def multi_model_contours(
    cfg,
    metadatas,
):
    """
    Make a multi model comparison plot showing several transect contour plots.

    This tool loads several cubes from the files, checks that the units are
    sensible BGC units, checks for layers, adjusts the titles accordingly,
    determines the ultimate file name and format, then saves the image.

    Parameters
    ----------
    cfg: dict
        the opened global config dictionairy, passed by ESMValTool.
    metadatas: dict
        The metadatas dictionairy for a specific model.

    """
    ####
    # Load the data for each layer as a separate cube
    model_cubes = {}
    regions = {}
    thresholds = {}
    set_y_logscale = True

    for filename in sorted(metadatas):
        cube = iris.load_cube(filename)
        cube = diagtools.bgc_units(cube, metadatas[filename]['short_name'])
        cube = make_depth_safe(cube)
        cubes = make_cube_region_dict(cube)
        model_cubes[filename] = cubes
        for region in model_cubes[filename]:
            regions[region] = True

        # Determine y log scale.
        set_y_logscale = determine_set_y_logscale(cfg, metadatas[filename])

        # Load threshold/thresholds.
        tmp_thresholds = diagtools.load_thresholds(cfg, metadatas[filename])
        for threshold in tmp_thresholds:
            thresholds[threshold] = True

    # Load image format extention
    image_extention = diagtools.get_image_format(cfg)

    # Make a plot for each layer and each threshold
    for region, threshold in itertools.product(regions, thresholds):
        logger.info('plotting threshold: \t%s', threshold)
        title = ''
        plot_details = {}

        # Plot each file in the group
        for index, filename in enumerate(sorted(metadatas)):
            color = diagtools.get_colour_from_cmap(index, len(metadatas))
            linewidth = 1.
            linestyle = '-'
            # Determine line style for MultiModel statistics:
            if 'MultiModel' in metadatas[filename]['dataset']:
                linewidth = 2.
                linestyle = ':'
            # Determine line style for Observations
            if metadatas[filename]['project'] in diagtools.get_obs_projects():
                color = 'black'
                linewidth = 1.7
                linestyle = '-'

            qplt.contour(model_cubes[filename][region], [
                threshold,
            ],
                         colors=[
                             color,
                         ],
                         linewidths=linewidth,
                         linestyles=linestyle,
                         rasterized=True)

            plot_details[filename] = {
                'c': color,
                'ls': linestyle,
                'lw': linewidth,
                'label': metadatas[filename]['dataset']
            }

            if set_y_logscale:
                plt.axes().set_yscale('log')

            title = metadatas[filename]['long_name']
            units = str(model_cubes[filename][region].units)

            add_sea_floor(model_cubes[filename][region])

        # Add title, threshold, legend to plots
        title = ' '.join([
            title,
            str(threshold), units,
            determine_transect_str(model_cubes[filename][region], region)
        ])
        titlify(title)
        plt.legend(loc='best')

        # Saving files:
        if cfg['write_plots']:
            path = diagtools.get_image_path(
                cfg,
                metadatas[filename],
                prefix='MultipleModels',
                suffix='_'.join([
                    'contour_tramsect', region,
                    str(threshold) + image_extention
                ]),
                metadata_id_list=[
                    'field', 'short_name', 'preprocessor', 'diagnostic',
                    'start_year', 'end_year'
                ],
            )

        # Resize and add legend outside thew axes.
        plt.gcf().set_size_inches(9., 6.)
        diagtools.add_legend_outside_right(plot_details,
                                           plt.gca(),
                                           column_width=0.15)

        logger.info('Saving plots to %s', path)
        plt.savefig(path)
        plt.close()
def make_transect_contours(
    cfg,
    metadata,
    filename,
):
    """
    Make a contour plot of the transect for an indivudual model.

    This tool loads the cube from the file, checks that the units are
    sensible BGC units, checks for layers, adjusts the titles accordingly,
    determines the ultimate file name and format, then saves the image.

    Parameters
    ----------
    cfg: dict
        the opened global config dictionairy, passed by ESMValTool.
    metadata: dict
        The metadata dictionairy for a specific model.
    filename: str
        The preprocessed model file.

    """
    # Load cube and set up units
    cube = iris.load_cube(filename)
    cube = diagtools.bgc_units(cube, metadata['short_name'])
    cube = make_depth_safe(cube)

    # Load threshold/thresholds.
    plot_details = {}
    colours = []
    thresholds = diagtools.load_thresholds(cfg, metadata)
    linewidths = [1 for thres in thresholds]
    linestyles = ['-' for thres in thresholds]

    cubes = make_cube_region_dict(cube)
    for region, cube in cubes.items():
        for itr, thres in enumerate(thresholds):
            colour = diagtools.get_colour_from_cmap(itr, len(thresholds))
            label = str(thres) + ' ' + str(cube.units)
            colours.append(colour)
            plot_details[thres] = {
                'c': colour,
                'lw': 1,
                'ls': '-',
                'label': label
            }

        qplt.contour(cube,
                     thresholds,
                     colors=colours,
                     linewidths=linewidths,
                     linestyles=linestyles,
                     rasterized=True)

        # Determine y log scale.
        if determine_set_y_logscale(cfg, metadata):
            plt.axes().set_yscale('log')

        add_sea_floor(cube)

        # Add legend
        diagtools.add_legend_outside_right(plot_details,
                                           plt.gca(),
                                           column_width=0.08,
                                           loc='below')

        # Add title to plot
        title = ' '.join([
            metadata['dataset'], metadata['long_name'],
            determine_transect_str(cube, region)
        ])
        titlify(title)

        # Load image format extention
        image_extention = diagtools.get_image_format(cfg)

        # Determine image filename:
        if metadata['dataset'].find('MultiModel') > -1:
            path = diagtools.folder(
                cfg['plot_dir']) + os.path.basename(filename)
            path.replace('.nc', region + '_transect_contour' + image_extention)
        else:
            path = diagtools.get_image_path(
                cfg,
                metadata,
                suffix=region + 'transect_contour' + image_extention,
            )

        # Saving files:
        if cfg['write_plots']:
            logger.info('Saving plots to %s', path)
            plt.savefig(path)

        plt.close()