube by loading sample data from 'A1B_north_america.nc', used as a prerequisite for subsequent metadata examples.

```python
import iris
cube = iris.load_cube(iris.sample_data_path("A1B_north_america.nc"))
```

--------------------------------

### Update Iris Installation Guide for WSL

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/3.0.rst

The `installing_iris` documentation section was updated to include a reference to Windows Subsystem for Linux (WSL) for installation guidance.

```APIDOC
Documentation Section: installing_iris
  Content: Added reference to Windows Subsystem for Linux.
```

--------------------------------

### Run Iris Test Suite

Source: https://github.com/scitools/iris/blob/main/docs/src/installing.rst

Command to execute the Iris test suite, ensuring that the development setup is correctly configured and functional.

```Shell
pytest
```

--------------------------------

### Configure Iris Custom Site Settings

Source: https://github.com/scitools/iris/blob/main/docs/src/installing.rst

Example configuration snippet for `iris/etc/site.cfg` to override default system settings, such as specifying a non-standard path for the `dot` executable. This allows for custom environment adjustments.

```INI
[System]
dot_path = /usr/bin/dot
```

--------------------------------

### Setup for Lenient Cube Maths Example

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/lenient_maths.rst

Initializes `experiment` and `control` Cube objects for demonstrating lenient cube maths. It loads a sample cube, modifies its attributes, and removes certain coordinates to create distinct but related cubes for the example.

```python
import iris
from iris.common import LENIENT
experiment = iris.load_cube(iris.sample_data_path("hybrid_height.nc"), "air_potential_temperature")
control = experiment[0]
control.remove_aux_factory(control.aux_factory())
for coord in ["sigma", "forecast_reference_time", "forecast_period", "atmosphere_hybrid_height_coordinate", "surface_altitude"]:
    control.remove_coord(coord)
control.attributes["Conventions"] = "CF-1.7"
experiment.attributes["experiment-id"] = "RT3 50"
```

--------------------------------

### Install pre-commit using pip

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_code_formatting.rst

This command installs the `pre-commit` tool into your Python development environment using the `pip` package manager. It is the recommended way to get `pre-commit` if you are managing your environment with `pip`.

```bash
$ pip install pre-commit
```

--------------------------------

### Improved Developer Setup with Conda

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/3.0.rst

The developer setup process for Iris has been improved, with curated conda environment YAML files making it easier to configure and install dependencies from source.

```Python
Developer Setup:
  - Curated conda environment YAML files available.
  - Simplifies dependency management for source installations.
```

--------------------------------

### Example Git Status Output

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/gitwash/development_workflow.rst

This is an example of the output from the `git status` command. It shows files that have been modified but not yet staged for commit, and untracked files that are not yet under version control, guiding the user on how to proceed.

```Shell
# On branch ny-new-feature
# Changed but not updated:
#   (use "git add <file>..." to update what will be committed)
#   (use "git checkout -- <file>..." to discard changes in working directory)
#
#	modified:   README
#
# Untracked files:
#   (use "git add <file>..." to include in what will be committed)
#
#	INSTALL
no changes added to commit (use "git add" and/or "git commit -a")
```

--------------------------------

### Python Setup for Iris Warning Examples

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/filtering_warnings.rst

This setup code initializes Iris, configures warning handling for doctests to ensure warnings are visible and paths are relative. It also defines `my_operation()`, a hypothetical function designed to trigger specific Iris warnings for demonstration.

```python
from pathlib import Path
import sys
import warnings

import iris
import iris.coord_systems
import iris.warnings

# Hack to ensure doctests actually see Warnings that are raised, and that
#  they have a relative path (so a test pass is not machine-dependent).
warnings.filterwarnings("default")
IRIS_FILE = Path(iris.__file__)
def custom_warn(message, category, filename, lineno, file=None, line=None):
    filepath = Path(filename)
    filename = str(filepath.relative_to(IRIS_FILE.parents[1]))
    sys.stdout.write(warnings.formatwarning(message, category, filename, lineno))
warnings.showwarning = custom_warn

geog_cs_globe = iris.coord_systems.GeogCS(6400000)
orthographic_coord_system = iris.coord_systems.Orthographic(
    longitude_of_projection_origin=0,
    latitude_of_projection_origin=0,
    ellipsoid=geog_cs_globe,
)


def my_operation():
    geog_cs_globe.inverse_flattening = 0.1
    _ = orthographic_coord_system.as_cartopy_crs()
```

--------------------------------

### Replace unittest setUp() with pytest fixture

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_pytest_conversions.rst

This snippet demonstrates how to replace the unittest setUp() method with a pytest fixture. The _setup() function, decorated with @pytest.fixture(autouse=True), will automatically run before each test, serving the same purpose as setUp() in unittest.

```python
@pytest.fixture(autouse=True)
def _setup(self):
   ...
```

--------------------------------

### Python: Import necessary libraries for Iris data examples

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/real_and_lazy_data.rst

This setup block imports `dask.array`, `iris`, `iris.cube.CubeList`, and `numpy` to prepare the environment for demonstrating Iris data concepts, including lazy and real data handling.

```python
import dask.array as da
import iris
from iris.cube import CubeList
import numpy as np
```

