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bs_altair module

Some Altair plots.

  • alt_lineplot, alt_superposed_lineplot, alt_superposed_faceted_lineplot
  • alt_plot_fun: plots a function
  • alt_density, alt_faceted_densities: plots the density of x, or of x conditional on a category
  • alt_superposed_faceted_densities: plots the density of x superposed by f and faceted by g
  • alt_scatterplot, alt_scatterplot_with_histo, alt-linked_scatterplots: variants of scatter plots
  • alt_histogram_by, alt_histogram_continuous: histograms of x by y, and of a continuous x
  • alt_stacked_area,alt_stacked_area_facets: stacked area plots
  • plot_parameterized_estimates: plots densities of estimates of coefficients, with the true values, as a function of a parameter
  • plot_true_sim_facets, plot_true_sim2_facets: plot two simulated values and the true values of statistics as a function of a parameter
  • alt_tick_plots: vertically arranged tick plots of variables
  • alt_matrix_heatmap: plots a heatmap of a matrix.

alt_boxes(df, continuous_var, discrete_var, group_var, max_cols=3, title=None, save=None)

horizontal boxplots of df[continuous_var] by df[discrete_var] and df[group_var]

Parameters:

Name Type Description Default
df DataFrame

datframe with the three variables

required
continuous_var str

name of the continuous variable

required
discrete_var str

name of the discrete variable

required
group_var str

name of the grouping variable

required
max_cols int

maximum number of columns. Defaults to 3.

3
title str | None

a plot title. Defaults to None.

None
save str | None

the name of a file to save to (HTML extension will be added). Defaults to None.

None

Returns:

Type Description
Chart

the chart.

Source code in bs_python_utils/bs_altair.py
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def alt_boxes(
    df: pd.DataFrame,
    continuous_var: str,
    discrete_var: str,
    group_var: str,
    max_cols: int = 3,
    title: str | None = None,
    save: str | None = None,
) -> alt.Chart:
    """horizontal boxplots of `df[continuous_var]` by `df[discrete_var]` and
    `df[group_var]`

    Args:
        df: datframe with the three variables
        continuous_var: name of the continuous variable
        discrete_var: name of the discrete variable
        group_var: name of the grouping variable
        max_cols: maximum number of columns. Defaults to 3.
        title: a plot title. Defaults to None.
        save: the name of a file to save to (HTML extension will be added).
            Defaults to None.

    Returns:
        the chart.
    """
    boxes = (
        (
            alt.Chart(df)
            .mark_boxplot()
            .encode(
                x=f"{continuous_var}:Q", y=f"{discrete_var}:O", color=f"{group_var}:N"
            )
            .properties(width=180, height=180)
        )
        .facet(f"{group_var}:N", columns=max_cols)
        .resolve_scale(y="independent")
    )
    if title:
        boxes = boxes.properties(title=title)
    _maybe_save(boxes, save)
    return cast(alt.Chart, boxes)

alt_density(df, str_x, save=None)

Plots the density of df[str_x].

Parameters:

Name Type Description Default
df DataFrame

the data with the str_x variable

required
str_x str

the name of a continuous column

required
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_density(df: pd.DataFrame, str_x: str, save: str | None = None) -> alt.Chart:
    """Plots the density of `df[str_x]`.

    Args:
        df: the data with the `str_x` variable
        str_x: the name of a continuous column
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    ch = (
        alt.Chart(df)
        .transform_density(
            str_x,
            as_=[str_x, "Density"],
        )
        .mark_area(opacity=0.4)
        .encode(
            x=f"{str_x}:Q",
            y="Density:Q",
        )
    )

    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_faceted_densities(df, str_x, str_f, legend_title=None, save=None, max_cols=4)

Plots the density of df[str_x] by df[str_f] in column facets

Parameters:

Name Type Description Default
df DataFrame

the data with the str_x and str_f variables

required
str_x str

the name of a continuous column

required
str_f str

the name of a categorical column

required
legend_title str | None

a title for the legend

None
save str | None

the name of a file to save to (HTML extension will be added)

None
max_cols int | None

we wrap after that number of columns

4

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_faceted_densities(
    df: pd.DataFrame,
    str_x: str,
    str_f: str,
    legend_title: str | None = None,
    save: str | None = None,
    max_cols: int | None = 4,
) -> alt.Chart:
    """
    Plots the density of `df[str_x]` by `df[str_f]` in column facets

    Args:
        df: the data with the `str_x` and `str_f` variables
        str_x: the name of a continuous column
        str_f: the name of a categorical column
        legend_title: a title for the legend
        save: the name of a file to save to (HTML extension will be added)
        max_cols: we wrap after that number of columns

    Returns:
        the `alt.Chart` object.
    """
    our_legend_title = str_f if legend_title is None else legend_title
    ch = (
        alt.Chart(df)
        .transform_density(
            str_x,
            groupby=[str_f],
            as_=[str_x, "Density"],
        )
        .mark_area(opacity=0.4)
        .encode(
            x=f"{str_x}:Q",
            y="Density:Q",
            color=alt.Color(f"{str_f}:N", title=our_legend_title),
        )
        .facet(f"{str_f}:N", columns=max_cols)
    )

    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_histogram_by(df, str_x, str_y, str_agg='mean', save=None)

Plots a histogram of a statistic of str_y by str_x

Parameters:

Name Type Description Default
df DataFrame

a dataframe with columns str_x and str_y

required
str_x str

a categorical variable

required
str_y str

a continuous variable

required
str_agg str | None

how we aggregate the values of str_y by str_x

'mean'
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the Altair chart.

