altair charts

basic setup

import altair as alt
import pandas as pd

# Sample data
data = pd.DataFrame({
    "x": [1, 2, 3, 4, 5],
    "y": [10, 20, 15, 30, 25]
})

simple line chart

chart = alt.Chart(data).mark_line().encode(
    x="x",
    y="y"
)

chart

bar chart

chart = alt.Chart(data).mark_bar().encode(
    x="x:O",
    y="y:Q"
)

chart

scatter plot

chart = alt.Chart(data).mark_point().encode(
    x="x",
    y="y"
)

chart

area chart

chart = alt.Chart(data).mark_area().encode(
    x="x",
    y="y"
)

chart

encoding with titles & types

chart = alt.Chart(data).mark_line().encode(
    x=alt.X("x:Q", title="X Axis"),
    y=alt.Y("y:Q", title="Y Axis")
)

chart

add color encodings

data["category"] = ["A", "B", "A", "B", "A"]

chart = alt.Chart(data).mark_point(size=100).encode(
    x="x",
    y="y",
    color="category:N"
)

chart

tooltip

chart = alt.Chart(data).mark_point().encode(
    x="x",
    y="y",
    tooltip=["x", "y"]
)

chart

sorting values

chart = alt.Chart(data).mark_bar().encode(
    x=alt.X("x:O", sort="-y"),
    y="y:Q"
)

chart

aggregation ( mean, sum )

chart = alt.Chart(data).mark_bar().encode(
    x="category:N",
    y="mean(y):Q"
)

chart

Grouped bar chart

chart = alt.Chart(data).mark_bar().encode(
    x="x:O",
    y="y:Q",
    color="category:N"
)

chart

stacked bar chart

chart = alt.Chart(data).mark_bar().encode(
    x="x:O",
    y="y:Q",
    color="category:N"
).properties(
    width=400
)

chart

faceting ( small multiples )

chart = alt.Chart(data).mark_point().encode(
    x="x",
    y="y"
).facet(
    column="category:N"
)

chart

interactive ( zoom and pan )

chart = alt.Chart(data).mark_line().encode(
    x="x",
    y="y"
).interactive()

chart

Filtering Data :

chart = alt.Chart(data).transform_filter(
    alt.datum.y > 15
).mark_point().encode(
    x="x",
    y="y"
)

chart

Layer multiple charts

line = alt.Chart(data).mark_line(color="blue").encode(
    x="x",
    y="y"
)

points = alt.Chart(data).mark_point(color="red").encode(
    x="x",
    y="y"
)

chart = line + points
chart

add chart title

chart = alt.Chart(data).mark_line().encode(
    x="x",
    y="y"
).properties(
    title="My Altair Chart"
)

chart

save chart png / html

chart.save("chart.html")   # HTML
chart.save("chart.png")    # Requires altair_saver