--------------------------------

### Install Released Iris Library

Source: https://github.com/scitools/iris/blob/main/docs/src/installing.rst

Instructions for installing the stable release of the Iris library using either the Conda package manager from conda-forge or Pip from PyPI.

```Shell
conda install -c conda-forge iris
```

```Shell
pip install scitools-iris
```

--------------------------------

### Example output of git commit with pre-commit hooks

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_code_formatting.rst

This snippet shows the typical output when performing a `git commit` after `pre-commit` hooks have been installed. It illustrates how various checks (like `black` and `flake8`) are run automatically, indicating their status (Passed, Skipped, etc.) before the commit is finalized.

```bash
Check for added large files..............................................Passed
Check for merge conflicts................................................Passed
Debug Statements (Python)............................(no files to check)Skipped
Don't commit to branch...................................................Passed
black................................................(no files to check)Skipped
flake8...............................................(no files to check)Skipped
[contribution_overhaul c8513187] this is my commit message
2 files changed, 10 insertions(+), 9 deletions(-)
```

--------------------------------

### Start Jupyter Notebook Server

Source: https://github.com/scitools/iris/blob/main/docs/gallery_code/README.rst

After downloading the gallery notebooks, execute this command in your terminal to launch the Jupyter notebook server. This will open a web browser interface where you can access and run the downloaded notebooks.

```bash
jupyter notebook
```

--------------------------------

### Inspect contents of loaded Iris CubeList

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/loading_iris_cubes.rst

Shows how to print the `CubeList` returned by `iris.load` to get a high-level overview of the loaded cubes, including their names, units, and primary dimensions. This example uses a sample PP file.

```python
>>> import iris
>>> filename = iris.sample_data_path('uk_hires.pp')
>>> cubes = iris.load(filename)
>>> print(cubes)
0: air_potential_temperature / (K)     (time: 3; model_level_number: 7; grid_latitude: 204; grid_longitude: 187)
1: surface_altitude / (m)              (grid_latitude: 204; grid_longitude: 187)
```

--------------------------------

### Install Iris Sample Data and Jupyter with Conda

Source: https://github.com/scitools/iris/blob/main/docs/gallery_code/README.rst

This command uses the Conda package manager to install 'iris-sample-data' and 'jupyter' from the 'conda-forge' channel. These packages are required to successfully view and interact with the gallery's Jupyter notebooks locally.

```bash
conda install -c conda-forge iris-sample-data jupyter
```

--------------------------------

### Setup for Lenient Metadata Behaviour Examples

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/lenient_metadata.rst

Initializes an Iris cube and extracts a latitude coordinate, preparing for demonstrations of lenient metadata operations.

```python
import iris
cube = iris.load_cube(iris.sample_data_path("A1B_north_america.nc"))
latitude = cube.coord("latitude")
```

--------------------------------

### Configure GitHub App: Post-Creation Setup

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/github_app.rst

Outlines the essential configuration steps after a GitHub App has been created, including noting the App ID and generating a private key for signing access token requests.

```APIDOC
SciTools settings / iris-actions form:
  About:
    App ID: (Note this value for later use in GHA secrets)
  Display information:
    (Optional) Upload iris logo (png image)
  Private keys:
    Generate a private key: (Click button to generate and download)
```

--------------------------------

### Install pre-commit Git hooks

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_code_formatting.rst

This command installs the Git hooks defined in the project's `.pre-commit-config.yaml` file. Running this from the root directory of the Iris project enables automatic code formatting and linting upon `git commit`.

```bash
$ pre-commit install
```

--------------------------------

### Iris Test Setup for PP and Fieldsfile Handling

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/um_files_loading.rst

Initializes the test environment by importing necessary Iris and NumPy modules and setting NumPy print options for precision.

```python
import numpy as np
import iris
import iris.fileformats.pp
np.set_printoptions(precision=2)
```

--------------------------------

### Setup: Initializing Cube and Area Weights

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/cube_statistics.rst

This setup code loads a sample Iris cube and prepares its geographical coordinates by guessing bounds. It then calculates area weights, which are essential for accurate area-weighted statistical operations on the cube.

```python
import iris
filename = iris.sample_data_path('uk_hires.pp')
cube = iris.load_cube(filename, 'air_potential_temperature')

import iris.analysis.cartography
cube.coord('grid_latitude').guess_bounds()
cube.coord('grid_longitude').guess_bounds()
grid_areas = iris.analysis.cartography.area_weights(cube)
```

--------------------------------

### Example of a Complete What's New Contribution Entry

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/documenting/whats_new_contributions.rst

Provides a full example of a 'What's New' entry, illustrating the reStructuredText auto-enumerated list format, inclusion of multiple contributors (including reviewers), references to Iris classes/methods, issue numbers, and pull request IDs. This serves as a template for new contributions, emphasizing conciseness and user-centric language.

```reStructuredText
#. `@tkknight <https://github.com/tkknight>`_ and
   `@trexfeathers <https://github.com/trexfeathers>`_ (reviewer) changed
   argument ``x`` to be optional in :class:`~iris.module.class` and
   :meth:`iris.module.method`. This allows greater flexibility as requested in
   :issue:`9999`. (:pull:`1111`, :pull:`9999`)
```

--------------------------------

### Install pre-commit using conda

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_code_formatting.rst

This command installs the `pre-commit` tool into your Python development environment using the `conda` package manager. It specifies the 'conda-forge' channel to ensure access to the `pre-commit` package.

```bash
$ conda install -c conda-forge pre-commit
```

