Imports name this capability’s declared dependencies, which fune builds next to it in your project; each one links to its page.
from .charts_axis_band_axis import band_axis
from .charts_axis_grid_lines import grid_lines
from .charts_axis_number_axis import number_axis
from .charts_bar_chart_types import BarChart, BarChartSpec, ChartBar
from .charts_format_format_tick import format_tick
from .charts_layout_legend_rows import legend_rows
from .charts_layout_plot_area import plot_area
from .charts_layout_types import LegendItem, Margins
from .charts_palette import palette ← from charts.palette ^1.0.0 · built alongside by fune
from .charts_scale_band_scale import band_scale
from .charts_scale_linear_scale import linear_scale
from .charts_scale_nice_domain import nice_domain
from .charts_shape_bar_rects import bar_rects
from .charts_shape_types import BarSpec
from .charts_stack import stack ← from charts.stack ^1.0.0 · built alongside by fune
from .charts_ticks_nice_ticks import nice_ticks
from .charts_ticks_tick_step import tick_step
from .math_round_float import round_float ← from math.round-float ^1.0.0 · built alongside by fune
# Fixed layout constants; the README explains each.
CHAR_WIDTH = 7
SWATCH = 10
LEGEND_GAP = 16
LEGEND_ROW = 18
EDGE = 8
TICK_SIZE = 6
LABEL_PADDING = 3
TOP_WITHOUT_LEGEND = 12
RIGHT = 20
BOTTOM = 30
CATEGORY_PADDING_INNER = 0.2
CATEGORY_PADDING_OUTER = 0.1
SERIES_PADDING = 0.05
def bar_chart(spec: BarChartSpec) -> BarChart:
"""A whole bar chart as geometry, by the fixed rules in the README."""
width, height, categories, series = spec.width, spec.height, spec.categories, spec.series
if spec.mode not in ("grouped", "stacked"):
raise ValueError("mode must be grouped or stacked, received %s" % (spec.mode,))
if len(categories) == 0:
raise ValueError("a bar chart needs at least one category")
if len(series) == 0:
raise ValueError("a bar chart needs at least one series")
for s in series:
if len(s.values) != len(categories):
raise ValueError(
'series "%s" has %d values but there are %d categories' % (s.name, len(s.values), len(categories))
)
names = [s.name for s in series]
legend = []
top = TOP_WITHOUT_LEGEND
if len(series) > 1:
rows = legend_rows(names, width - 2 * EDGE, CHAR_WIDTH, SWATCH, LEGEND_GAP, LEGEND_ROW)
legend = [
LegendItem(
label=it.label,
row=it.row,
x=round_float(it.x + EDGE, 2),
y=round_float(it.y + EDGE, 2),
width=it.width,
text_x=round_float(it.text_x + EDGE, 2),
)
for it in rows
]
top = EDGE + (rows[-1].row + 1) * LEGEND_ROW + EDGE
stacked = stack([list(s.values) for s in series], "diverging") if spec.mode == "stacked" else None
lo = 0.0
hi = 0.0
for i, s in enumerate(series):
for j, v in enumerate(s.values):
ends = [v] if stacked is None else [stacked[i][j].y0, stacked[i][j].y1]
for e in ends:
if e < lo:
lo = e
if e > hi:
hi = e
if lo == hi:
hi = 1.0
y_count = max(2, int((height - top - BOTTOM) // 50))
y_domain = nice_domain([lo, hi], y_count).domain
y_step = tick_step(y_domain[0], y_domain[1], y_count)
widest = 0
for v in nice_ticks(y_domain[0], y_domain[1], y_count):
widest = max(widest, len(format_tick(v, y_step)))
left = TICK_SIZE + LABEL_PADDING + widest * CHAR_WIDTH + EDGE
plot = plot_area(width, height, Margins(top=top, right=RIGHT, bottom=BOTTOM, left=left))
bottom_y = plot.y + plot.height
y_range = [bottom_y, plot.y]
def y(v: float) -> float:
return linear_scale(y_domain, y_range, v, False)
y_axis = number_axis(y_domain, y_range, y_count, "left", plot.x, TICK_SIZE)
x_range = [plot.x, plot.x + plot.width]
x_axis = band_axis(
categories, x_range, CATEGORY_PADDING_INNER, CATEGORY_PADDING_OUTER, "bottom", bottom_y, TICK_SIZE
)
colors = palette("okabe-ito", len(series), True)
specs = []
meta = []
for i, s in enumerate(series):
for j, c in enumerate(categories):
outer = band_scale(categories, x_range, c, CATEGORY_PADDING_INNER, CATEGORY_PADDING_OUTER, 0.5)
if stacked is not None:
specs.append(
BarSpec(band=outer.start, thickness=outer.width, base=y(stacked[i][j].y0), value=y(stacked[i][j].y1))
)
elif len(series) == 1:
specs.append(BarSpec(band=outer.start, thickness=outer.width, base=y(0), value=y(s.values[j])))
else:
inner = band_scale(names, [outer.start, outer.start + outer.width], s.name, SERIES_PADDING, 0, 0.5)
specs.append(BarSpec(band=inner.start, thickness=inner.width, base=y(0), value=y(s.values[j])))
meta.append((s.name, c, s.values[j], colors[i]))
rects = bar_rects(specs, "vertical")
bars = [
ChartBar(series=m[0], category=m[1], value=m[2], color=m[3], rect=rects[k]) for k, m in enumerate(meta)
]
return BarChart(
width=round_float(width, 2),
height=round_float(height, 2),
plot=plot,
x_axis=x_axis,
y_axis=y_axis,
grid_lines=grid_lines(y_axis, plot.width),
bars=bars,
colors=list(colors),
legend=legend,
)