Source code in bs_python_utils/bs_altair.py
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def alt_histogram_by(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    str_agg: str | None = "mean",
    save: str | None = None,
) -> alt.Chart:
    """
    Plots a histogram of a statistic of `str_y` by `str_x`

    Args:
        df: a dataframe with columns `str_x` and `str_y`
        str_x: a categorical variable
        str_y: a continuous variable
        str_agg: how we aggregate the values of `str_y` by `str_x`
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the Altair chart.
    """
    ch = (
        alt.Chart(df)
        .mark_bar()
        .encode(x=str_x, y=f"{str_agg}({str_y}):Q")
        .properties(height=300, width=400)
    )
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_histogram_continuous(df, str_x, save=None)

Histogram of a continuous variable df[str_x]

Parameters:

Name Type Description Default
df DataFrame

the data with the str_x, str_y, and str_f variables

required
str_x str

the name of a continuous column

required
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_histogram_continuous(
    df: pd.DataFrame, str_x: str, save: str | None = None
) -> alt.Chart:
    """
    Histogram of a continuous variable `df[str_x]`

    Args:
        df: the data with the `str_x`, `str_y`, and `str_f` variables
        str_x: the name of a continuous column
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    ch = alt.Chart(df).mark_bar().encode(alt.X(str_x, bin=True), y="count()")
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_lineplot(df, str_x, str_y, time_series=False, save=None, aggreg=None, **kwargs)

Scatterplot of df[str_x] vs df[str_y]

Parameters:

Name Type Description Default
df DataFrame

the data with columns str_x and str_y

required
str_x str

the name of a continuous column

required
str_y str

the name of a continuous column

required
time_series bool

True if x is a time series

False
save str | None

the name of a file to save to (HTML extension will be added)

None
aggreg str | None

the name of an aggregating function for y

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_lineplot(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    time_series: bool = False,
    save: str | None = None,
    aggreg: str | None = None,
    **kwargs,
) -> alt.Chart:
    """
    Scatterplot of `df[str_x]` vs `df[str_y]`

    Args:
        df: the data with columns `str_x` and `str_y`
        str_x: the name of a continuous column
        str_y: the name of a continuous column
        time_series: `True` if x is a time series
        save: the name of a file to save to (HTML extension will be added)
        aggreg: the name of an aggregating function for `y`

    Returns:
        the `alt.Chart` object.
    """
    type_x = "T" if time_series else "Q"
    var_y = f"{aggreg}({str_y}):Q" if aggreg is not None else str_y

    ch = alt.Chart(df).mark_line().encode(x=f"{str_x}:{type_x}", y=var_y)
    if "title" in kwargs:
        ch = ch.properties(title=kwargs["title"])
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_linked_scatterplots(df, str_x1, str_x2, str_y, str_f, save=None)

Creates two scatterplots: of df[str_x1] vs df[str_y] and of df[str_x2] vs df[str_y], both with color as per df[str_f]. Selecting an interval in one shows up in the other.

Parameters:

Name Type Description Default
df DataFrame
required
str_x1 str

the name of a continuous column

required
str_x2 str

the name of a continuous column

required
str_y str

the name of a continuous column

required
str_f str

the name of a categorical column

required
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_linked_scatterplots(
    df: pd.DataFrame,
    str_x1: str,
    str_x2: str,
    str_y: str,
    str_f: str,
    save: str | None = None,
) -> alt.Chart:
    """
    Creates two scatterplots: of `df[str_x1]` vs `df[str_y]` and of
    `df[str_x2]` vs `df[str_y]`,
    both with color as per `df[str_f]`. Selecting an interval in one shows up
    in the other.

    Args:
        df:
        str_x1: the name of a continuous column
        str_x2: the name of a continuous column
        str_y: the name of a continuous column
        str_f: the name of a categorical column
        save: the name of a file to save to (HTML extension will be added)

    Returns:
          the `alt.Chart` object.
    """
    interval = alt.selection_interval()

    base = (
        alt.Chart(df)
        .mark_point()
        .encode(
            y=f"{str_y}:Q", color=alt.condition(interval, str_f, alt.value("lightgray"))
        )
        .add_params(interval)
    )

    ch = base.encode(x=f"{str_x1}:Q") | base.encode(x=f"{str_x2}:Q")

    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_matrix_heatmap(mat, str_format, multiple=1.0, title=None, str_rows='Row', str_cols='Column', save=None)

Plot a matrix heatmap using circle size and text annotations.

Parameters:

Name Type Description Default
mat ndarray

Matrix to visualise; converted to a long-form data frame internally.

required
str_format str

Format specifier for the textual values (e.g. "d" or ".2f").

required
multiple float

Multiplier applied to the circle size scale.

1.0
title str | None

Optional chart title.

None
str_rows str | None

Label used for the row coordinate in the long-form frame.

'Row'
str_cols str | None

Label used for the column coordinate in the long-form frame.

'Column'
save str | None

Optional basename to save the chart as HTML.

None

Returns:

Type Description
Chart

The Altair Chart showing the heatmap.

