Color schemes

Color schemes#

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Let’s compare the color schemes and discuss around the following aspects:

  • Data Suitability: How well does the color scheme convey the nature of the data? Is it sequential, diverging, or qualitative?

  • Visual Perception: Does the color scheme offer a perceptually uniform progression, making it easy to interpret changes in data values?

  • Accessibility: How accessible is the color scheme for people with color vision deficiencies?

  • Emotional Impact: Do certain colors evoke specific emotions or cultural associations that could influence the interpretation of the data?

[4]:

import geopandas as gpd
import matplotlib.pyplot as plt
import ipywidgets as widgets
from IPython.display import display, clear_output
# Load the GeoPackage data
data_path = 'data/helsinki_region_travel_times_to_railway_station.gpkg'
gdf = gpd.read_file(data_path)
gdf = gdf[gdf['pt_r_t'] > 0]
# Create the dropdown widget for color scheme selection
color_dropdown = widgets.Dropdown(
    options=['viridis', 'plasma', 'inferno', 'magma', 'cividis'],
    value='viridis',
    description='Color Scheme:',
)

# Create an output widget to manage the plot output
color_dropdown = widgets.Dropdown(
    options=[
        'viridis', 'plasma', 'inferno', 'magma', 'cividis',
        'coolwarm', 'Spectral', 'spring', 'summer', 'autumn',
        'winter', 'Wistia', 'hot', 'afmhot', 'gist_heat',
        'copper', 'PiYG', 'PRGn', 'BrBG', 'PuOr',
        'RdGy', 'RdBu', 'RdYlBu', 'RdYlGn', 'Spectral',
        'cool', 'rainbow', 'jet', 'hsv'
    ],
    value='viridis',
    description='Color Scheme:',
)

# Create an output widget to manage the plot output
plot_output = widgets.Output()

def plot_map(color_scheme):
    with plot_output:
        clear_output(wait=True)  # Clear the previous plot
        fig, ax = plt.subplots(figsize=(10, 10))
        gdf.plot(column='pt_r_t', cmap=color_scheme, legend=True, ax=ax,  legend_kwds={"label": "Travel time (min)", "location":"left", "shrink": 0.5} )
        plt.title(f'Helsinki Region Travel Times with "{color_scheme}" Color Scheme')
        # Hide the axis labels
        ax.set_xlabel('')
        ax.set_ylabel('')

        # Hide the tick marks and labels on both axes
        ax.tick_params(axis='both', which='both', length=0)
        ax.set_xticklabels([])
        ax.set_yticklabels([])
        ax.xaxis.set_ticks_position('none')
        ax.yaxis.set_ticks_position('none')
        plt.show()

def on_color_change(change):
    plot_map(change.new)

color_dropdown.observe(on_color_change, names='value')

# Display the widgets
display(color_dropdown, plot_output)