--------------------------------

### Inspect Iris Cube Methods and Attributes

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/navigating_a_cube.rst

Illustrates using `dir()` to list available methods and attributes, and `help()` to get detailed documentation for an Iris cube object. This helps in exploring the capabilities of the cube.

```python
dir(cube)
help(cube)
```

--------------------------------

### Install Local Iris Development Source

Source: https://github.com/scitools/iris/blob/main/docs/src/installing.rst

Command to install the local Iris source code in editable mode, allowing changes to the source to be immediately reflected without reinstallation. This command should be run from the root directory of your local Iris copy.

```Shell
pip install --no-deps --editable .
```

--------------------------------

### Create Iris Development Environment

Source: https://github.com/scitools/iris/blob/main/docs/src/installing.rst

Steps to set up a development environment for Iris by creating a Conda environment from the provided `requirements/iris.yml` file and then activating it. This environment includes dependencies for coding, testing, and building documentation.

```Shell
conda env create --file=requirements/iris.yml
conda activate iris-dev
```

--------------------------------

### Run Single Iris Gallery Test by Pattern

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_documentation_full.rst

This command allows you to run a specific gallery example test by using the pytest -k option for pattern matching, useful for focused debugging.

```Shell
pytest -v -k plot_coriolis docs/gallery_tests/test_gallery_examples.py
```

--------------------------------

### Documentation Update: ORCA Grid Reprojection Example

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/1.7.rst

Notes the addition of an example demonstrating data reprojection from 2D auxiliary spatial coordinates, such as those from the ORCA grid.

```APIDOC
Example: plot_orca_projection.py (ORCA grid reprojection)
```

--------------------------------

### Documentation Update: Custom Aggregator Example

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/1.7.rst

Notes the addition of an example demonstrating how to create a custom `iris.analysis.Aggregator`.

```APIDOC
Example: plot_custom_aggregation.py (iris.analysis.Aggregator)
```

--------------------------------

### Install Iris from PyPI for Testing

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/release.rst

These commands deactivate the current conda environment, create a new 'iris-dev' environment from a YAML file, activate it, and then install 'scitools-iris' from PyPI using pip without dependencies for testing purposes.

```Shell
conda deactivate
conda env create --file ./requirements/iris.yml
. activate iris-dev
python -m pip install --no-deps scitools-iris
```

--------------------------------

### Example Pytest Output

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_running_tests.rst

This example displays a trimmed output from a `pytest` session, showing the test progress, summary of passed/skipped tests, and warnings. It highlights common output patterns, including messages for skipped tests due to missing dependencies or external data.

```shell
============================= test session starts ==============================
platform linux -- Python 3.10.5, pytest-7.1.2, pluggy-1.0.0
rootdir: /path/to/git/clone/iris, configfile: pyproject.toml, testpaths: lib/iris
plugins: xdist-2.5.0, forked-1.4.0
gw0 I / gw1 I
gw0 [6361] / gw1 [6361] 

........................................................................ [  1%]
........................................................................ [  2%]
........................................................................ [  3%]
...
.......................ssssssssssssssssss............................... [ 99%]
........................                                                 [100%]
=============================== warnings summary ===============================
...
-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
=========================== short test summary info ============================
SKIPPED [1] lib/iris/tests/experimental/test_raster.py:152: Test requires 'gdal'.
SKIPPED [1] lib/iris/tests/experimental/test_raster.py:155: Test requires 'gdal'.
...
========= 6340 passed, 21 skipped, 1659 warnings in 193.57s (0:03:13) ==========
```

--------------------------------

### Using Iris Plugins

Source: https://github.com/scitools/iris/blob/main/docs/src/community/plugins.rst

Once an Iris plugin is installed, it can be activated using the `iris.use_plugin` function or by directly importing its module from `iris.plugins`.

```python
import iris

iris.use_plugin("my_plugin")
# OR
import iris.plugins.my_plugin
```

--------------------------------

### Documentation Update: Custom Log-Scale Colouring Example

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/1.7.rst

Notes the addition of an example demonstrating custom log-scale colouring in plots.

```APIDOC
Example: plot_anomaly_log_colouring.py
```

--------------------------------

### Run Iris Documentation Doctests

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_documentation_full.rst

This command runs doctests embedded within the documentation pages, verifying that Python code examples are still valid and produce expected outputs.

```Shell
make doctest
```

--------------------------------

### Documentation Gallery Reorganization

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/3.0.rst

The `plot_orca_projection.py` example has been moved from the general gallery to the oceanography section in the documentation.

```Documentation
Documentation Gallery:
  - plot_orca_projection.py moved to oceanography section.
```

--------------------------------

### Clone Your Git Fork and Add Upstream Remote

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/gitwash/set_up_fork.rst

This snippet demonstrates the initial steps to set up your local repository: cloning your personal fork from GitHub, changing into the project directory, and then adding the main SciTools/iris repository as an 'upstream' remote. This allows you to pull changes from the main project.

```bash
git clone git@github.com:your-user-name/iris.git
cd iris
git remote add upstream git@github.com/SciTools/iris.git
```