Source code in bs_python_utils/bs_altair.py
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def alt_matrix_heatmap(
    mat: np.ndarray,
    str_format: str,
    multiple: float = 1.0,
    title: str | None = None,
    str_rows: str | None = "Row",
    str_cols: str | None = "Column",
    save: str | None = None,
) -> alt.Chart:
    """Plot a matrix heatmap using circle size and text annotations.

    Args:
        mat: Matrix to visualise; converted to a long-form data frame internally.
        str_format: Format specifier for the textual values (e.g. ``"d"`` or ``".2f"``).
        multiple: Multiplier applied to the circle size scale.
        title: Optional chart title.
        str_rows: Label used for the row coordinate in the long-form frame.
        str_cols: Label used for the column coordinate in the long-form frame.
        save: Optional basename to save the chart as HTML.

    Returns:
        The Altair ``Chart`` showing the heatmap.
    """
    n_rows, n_cols = check_matrix(mat)
    mat_df = (
        pd.DataFrame(mat)
        .stack()
        .rename_axis([str_rows, str_cols])
        .reset_index(name="Value")
    )
    if "d" in str_format:
        mat_df["Value"] = mat_df["Value"].round().astype(int)
    mat_min = mat_df["Value"].min()
    mat_df["Size"] = (mat_df["Value"] - mat_min + 1).astype(float)
    base = alt.Chart(mat_df).encode(
        x=f"{str_rows}:O", y=alt.Y(f"{str_cols}:O", sort="descending")
    )
    mat_map = base.mark_circle(opacity=0.4).encode(
        size=alt.Size(
            "Size:Q",
            legend=None,
            scale=alt.Scale(range=[1000 * multiple, 10000 * multiple]),
        )
    )
    text = base.mark_text(baseline="middle", fontSize=16).encode(
        text=alt.Text("Value:Q", format=str_format),
    )
    if title is None:
        both = (mat_map + text).properties(width=500, height=500)
    else:
        both = (mat_map + text).properties(title=title, width=400, height=400)

    _maybe_save(both, save)
    return cast(alt.Chart, both)

alt_plot_fun(f, start, end, npoints=100, save=None)

Plot the scalar function f on [start, end] using npoints samples.

Parameters:

Name Type Description Default
f Callable

Callable mapping a NumPy array of x-values to an array of y-values.

required
start float

Lower bound of the plotting interval.

required
end float

Upper bound of the plotting interval.

required
npoints int

Number of sampling points (generated with np.linspace).

100
save str | None

Optional basename to save the chart as HTML.

None

Returns:

Type Description
Chart

The Altair Chart for further composition or rendering.

Source code in bs_python_utils/bs_altair.py
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def alt_plot_fun(
    f: Callable,
    start: float,
    end: float,
    npoints: int = 100,
    save: str | None = None,
) -> alt.Chart:
    """Plot the scalar function ``f`` on ``[start, end]`` using ``npoints`` samples.

    Args:
        f: Callable mapping a NumPy array of x-values to an array of y-values.
        start: Lower bound of the plotting interval.
        end: Upper bound of the plotting interval.
        npoints: Number of sampling points (generated with ``np.linspace``).
        save: Optional basename to save the chart as HTML.

    Returns:
        The Altair ``Chart`` for further composition or rendering.
    """
    points = np.linspace(start, end, num=npoints)
    fun_data = pd.DataFrame({"x": points, "y": f(points)})

    ch = (
        alt.Chart(fun_data)
        .mark_line()
        .encode(
            x="x:Q",
            y="y:Q",
        )
    )

    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_scatterplot(df, str_x, str_y, time_series=False, save=None, xlabel=None, ylabel=None, size=30, title=None, color=None, aggreg=None, selection=False)

Scatter df[str_y] against df[str_x] with optional coloring/selection.

Parameters:

Name Type Description Default
df DataFrame

Data frame holding the features to plot.

required
str_x str

Column name for the horizontal axis (continuous or time series).

required
str_y str

Column name for the vertical axis (continuous).

required
time_series bool

If True encodes the x-axis as temporal.

False
save str | None

Optional basename to save the chart as HTML.

None
xlabel str | None

Optional label for the x-axis; must be a string when provided.

None
ylabel str | None

Optional label for the y-axis; must be a string when provided.

None
size int | None

Marker size (integer radius in pixels).

30
title str | None

Optional chart title.

None
color str | None

Column used for color encoding.

None
aggreg str | None

Optional aggregation function for str_y (e.g. "mean").

None
selection bool

When True and a color is supplied, enable legend-based multi-selection.

False

Returns:

Type Description
Chart

The Altair Chart for further composition or rendering.

Source code in bs_python_utils/bs_altair.py
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def alt_scatterplot(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    time_series: bool = False,
    save: str | None = None,
    xlabel: str | None = None,
    ylabel: str | None = None,
    size: int | None = 30,
    title: str | None = None,
    color: str | None = None,
    aggreg: str | None = None,
    selection: bool = False,
) -> alt.Chart:
    """Scatter ``df[str_y]`` against ``df[str_x]`` with optional coloring/selection.

    Args:
        df: Data frame holding the features to plot.
        str_x: Column name for the horizontal axis (continuous or time series).
        str_y: Column name for the vertical axis (continuous).
        time_series: If ``True`` encodes the x-axis as temporal.
        save: Optional basename to save the chart as HTML.
        xlabel: Optional label for the x-axis; must be a string when provided.
        ylabel: Optional label for the y-axis; must be a string when provided.
        size: Marker size (integer radius in pixels).
        title: Optional chart title.
        color: Column used for color encoding.
        aggreg: Optional aggregation function for ``str_y`` (e.g. ``"mean"``).
        selection: When ``True`` and a ``color`` is supplied, enable
            legend-based multi-selection.

    Returns:
        The Altair ``Chart`` for further composition or rendering.
    """
    type_x = "T" if time_series else "Q"
    var_x = alt.X(f"{str_x}:{type_x}")

    if xlabel is not None:
        if not isinstance(xlabel, str):
            raise TypeError(f"xlabel must be a string, not {xlabel!r}")
        var_x = alt.X(f"{str_x}:{type_x}", axis=alt.Axis(title=xlabel))

    var_y = f"{aggreg}({str_y}):Q" if aggreg is not None else str_y
    y_encoding: alt.Y | str

    if ylabel is not None:
        if not isinstance(ylabel, str):
            raise TypeError(f"ylabel must be a string, not {ylabel!r}")
        y_encoding = alt.Y(var_y, axis=alt.Axis(title=ylabel))
    else:
        y_encoding = var_y

    if not isinstance(size, int):
        raise TypeError(f"size must be an integer, not {size!r}")
    circles_size = size

    if color is not None:
        if not isinstance(color, str):
            raise TypeError(f"color must be a string, not {color!r}")
        if selection:
            selection_criterion = alt.selection_multi(fields=[color], bind="legend")
            ch = (
                alt.Chart(df)
                .mark_circle(size=circles_size)
                .encode(
                    x=var_x,
                    y=y_encoding,
                    color=color,
                    opacity=alt.condition(
                        selection_criterion, alt.value(1), alt.value(0.1)
                    ),
                )
                .add_params(selection_criterion)
            )
        else:
            ch = (
                alt.Chart(df)
                .mark_circle(size=circles_size)
                .encode(x=var_x, y=y_encoding, color=color)
            )
    else:
        ch = alt.Chart(df).mark_circle(size=circles_size).encode(x=var_x, y=y_encoding)

    ch = _add_title(ch, title)
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_scatterplot_with_histo(df, str_x, str_y, str_f, save=None)

Scatterplot of df[str_x] vs df[str_y] with colors as per df[str_f] allows to select an interval and histograns the counts of df[str_f] in the interval.

Parameters:

Name Type Description Default
df DataFrame

the data with the str_x and str_f variables

required
str_x str

the name of a continuous column

required
str_y str

the name of a continuous column

required
str_f str

the name of a categorical column

required
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_scatterplot_with_histo(
    df: pd.DataFrame, str_x: str, str_y: str, str_f: str, save: str | None = None
) -> alt.Chart:
    """
    Scatterplot of `df[str_x]` vs `df[str_y]` with colors as per `df[str_f]`
    allows to select an interval and histograns the counts of `df[str_f]` in
    the interval.

    Args:
        df: the data with the `str_x` and `str_f` variables
        str_x: the name of a continuous column
        str_y: the name of a continuous column
        str_f: the name of a categorical column
        save: the name of a file to save to (HTML extension will be added)

    Returns:
          the `alt.Chart` object.
    """
    interval = alt.selection_interval()

    points = (
        alt.Chart(df)
        .mark_point()
        .encode(
            x=f"{str_x}:Q",
            y=f"{str_y}:Q",
            color=alt.condition(interval, str_f, alt.value("lightgray")),
        )
        .add_params(interval)
    )

    histogram = (
        alt.Chart(df)
        .mark_bar()
        .encode(
            x="count()",
            y=str_f,
            color=str_f,
        )
        .transform_filter(interval)
    )

    ch = points & histogram

    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_stacked_area(df, str_x, str_y, str_f, time_series=False, title=None, save=None)

Normalized stacked lineplots of df[str_x] vs df[str_y] by df[str_f]

Parameters:

Name Type Description Default
df DataFrame

the data with columns for str_x, str_y, and str_f

required
str_x str

the name of a continuous column

required
str_y str

the name of a continuous column

required
str_f str

the name of a categorical column

required
time_series bool

True if str_x is a time series

False
title str | None

a title for the plot

None
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_stacked_area(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    str_f: str,
    time_series: bool = False,
    title: str | None = None,
    save: str | None = None,
) -> alt.Chart:
    """
    Normalized stacked lineplots of `df[str_x]` vs `df[str_y]` by `df[str_f]`

    Args:
        df: the data with columns for `str_x`, `str_y`, and `str_f`
        str_x: the name of a continuous column
        str_y: the name of a continuous column
        str_f: the name of a categorical column
        time_series: `True` if `str_x` is a time series
        title: a title for the plot
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    type_x = "T" if time_series else "Q"
    ch = (
        alt.Chart(df)
        .mark_area()
        .encode(
            x=f"{str_x}:{type_x}",
            y=alt.Y(f"{str_y}:Q", stack="normalize"),
            color=f"{str_f}:N",
        )
    )
    if title is not None:
        ch = ch.properties(title=title)

    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_stacked_area_facets(df, str_x, str_y, str_f, str_g, time_series=False, max_cols=5, title=None, save=None)