--------------------------------

### Example Docstring for Python Unit Test Module

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_tests.rst

Illustrates the required docstring format for a unit test module, specifying the exact unit (function or class) being tested within the `iris` project.

```Python
"""Unit tests for the `iris.experimental.raster.export_geotiff` function."""
```

--------------------------------

### Cross-referencing Internal Documents in reST

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/documenting/rest_guide.rst

Shows how to link to other documents within the same project using the `:doc:` role in reStructuredText. This is useful for building interconnected documentation sets.

```reStructuredText
:doc:`document_name`
```

--------------------------------

### Setup for CubeList.merge vs CubeList.merge_cube Comparison

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/merge_and_concat.rst

Initializes a `CubeList` with three identical cubes and adds a 'Conventions' attribute to the first cube, preparing for a comparison of merge methods.

```python
import numpy as np
import iris
def _xy_cube(z):
    cube = iris.cube.Cube(np.arange(20).reshape(4, 5), 'air_temperature', units='kelvin')
    cube.add_dim_coord(iris.coords.DimCoord(range(4), long_name='y'), 0)
    cube.add_dim_coord(iris.coords.DimCoord(range(5), long_name='x'), 1)
    cube.add_aux_coord(iris.coords.DimCoord(z, long_name='z', units='meters'))
    return cube
cubes = iris.cube.CubeList([_xy_cube(1), _xy_cube(2), _xy_cube(3)])
cubes[0].attributes['Conventions'] = 'CF-1.5'
```

--------------------------------

### Iris Plugin setup.cfg Configuration

Source: https://github.com/scitools/iris/blob/main/docs/src/community/plugins.rst

This example shows a minimal `setup.cfg` configuration for an Iris plugin. The package name should ideally include 'iris' and the plugin name. The `packages = find_namespace:` and `where = lib` options are crucial for correctly identifying the namespace package.

```ini
[metadata]
name = iris-my-plugin

[options]
packages = find_namespace:

[options.packages.find]
where = lib
```

--------------------------------

### Install Nox in an existing Conda environment

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_running_tests.rst

Instructions to install the nox package from conda-forge into an already active Conda environment. This is suitable if you prefer to integrate Nox into an existing setup.

```Shell
conda install -c conda-forge nox
```

--------------------------------

### Creating Basic External Links in reST

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/documenting/rest_guide.rst

Demonstrates how to create a simple external hyperlink in reStructuredText using inline syntax. This syntax allows embedding a URL directly within the link text.

```reStructuredText
`Text of the link <https://example.com>`_
```

--------------------------------

### Running Benchmarks Locally with Nox

Source: https://github.com/scitools/iris/blob/main/benchmarks/README.md

Instructions on how to use the Nox 'benchmarks' session to run performance benchmarks locally, including how to access detailed help for the command.

```Shell
nox -s benchmarks -- --help
```

--------------------------------

### Documentation Update: Cube Broadcasting Section

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/1.7.rst

Highlights the addition of a new section on cube broadcasting to the Iris user guide.

```APIDOC
User Guide: cube broadcasting
```

--------------------------------

### Install Nox in a new Conda environment

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_running_tests.rst

Instructions to create a new Conda environment named 'nox' and install the nox package from conda-forge, then activate the environment. This ensures an isolated setup for Nox.

```Shell
conda create -n nox -c conda-forge nox
conda activate nox
```

--------------------------------

### Python: Setup for Iris CubeList.concatenate Example

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/merge_and_concat.rst

This setup code defines a helper function `_xyt_cube` to create sample Iris cubes with varying 't' coordinates and initializes a CubeList with three such cubes for demonstration purposes.

```python
import numpy as np
import iris
def _xyt_cube(t):
    cube = iris.cube.Cube(np.arange(12 * len(t)).reshape(-1, 3, 4), 'air_temperature', units='kelvin')
    cube.add_dim_coord(iris.coords.DimCoord(range(3), long_name='y'), 1)
    cube.add_dim_coord(iris.coords.DimCoord(range(4), long_name='x'), 2)
    cube.add_dim_coord(iris.coords.DimCoord(t, long_name='t'), 0)
    return cube
cubes = iris.cube.CubeList([_xyt_cube(np.arange(31)), _xyt_cube(np.arange(28) + 31), _xyt_cube(np.arange(31) + 59)])
```

--------------------------------

### Iris Plugin Repository Layout Example

Source: https://github.com/scitools/iris/blob/main/docs/src/community/plugins.rst

This snippet illustrates the recommended directory structure for an Iris plugin. It must appear as a folder within `iris/plugins`, and importantly, there should be no `__init__.py` files at higher levels than the plugin itself to ensure proper namespace package behavior.

```text
+ lib
  + iris
    + plugins
      + my_plugin
        - __init__.py
        - (more code...)
- README.md
- pyproject.toml
- setup.cfg
- (other project files...)
```

--------------------------------

### Setup for Iris Cube Concatenation with Time Unit Unification

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/merge_and_concat.rst

Initializes necessary libraries for demonstrating concatenation with time unit differences, preparing for the use of 'iris.util.unify_time_units'.

```python
import numpy as np
```