Normalized stacked lineplots of df[str_x] vs df[str_y] by df[str_f], faceted by df[str_g]

Parameters:

Name Type Description Default
df DataFrame

the data with columns for str_x, str_y, and str_f

required
str_x str

the name of a continuous column

required
str_y str

the name of a continuous column

required
str_f str

the name of a categorical column

required
str_g str

the name of a categorical column

required
time_series bool

True if str_x is a time series

False
title str | None

a title for the plot

None
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_stacked_area_facets(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    str_f: str,
    str_g: str,
    time_series: bool = False,
    max_cols: int | None = 5,
    title: str | None = None,
    save: str | None = None,
) -> alt.Chart:
    """
    Normalized stacked lineplots of `df[str_x]` vs `df[str_y]` by `df[str_f]`,
    faceted by `df[str_g]`

    Args:
        df: the data with columns for `str_x`, `str_y`, and `str_f`
        str_x: the name of a continuous column
        str_y: the name of a continuous column
        str_f: the name of a categorical column
        str_g: the name of a categorical column
        time_series: `True` if `str_x` is a time series
        title: a title for the plot
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    type_x = "T" if time_series else "Q"
    ch = (
        alt.Chart(df)
        .mark_area()
        .encode(
            x=f"{str_x}:{type_x}",
            y=alt.Y(f"{str_y}:Q", stack="normalize"),
            color=f"{str_f}:N",
            facet=(
                alt.Facet(f"{str_g}:N", columns=max_cols)
                if max_cols is not None
                else alt.Facet(f"{str_g}:N")
            ),
        )
    )
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_superposed_faceted_densities(df, str_x, str_f, str_g, max_cols=4, save=None)

Creates density plots of df[str_x] by df[str_f] and df[str_g] with color as per df[str_f] and faceted by df[str_g]. that is: facets by str_g, with densities conditional on str_f superposed.

Parameters:

Name Type Description Default
df DataFrame

a Pandas dataframe wity columns str_x, str_f, str_g

required
str_x str

the name of a continuous column

required
str_f str

the name of a categorical column

required
str_g str

the name of a categorical column

required
max_cols int | None

the number of columns after whcih we wrap

4
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_superposed_faceted_densities(
    df: pd.DataFrame,
    str_x: str,
    str_f: str,
    str_g: str,
    max_cols: int | None = 4,
    save: str | None = None,
) -> alt.Chart:
    """
    Creates density plots of `df[str_x]` by `df[str_f]` and `df[str_g]`
    with color as per `df[str_f]` and faceted by `df[str_g]`.
    that is: facets by `str_g`, with densities conditional on `str_f` superposed.

    Args:
        df: a Pandas dataframe wity columns `str_x`, `str_f`, `str_g`
        str_x: the name of a continuous column
        str_f: the name of a categorical column
        str_g: the name of a categorical column
        max_cols: the number of columns after whcih we wrap
        save: the name of a file to save to (HTML extension will be added)

    Returns:
          the `alt.Chart` object.
    """
    densities = (
        alt.Chart(df)
        .transform_density(
            str_x,
            groupby=[str_f, str_g],
            as_=[str_x, "Density"],
        )
        .mark_line()
        .encode(
            x=f"{str_x}:Q",
            y="Density:Q",
            color=f"{str_f}:N",
        )
        .facet(column=f"{str_g}:N", columns=max_cols)
        .resolve_scale(x="independent", y="independent")
    )
    _maybe_save(densities, save)

    return cast(alt.Chart, densities)

alt_superposed_faceted_lineplot(df, str_x, str_y, str_f, str_g, time_series=False, legend_title=None, max_cols=5, save=None)

Plots df[str_x] vs df[str_y] superposed by df[str_f] and faceted by df[str_g]

Parameters:

Name Type Description Default
df DataFrame

the data with the str_x, str_y, and str_f variables

required
str_x str

the name of a continuous column

required
str_y str

the name of a continuous column

required
str_f str

the name of a categorical column

required
str_g str

the name of a categorical column

required
time_series bool

True if str_x is a time series

False
legend_title str | None

a title for the legend

None
save str | None

the name of a file to save to (HTML extension will be added)

None
max_cols int | None

we wrap after that number of columns

5

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_superposed_faceted_lineplot(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    str_f: str,
    str_g: str,
    time_series: bool = False,
    legend_title: str | None = None,
    max_cols: int | None = 5,
    save: str | None = None,
) -> alt.Chart:
    """
    Plots `df[str_x]` vs `df[str_y]` superposed by `df[str_f]` and faceted by
    `df[str_g]`

    Args:
        df: the data with the `str_x`, `str_y`, and `str_f` variables
        str_x: the name of a continuous column
        str_y: the name of a continuous column
        str_f: the name of a categorical column
        str_g: the name of a categorical column
        time_series: `True` if `str_x` is a time series
        legend_title: a title for the legend
        save: the name of a file to save to (HTML extension will be added)
        max_cols: we wrap after that number of columns