--------------------------------

### Python: Setup for Iris CubeList.concatenate_cube Comparison

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/merge_and_concat.rst

This setup code prepares sample Iris cubes similar to the previous example, but with an added 'History' attribute to the first cube. This difference in attributes will be used to demonstrate the behavior of `concatenate_cube` when input cubes are inconsistent.

```python
import numpy as np
import iris
def _xyt_cube(t):
    cube = iris.cube.Cube(np.arange(12 * len(t)).reshape(-1, 3, 4), 'air_temperature', units='kelvin')
    cube.add_dim_coord(iris.coords.DimCoord(range(3), long_name='y'), 1)
    cube.add_dim_coord(iris.coords.DimCoord(range(4), long_name='x'), 2)
    cube.add_dim_coord(iris.coords.DimCoord(t, long_name='t'), 0)
    return cube
cubes = iris.cube.CubeList([_xyt_cube(np.arange(31)), _xyt_cube(np.arange(28) + 31), _xyt_cube(np.arange(31) + 59)])
cubes[0].attributes['History'] = 'Created 2010-06-30'
```

--------------------------------

### Running Benchmarks Locally with bm_runner.py

Source: https://github.com/scitools/iris/blob/main/benchmarks/README.md

Instructions on how to directly execute 'benchmarks/bm_runner.py' for running performance benchmarks locally, including how to access detailed help for the script.

```Shell
benchmarks/bm_runner.py --help
```

--------------------------------

### Quick Build Iris Documentation (No Gallery or API)

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_documentation_full.rst

This command performs a quick build of the documentation by skipping both the gallery and the API documentation creation.

```Shell
make html-quick
```

--------------------------------

### Setup for Strict Metadata Behaviour Examples

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/lenient_metadata.rst

Initializes an Iris cube and extracts a latitude coordinate for demonstrating strict metadata operations.

```python
import iris
cube = iris.load_cube(iris.sample_data_path("A1B_north_america.nc"))
latitude = cube.coord("latitude")
```

--------------------------------

### Python: Populate Latitude Metadata Attributes

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/lenient_metadata.rst

Illustrates how to assign a dictionary of attributes to a `latitude` coordinate's metadata in Iris. This setup prepares the metadata for subsequent lenient comparison examples, showing how to modify `latitude.attributes`.

```Python
attributes = {"grinning face": "😀", "neutral face": "😐"}
latitude.attributes = attributes
latitude.metadata  # doctest: +SKIP
```

--------------------------------

### Setup: Create a Sample Iris Cube with Time Series Data

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/subsetting_a_cube.rst

Initializes a sample Iris cube named `long_ts` with a time coordinate representing weekly intervals over several years. This cube is used as a basis for subsequent time constraint examples.

```Python
import datetime
import numpy as np
from iris.time import PartialDateTime
long_ts = iris.cube.Cube(np.arange(150), long_name='data', units='1')
_mondays = iris.coords.DimCoord(7 * np.arange(150), standard_name='time', units='days since 2007-04-09')
long_ts.add_dim_coord(_mondays, 0)
```

--------------------------------

### View Built Iris Documentation in Browser

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_documentation_full.rst

After building the documentation, this command opens the generated HTML documentation in your default web browser.

```Shell
make show
```

--------------------------------

### Python: Setup for Iris Cube Merging Example

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/merge_and_concat.rst

Defines a helper function `_xy_cube` to create a sample Iris cube with `y` and `x` dimensions and a scalar `z` coordinate. It then initializes a `CubeList` named `cubes` with three such cubes, each having a different `z` value, to be used in subsequent merge operations.

```python
import numpy as np
import iris
def _xy_cube(z):
    cube = iris.cube.Cube(np.arange(20).reshape(4, 5), 'air_temperature', units='kelvin')
    cube.add_dim_coord(iris.coords.DimCoord(range(4), long_name='y'), 0)
    cube.add_dim_coord(iris.coords.DimCoord(range(5), long_name='x'), 1)
    cube.add_aux_coord(iris.coords.DimCoord(z, long_name='z', units='meters'))
    return cube
cubes = iris.cube.CubeList([_xy_cube(1), _xy_cube(2), _xy_cube(3)])
```

--------------------------------

### Combining Iris Metadata with `combine` Method

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/metadata.rst

Illustrates the `combine` method for merging Iris metadata instances. It shows how combining identical metadata returns an identical instance, and how combining instances with differing values results in `None` for the non-common members, or common values for identical members. Includes setup code for the examples.

```python
import iris
cube = iris.load_cube(iris.sample_data_path("A1B_north_america.nc"))
longitude = cube.coord("longitude")
```

```python
cube.metadata
```

```python
metadata = cube.metadata.combine(cube.metadata)
cube.metadata == metadata
```

```python
metadata = cube.metadata._replace(standard_name="air_pressure_at_sea_level")
metadata != cube.metadata
metadata.combine(cube.metadata)  # doctest: +SKIP
CubeMetadata(standard_name=None, long_name=None, var_name='air_temperature', units=Unit('K'), attributes={'STASH': STASH(model=1, section=3, item=236), 'Model scenario': 'A1B', 'source': 'Data from Met Office Unified Model 6.05', 'Conventions': 'CF-1.5'}, cell_methods=(CellMethod(method='mean', coord_names=('time',), intervals=('6 hour',), comments=()),))
```

--------------------------------

### Run All Iris Gallery Tests

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_documentation_full.rst

This command executes all tests associated with the documentation gallery entries, ensuring their correctness and functionality.

```Shell
pytest -v docs/gallery_tests/test_gallery_examples.py
```

--------------------------------

### Inspect Iris UGRID Cube and Mesh Properties

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/ugrid/data_model.rst

These doctest examples demonstrate how to query and display various attributes of an Iris Cube that is linked to a UGRID mesh. It shows how to print the cube's summary, access its location, determine its mesh dimension, and get a detailed summary of the associated `MeshXY` object.

```python
>>> print(edge_cube)
edge_data / (K)                     (-- : 6; height: 3)
    Dimension coordinates:
        height                          -          x
    Mesh coordinates:
        latitude                        x          -
        longitude                       x          -
    Mesh:
        name                        my_mesh
        location                    edge

>>> print(edge_cube.location)
edge

>>> print(edge_cube.mesh_dim())
0

>>> print(edge_cube.mesh.summary(shorten=True))
<MeshXY: 'my_mesh'>

>>> print(edge_cube.mesh)
MeshXY : 'my_mesh'
    topology_dimension: 2
    node
        node_dimension: 'Mesh2d_node'
        node coordinates
            <AuxCoord: longitude / (degrees_east)  [...]  shape(5,)>
            <AuxCoord: latitude / (degrees_north)  [...]  shape(5,)>
    edge
        edge_dimension: 'Mesh2d_edge'
        edge_node_connectivity: <Connectivity: unknown / (unknown)  [...]  shape(6, 2)>
        edge coordinates
            <AuxCoord: longitude / (degrees_east)  [...]  shape(6,)>
            <AuxCoord: latitude / (degrees_north)  [...]  shape(6,)>
    face
        face_dimension: 'Mesh2d_face'
        face_node_connectivity: <Connectivity: unknown / (unknown)  [...]  shape(2, 4)>
        face coordinates
            <AuxCoord: longitude / (degrees_east)  [...]  shape(2,)>
            <AuxCoord: latitude / (degrees_north)  [...]  shape(2,)>
    long_name: 'my_mesh'
```

--------------------------------

### Example Git Configuration File Structure

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/gitwash/configure_git.rst

This snippet shows a typical structure of a `.gitconfig` file, located in your home directory. It includes common sections like user, alias, core, and merge, demonstrating how personal Git settings are organized.

```Git Config
[user]
          name = Your Name
          email = you@yourdomain.example.com

  [alias]
          ci = commit -a
          co = checkout
          st = status
          stat = status
          br = branch
          wdiff = diff --color-words

  [core]
          editor = vim

  [merge]
          summary = true
```

--------------------------------

### Add New Wind Speed Plot Example

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/1.10.rst

A new code example, `plot_wind_speed.py`, has been added to the gallery. This example demonstrates the use of a quiver plot to display wind speeds over Lake Victoria.

```APIDOC
Example: sphx_glr_generated_gallery_meteorology_plot_wind_speed.py
  Description: Demonstrates quiver plot for wind speeds over Lake Victoria.
```

--------------------------------

### Documentation Theme and Hosting Update

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/3.0.rst

The Iris documentation has been updated to use a modern Sphinx theme and is now hosted at `https://scitools-iris.readthedocs.io/en/latest/`.

```Documentation
Documentation:
  - Modern Sphinx theme applied.
  - New hosting URL: https://scitools-iris.readthedocs.io/en/latest/
```

--------------------------------

### Overhaul Iris Developers Guide

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/3.0.rst

The Iris developers guide was extensively revised to include new information on contributing to the project and to improve its overall structure.

```APIDOC
Documentation Section: developers_guide
  Content: Overhauled with contributor information and structural improvements.
```

--------------------------------

### Check PyPI Package Description Rendering

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/release.rst

This command uses 'twine check' to verify that the package description in the built artifacts will render correctly on PyPI, ensuring proper display of the project information.

```Shell
python -m twine check dist/*
```

--------------------------------

### Update User Guide on Multi-dimensional Coordinates

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/1.10.rst

A note has been added to the user guide regarding the impossibility of partially collapsing multi-dimensional coordinates, providing important usage constraints.

```APIDOC
User Guide: Multi-dimensional Coordinates
  Update: Added note on impossibility of partial collapsing.
```

--------------------------------

### Add Cube Maths Units Clarification to User Guide

Source: https://github.com/scitools/iris/blob/main/docs/src/whatsnew/3.0.rst

A new section, `cube_maths_combining_units`, was added to the user guide to provide clarity on how units are managed during cube arithmetic operations.

```APIDOC
Documentation Section: cube_maths_combining_units
  Content: Clarifies Unit handling in cube arithmetic.
```

--------------------------------

### Create and Checkout a New Feature Branch

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/gitwash/development_workflow.rst

This sequence of commands first updates your local mirror of the upstream 'trunk', then creates a new feature branch named 'my-new-feature' based on the current state of 'upstream/main', and finally switches your working directory to this new branch. This ensures your new work starts from the latest upstream code.

```Shell
# Update the mirror of trunk
git fetch upstream
# Make new feature branch starting at current trunk
git branch my-new-feature upstream/main
git checkout my-new-feature
```

--------------------------------

### Get Iris Cube String, Representation, and Type

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/navigating_a_cube.rst

Shows how to use standard Python functions like `str()`, `repr()`, and `type()` to get different string representations and the object type of an Iris cube.

```python
print(str(cube))
print(repr(cube))
print(type(cube))
```