    Returns:
        the `alt.Chart` object.
    """
    type_x = "T" if time_series else "Q"
    our_title = str_f if legend_title is None else legend_title
    ch = (
        alt.Chart(df)
        .mark_line()
        .encode(
            x=f"{str_x}:{type_x}",
            y=f"{str_y}:Q",
            color=alt.Color(f"{str_f}:N", title=our_title),
            facet=(
                alt.Facet(f"{str_g}:N", columns=max_cols)
                if max_cols is not None
                else alt.Facet(f"{str_g}:N")
            ),
        )
    )
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_superposed_lineplot(df, str_x, str_y, str_f, time_series=False, legend_title=None, save=None)

Plots df[str_x] vs df[str_y] by df[str_f] on one plot

Parameters:

Name Type Description Default
df DataFrame

the data with the str_x, str_y, and str_f variables

required
str_x str

the name of a continuous x column

required
str_y str

the name of a continuous y column

required
str_f str

the name of a categorical f column

required
time_series bool

True if str_x is a time series

False
legend_title str | None

a title for the legend

None
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_superposed_lineplot(
    df: pd.DataFrame,
    str_x: str,
    str_y: str,
    str_f: str,
    time_series: bool = False,
    legend_title: str | None = None,
    save: str | None = None,
) -> alt.Chart:
    """
    Plots `df[str_x]` vs `df[str_y]` by `df[str_f]` on one plot

    Args:
        df: the data with the `str_x`, `str_y`, and `str_f` variables
        str_x: the name of a continuous `x` column
        str_y: the name of a continuous `y` column
        str_f: the name of a categorical `f` column
        time_series: `True` if `str_x` is a time series
        legend_title: a title for the legend
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    type_x = "T" if time_series else "Q"
    our_legend_title = str_f if legend_title is None else legend_title
    ch = (
        alt.Chart(df)
        .mark_line()
        .encode(
            x=f"{str_x}:{type_x}",
            y=f"{str_y}:Q",
            color=alt.Color(f"{str_f}:N", title=our_legend_title),
        )
    )
    _maybe_save(ch, save)
    return cast(alt.Chart, ch)

alt_tick_plots(df, list_vars, save=None)

Creates a tick plot of the variables in list_vars ofdf, arranged vertically.

Parameters:

Name Type Description Default
df DataFrame

a dataframe with the variables in list_vars

required
list_vars str | list[str]

the name of a column of df, or a list of names

required
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def alt_tick_plots(
    df: pd.DataFrame, list_vars: str | list[str], save: str | None = None
) -> alt.Chart:
    """
    Creates a tick plot of the variables in `list_vars` of`df`, arranged vertically.

    Args:
        df: a dataframe with the variables in `list_vars`
        list_vars: the name of a column of `df`, or a list of names
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    if isinstance(list_vars, str):
        varname = list_vars
        ch = alt.Chart(df).encode(x=varname).mark_tick()
    else:
        ch = (
            alt.Chart(df)
            .encode(alt.X(alt.repeat("row"), type="quantitative"))
            .mark_tick()
            .repeat(row=list_vars)
            .resolve_scale(y="independent")
        )

    _maybe_save(ch, save)

    return cast(alt.Chart, ch)

plot_parameterized_estimates(parameter_name, parameter_values, coeff_names, true_values, estimate_names, estimates, colors, save=None)

Plots estimates of coefficients, with the true values, as a function of a parameter; one facet per coefficient

Parameters:

Name Type Description Default
parameter_name str

the name of the parameter

required
parameter_values ndarray

a vector of n_vals values for the parameter

required
coeff_names str | list[str]

the names of the n_coeffs coefficients

required
true_values ndarray

their true values, depending on the parameter or not

required
estimate_names str | list[str]

names of the estimates

required
estimates ndarray

their values

required
colors list[str]

colors for the various estimates

required
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def plot_parameterized_estimates(
    parameter_name: str,
    parameter_values: np.ndarray,
    coeff_names: str | list[str],
    true_values: np.ndarray,
    estimate_names: str | list[str],
    estimates: np.ndarray,
    colors: list[str],
    save: str | None = None,
) -> alt.Chart:
    """
    Plots estimates of coefficients, with the true values, as a function of a
    parameter; one facet per coefficient

    Args:
        parameter_name: the name of the parameter
        parameter_values: a vector of `n_vals` values for the parameter
        coeff_names: the names of the `n_coeffs` coefficients
        true_values: their true values, depending on the parameter or not
        estimate_names: names of the estimates
        estimates: their values
        colors: colors for the various estimates
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    n_vals = check_vector(parameter_values)
    n_coeffs = 1 if isinstance(coeff_names, str) else len(coeff_names)
    if n_coeffs == 1:
        n_true = check_vector(true_values, "plot_parameterized_estimates")
        if n_true != n_vals:
            bs_error_abort(
                f"plot_parameterized_estimates: we have {n_true} values and"
                f" {n_vals} parameter values."
            )
        df = pd.DataFrame({parameter_name: parameter_values, "True value": true_values})
        df1, ordered_estimates = _stack_estimates(estimate_names, estimates, df)
        df1m = pd.melt(df1, parameter_name, var_name="Estimate")
        ch = (
            alt.Chart(df1m)
            .mark_line()
            .encode(
                x=f"{parameter_name}:Q",
                y="value:Q",
                strokeDash=alt.StrokeDash("Estimate:N", sort=ordered_estimates),
                color=alt.Color(
                    "Estimate:N",
                    sort=estimate_names,
                    scale=alt.Scale(domain=ordered_estimates, range=colors),
                ),
            )
        )
    else:
        n_true, n_c = check_matrix(true_values, "plot_parameterized_estimates")
        if n_true != n_vals:
            bs_error_abort(
                f"plot_parameterized_estimates: we have {n_true} true values and"
                f" {n_vals} parameter values."
            )
        if n_c != n_coeffs:
            bs_error_abort(
                f"plot_parameterized_estimates: we have {n_c} columns of true values"
                f" and {n_coeffs} coefficients."
            )
        df1 = [None] * n_coeffs
        for i_coeff, coeff in enumerate(coeff_names):
            df_i = pd.DataFrame(
                {
                    parameter_name: parameter_values,
                    "True value": true_values[:, i_coeff],
                }
            )
            df1[i_coeff], ordered_estimates = _stack_estimates(
                estimate_names, estimates[..., i_coeff], df_i
            )
            df1[i_coeff]["Coefficient"] = coeff

        df2 = pd.concat(df1[i_coeff] for i_coeff in range(n_coeffs))
        ordered_colors = colors
        df2m = pd.melt(df2, [parameter_name, "Coefficient"], var_name="Estimate")
        ch = (
            alt.Chart(df2m)
            .mark_line()
            .encode(
                x=f"{parameter_name}:Q",
                y="value:Q",
                strokeDash=alt.StrokeDash("Estimate:N", sort=ordered_estimates),
                color=alt.Color(
                    "Estimate:N",
                    sort=ordered_estimates,
                    scale=alt.Scale(domain=ordered_estimates, range=ordered_colors),
                ),
            )
            .facet(alt.Facet("Coefficient:N", sort=coeff_names))
            .resolve_scale(y="independent")
        )

    _maybe_save(ch, save)

    return cast(alt.Chart, ch)

plot_true_sim2_facets(parameter_name, parameter_values, stat_names, stat_true, stat_sim1, stat_sim2, colors, stat_title='Statistic', subtitle='True vs estimated', ncols=3, save=None)

Plots simulated values for two methods and true values of statistics as a function of a parameter; one facet per coefficient

Parameters:

Name Type Description Default
parameter_name str

the name of the parameter

required
parameter_values ndarray

a vector of n_vals values for the parameter

required
stat_names list[str]

the names of the n statistics

required
stat_true ndarray

their true values, (n_vals, n)

required
stat_sim1 ndarray

their simulated values, method 1

required
stat_sim2 ndarray

their simulated values, method 2

required
colors list[str]

colors for the various estimates

required
stat_title str | None

main title

'Statistic'
subtitle str | None

subtitle

'True vs estimated'
ncols int | None

wrap after ncols columns

3
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def plot_true_sim2_facets(
    parameter_name: str,
    parameter_values: np.ndarray,
    stat_names: list[str],
    stat_true: np.ndarray,
    stat_sim1: np.ndarray,
    stat_sim2: np.ndarray,
    colors: list[str],
    stat_title: str | None = "Statistic",
    subtitle: str | None = "True vs estimated",
    ncols: int | None = 3,
    save: str | None = None,
) -> alt.Chart:
    """
    Plots simulated values for two methods and true values of statistics as a
    function of a parameter;
    one facet per coefficient

    Args:
        parameter_name: the name of the parameter
        parameter_values: a vector of `n_vals` values for the parameter
        stat_names: the names of the `n` statistics
        stat_true: their true values, `(n_vals, n)`
        stat_sim1: their simulated values, method 1
        stat_sim2: their simulated values, method 2
        colors: colors for the various estimates
        stat_title: main title
        subtitle: subtitle
        ncols: wrap after `ncols` columns
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    n_stats = len(stat_names)
    nvals = check_vector(parameter_values, "plot_true_sim2_facets")
    nv_true, n_stat_true = check_matrix(stat_true, "plot_true_sim2_facets")
    if nv_true != nvals:
        bs_error_abort(f"we have {nvals} parameter values and {nv_true} for stat_true.")
    if n_stat_true != n_stats:
        bs_error_abort(f"we have {n_stats} names for {n_stat_true} true statistics.")

    nv_est1, n_stat_est1 = check_matrix(stat_sim1, "plot_true_sim2_facets")
    if nv_est1 != nvals:
        bs_error_abort(f"we have {nvals} parameter values and {nv_est1} for stat_sim1.")
    if n_stat_est1 != n_stats:
        bs_error_abort(
            f"we have {n_stats} names for {n_stat_est1} estimated statistics."
        )
    nv_est2, n_stat_est2 = check_matrix(stat_sim2, "plot_true_sim2_facets")
    if nv_est2 != nvals:
        bs_error_abort(f"we have {nvals} parameter values and {nv_est2} for stat_sim2.")
    if n_stat_est2 != n_stats:
        bs_error_abort(
            f"we have {n_stats} names for {n_stat_est2} estimated statistics."
        )