--------------------------------

### Get Iris Cube Name Method

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/navigating_a_cube.rst

Shows how to use the `name()` method to get a string representation of the cube's name. This method always returns a string, providing a consistent way to identify the cube.

```python
print(cube.name())
```

--------------------------------

### Build Iris Source Distribution and Wheel

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/release.rst

This command builds the source distribution (.tar.gz) and pure Python wheel (.whl) files for the Iris project from its root directory, populating the './dist' directory.

```Shell
python -m build
```

--------------------------------

### Initial GRIB file loading script without Dask

Source: https://github.com/scitools/iris/blob/main/docs/src/further_topics/dask_best_practices/dask_bags_and_greed.rst

This script demonstrates a common approach to loading GRIB files using the Iris library. It includes a callback function to filter or modify cubes during loading. A sample of 11 GRIB files takes approximately 600 seconds to load, highlighting a performance bottleneck.

```Python
import iris
import glob

fpaths=glob.glob('20190416/*t18z*f???')
cubes = iris.load(fpaths, callback=callback)

def callback(cube, field, fname):
    if field.sections[5]['bitsPerValue'] == 0:
        raise iris.exceptions.IgnoreCubeException
    if field.sections[4]['parameterNumber'] == 20:
        raise iris.exceptions.IgnoreCubeException
    elif field.sections[4]['parameterNumber'] == 234:
        cube.long_name = 'Icing Severity'
```

--------------------------------

### Combined example: interactive plotting and mode check

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/plotting_a_cube.rst

A comprehensive example demonstrating the combined use of enabling interactive mode, plotting data, and checking the interactive status. It highlights that import statements are not necessary to repeat when combining functionalities.

```python
import matplotlib.pyplot as plt
plt.interactive(True)
plt.plot([1, 2, 2.5])
print(plt.isinteractive())
```

--------------------------------

### Python List Multiple Assignment Example

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/loading_iris_cubes.rst

A general Python example demonstrating the use of multiple assignment to unpack elements from a list of a pre-known length and order into separate variables. This is a common Python idiom for handling sequences.

```Python
>>> number_one, number_two = [1, 2]
>>> print(number_one)
1
>>> print(number_two)
2
```

--------------------------------

### Load and Extract Iris Cubes with Multiple Constraints

Source: https://github.com/scitools/iris/blob/main/docs/src/userguide/subsetting_a_cube.rst

Demonstrates loading a sample PP file and extracting cubes based on combined constraints for air temperature, forecast period, and model level. It also shows how to print the loaded cubes and inspect a specific cube's metadata, including dimension, auxiliary, derived, and scalar coordinates, as well as attributes.

```Python
filename = iris.sample_data_path('uk_hires.pp')
cubes = iris.load(filename).extract(air_temp_and_fp_6 & level_10)
print(cubes)
0: air_potential_temperature / (K)     (grid_latitude: 204; grid_longitude: 187)
print(cubes[0])
air_potential_temperature / (K)     (grid_latitude: 204; grid_longitude: 187)
    Dimension coordinates:
        grid_latitude                             x                    -
        grid_longitude                            -                    x
    Auxiliary coordinates:
        surface_altitude                          x                    x
    Derived coordinates:
        altitude                                  x                    x
    Scalar coordinates:
        forecast_period             6.0 hours
        forecast_reference_time     2009-11-19 04:00:00
        level_height                395.0 m, bound=(360.0, 433.3332) m
        model_level_number          10
        sigma                       0.9549927, bound=(0.9589389, 0.95068014)
        time                        2009-11-19 10:00:00
    Attributes:
        STASH                       m01s00i004
        source                      'Data from Met Office Unified Model'
        um_version                  '7.3'
```

--------------------------------

### GitHub Pull Request Description Template

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_documentation_easy.rst

This template is provided by GitHub when creating a pull request, guiding contributors to provide a clear and concise description of their changes, new features, improvements, or bug fixes for reviewers.

```Markdown
### Description
<!-- Provide a clear description about your awesome pull request -->
<!-- Tell us all about your new feature, improvement, or bug fix -->
```

--------------------------------

### Install and Run Ruff for Iris Codebase Compliance

Source: https://github.com/scitools/iris/blob/main/docs/src/developers_guide/contributing_ci_tests.rst

As of Iris 3.8, `ruff` has been adopted to ensure best practices in the codebase. This snippet provides the commands to install `ruff` within the `iris-dev` conda environment and then run it against the Iris project directory to check for compliance.

```Shell
conda activate iris-dev
pip install ruff
cd iris
ruff .
```

--------------------------------

### PP Field Data Structure Example

Source: https://github.com/scitools/iris/blob/main/lib/iris/tests/results/usecases/pp_to_cf_conversion/to_pp/000003000000.16.202.000128.1860.09.01.00.00.b.pp.txt