    df = pd.DataFrame(
        {
            parameter_name: parameter_values,
            "True value": stat_true[:, 0],
            "Estimated1": stat_sim1[:, 0],
            "Estimated2": stat_sim2[:, 0],
            stat_title: stat_names[0],
        }
    )
    for i_stat in range(1, n_stats):
        df_i = pd.DataFrame(
            {
                parameter_name: parameter_values,
                "True value": stat_true[:, i_stat],
                "Estimated1": stat_sim1[:, i_stat],
                "Estimated2": stat_sim2[:, i_stat],
                stat_title: stat_names[i_stat],
            }
        )
        df = pd.concat((df, df_i))
    sub_order = ["True value", "Estimated1", "Estimated2"]
    dfm = pd.melt(df, [parameter_name, stat_title], var_name=subtitle)
    ch = (
        alt.Chart(dfm)
        .mark_line()
        .encode(
            x=f"{parameter_name}:Q",
            y="value:Q",
            strokeDash=alt.StrokeDash(f"{subtitle}:N", sort=sub_order),
            color=alt.Color(
                f"{subtitle}:N",
                sort=sub_order,
                scale=alt.Scale(domain=sub_order, range=colors),
            ),
            facet=(
                alt.Facet(f"{stat_title}:N", sort=stat_names, columns=ncols)
                if ncols is not None
                else alt.Facet(f"{stat_title}:N", sort=stat_names)
            ),
        )
        .resolve_scale(y="independent")
    )

    _maybe_save(ch, save)

    return cast(alt.Chart, ch)

plot_true_sim_facets(parameter_name, parameter_values, stat_names, stat_true, stat_sim, colors, stat_title='Statistic', subtitle='True vs estimated', ncols=3, save=None)

Plots simulated and true values of statistics as a function of a parameter; one facet per coefficient

Parameters:

Name Type Description Default
parameter_name str

the name of the parameter

required
parameter_values ndarray

a vector of n_vals values for the parameter

required
stat_names list[str]

the names of the n statistics

required
stat_true ndarray

their true values, (n_vals, n)

required
stat_sim ndarray

their simulated values

required
colors list[str]

colors for the various estimates

required
stat_title str | None

main title

'Statistic'
subtitle str | None

subtitle

'True vs estimated'
ncols int | None

wrap after ncols columns

3
save str | None

the name of a file to save to (HTML extension will be added)

None

Returns:

Type Description
Chart

the alt.Chart object.

Source code in bs_python_utils/bs_altair.py
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def plot_true_sim_facets(
    parameter_name: str,
    parameter_values: np.ndarray,
    stat_names: list[str],
    stat_true: np.ndarray,
    stat_sim: np.ndarray,
    colors: list[str],
    stat_title: str | None = "Statistic",
    subtitle: str | None = "True vs estimated",
    ncols: int | None = 3,
    save: str | None = None,
) -> alt.Chart:
    """
    Plots simulated and true values of statistics as a function of a parameter;
    one facet per coefficient

    Args:
        parameter_name: the name of the parameter
        parameter_values: a vector of `n_vals` values for the parameter
        stat_names: the names of the `n` statistics
        stat_true: their true values, `(n_vals, n)`
        stat_sim: their simulated values
        colors: colors for the various estimates
        stat_title: main title
        subtitle: subtitle
        ncols: wrap after `ncols` columns
        save: the name of a file to save to (HTML extension will be added)

    Returns:
        the `alt.Chart` object.
    """
    n_stats = len(stat_names)
    nvals = check_vector(parameter_values, "plot_true_sim_facets")
    nv_true, n_stat_true = check_matrix(stat_true, "plot_true_sim_facets")
    if nv_true != nvals:
        bs_error_abort(
            f"plot_true_sim_facets: we have {nvals} parameter values and {nv_true} for"
            " stat_true."
        )
    nv_est, n_stat_est = check_matrix(stat_sim, "plot_true_sim_facets")
    if nv_est != nvals:
        bs_error_abort(
            f"plot_true_sim_facets: we have {nvals} parameter values and {nv_est} for"
            " stat_sim."
        )
    if n_stat_true != n_stats:
        bs_error_abort(
            f"plot_true_sim_facets: we have {n_stats} names for {n_stat_true} true"
            " statistics."
        )
    if n_stat_est != n_stats:
        bs_error_abort(
            f"plot_true_sim_facets: we have {n_stats} names for {n_stat_est} estimated"
            " statistics."
        )
    df = pd.DataFrame(
        {
            parameter_name: parameter_values,
            "True value": stat_true[:, 0],
            "Estimated": stat_sim[:, 0],
            stat_title: stat_names[0],
        }
    )
    for i_stat in range(1, n_stats):
        df_i = pd.DataFrame(
            {
                parameter_name: parameter_values,
                "True value": stat_true[:, i_stat],
                "Estimated": stat_sim[:, i_stat],
                stat_title: stat_names[i_stat],
            }
        )
        df = pd.concat((df, df_i))
    sub_order = ["True value", "Estimated"]
    dfm = pd.melt(df, [parameter_name, stat_title], var_name=subtitle)
    ch = (
        alt.Chart(dfm)
        .mark_line()
        .encode(
            x=f"{parameter_name}:Q",
            y="value:Q",
            strokeDash=alt.StrokeDash(f"{subtitle}:N", sort=sub_order),
            color=alt.Color(
                f"{subtitle}:N",
                sort=sub_order,
                scale=alt.Scale(domain=sub_order, range=colors),
            ),
            facet=(
                alt.Facet(f"{stat_title}:N", sort=stat_names, columns=ncols)
                if ncols is not None
                else alt.Facet(f"{stat_title}:N", sort=stat_names)
            ),
        )
        .resolve_scale(y="independent")
    )

    _maybe_save(ch, save)

    return cast(alt.Chart, ch)