An example representation of multiple PP Field instances, illustrating the various metadata attributes (e.g., lbyr, lbmon, blev, bplat) and the associated numerical data array. Each field represents data at a specific atmospheric level (blev).

```APIDOC
[PP Field
   lbyr: 1860
   lbmon: 9
   lbdat: 1
   lbhr: 0
   lbmin: 0
   lbsec: 0
   lbyrd: 1860
   lbmond: 12
   lbdatd: 1
   lbhrd: 0
   lbmind: 0
   lbsecd: 0
   lbtim: 422
   lbft: 2156
   lblrec: 7008
   lbcode: 1
   lbhem: 0
   lbrow: 73
   lbnpt: 96
   lbext: 0
   lbpack: 0
   lbrel: 3
   lbfc: 1
   lbcfc: 0
   lbproc: 128
   lbvc: 8
   lbrvc: 0
   lbexp: 0
   lbegin: 0
   lbnrec: 0
   lbproj: 0
   lbtyp: 0
   lblev: 0
   lbrsvd: (0, 0, 0, 0)
   lbsrce: 1111
   lbuser: (1, -99, 0, 16202, 0, 0, 1)
   brsvd: (0.0, 0.0, 0.0, 0.0)
   bdatum: 0.0
   bacc: 0.0
   blev: 200.0
   brlev: 0.0
   bhlev: 0.0
   bhrlev: 0.0
   bplat: 90.0
   bplon: 0.0
   bgor: 0.0
   bzy: 92.499985
   bdy: -2.499999
   bzx: -3.749999
   bdx: 3.749999
   bmdi: -1e+30
   bmks: 1.0
   data: [[11203. 11203. 11203. ... 11203. 11203. 11203.]
 [11201. 11199. 11198. ... 11207. 11205. 11203.]
 [11201. 11199. 11197. ... 11208. 11207. 11204.]
 ...
 [10497. 10495. 10492. ... 10507. 10504. 10501.]
 [10482. 10481. 10480. ... 10488. 10486. 10483.]
 [10502. 10502. 10502. ... 10502. 10502. 10502.]]
, PP Field
   lbyr: 1860
   lbmon: 9
   lbdat: 1
   lbhr: 0
   lbmin: 0
   lbsec: 0
   lbyrd: 1860
   lbmond: 12
   lbdatd: 1
   lbhrd: 0
   lbmind: 0
   lbsecd: 0
   lbtim: 422
   lbft: 2156
   lblrec: 7008
   lbcode: 1
   lbhem: 0
   lbrow: 73
   lbnpt: 96
   lbext: 0
   lbpack: 0
   lbrel: 3
   lbfc: 1
   lbcfc: 0
   lbproc: 128
   lbvc: 8
   lbrvc: 0
   lbexp: 0
   lbegin: 0
   lbnrec: 0
   lbproj: 0
   lbtyp: 0
   lblev: 0
   lbrsvd: (0, 0, 0, 0)
   lbsrce: 1111
   lbuser: (1, -99, 0, 16202, 0, 0, 1)
   brsvd: (0.0, 0.0, 0.0, 0.0)
   bdatum: 0.0
   bacc: 0.0
   blev: 500.0
   brlev: 0.0
   bhlev: 0.0
   bhrlev: 0.0
   bplat: 90.0
   bplon: 0.0
   bgor: 0.0
   bzy: 92.499985
   bdy: -2.499999
   bzx: -3.749999
   bdx: 3.749999
   bmdi: -1e+30
   bmks: 1.0
   data: [[5252. 5252. 5252. ... 5252. 5252. 5252.]
 [5248. 5248. 5248. ... 5249. 5249. 5248.]
 [5250. 5249. 5248. ... 5251. 5250. 5250.]
 ...
 [4873. 4872. 4870. ... 4874. 4874. 4874.]
 [4858. 4857. 4857. ... 4859. 4859. 4859.]
 [4854. 4854. 4854. ... 4854. 4854. 4854.]]
, PP Field
   lbyr: 1860
   lbmon: 9
   lbdat: 1
   lbhr: 0
   lbmin: 0
   lbsec: 0
   lbyrd: 1860
   lbmond: 12
   lbdatd: 1
   lbhrd: 0
   lbmind: 0
   lbsecd: 0
   lbtim: 422
   lbft: 2156
   lblrec: 7008
   lbcode: 1
   lbhem: 0
   lbrow: 73
   lbnpt: 96
   lbext: 0
   lbpack: 0
   lbrel: 3
   lbfc: 1
   lbcfc: 0
   lbproc: 128
   lbvc: 8
   lbrvc: 0
   lbexp: 0
   lbegin: 0
   lbnrec: 0
   lbproj: 0
   lbtyp: 0
   lblev: 0
   lbrsvd: (0, 0, 0, 0)
   lbsrce: 1111
   lbuser: (1, -99, 0, 16202, 0, 0, 1)
   brsvd: (0.0, 0.0, 0.0, 0.0)
   bdatum: 0.0
   bacc: 0.0
   blev: 700.0
   brlev: 0.0
   bhlev: 0.0
   bhrlev: 0.0
   bplat: 90.0
   bplon: 0.0
   bgor: 0.0
   bzy: 92.499985
   bdy: -2.499999
   bzx: -3.749999
   bdx: 3.749999
   bmdi: -1e+30
   bmks: 1.0
   data: [[2818. 2818. 2818. ... 2818. 2818. 2818.]
 [2815. 2816. 2816. ... 2813. 2814. 2815.]
 [2815. 2815. 2815. ... 2814. 2814. 2815.]
 ...
 [2563. 2564. 2566. ... 2555. 2558. 2561.]
 [2555. 2555. 2555. ... 2554. 2555. 2555.]
 [2540. 2540. 2540. ... 2540. 2540. 2540.]]
]
```