plotnine.py

""" anyplot.ai
rose-basic: Basic Rose Chart
Library: plotnine 0.15.3 | Python 3.13.13
Quality: 85/100 | Updated: 2026-04-30
"""

import math
import os
import sys


# Remove this file's own directory from sys.path so that "plotnine" resolves
# to the installed library rather than this file (Python 3.13 naming-collision fix).
_script_dir = os.path.dirname(os.path.abspath(__file__))
sys.path = [p for p in sys.path if os.path.realpath(p) != os.path.realpath(_script_dir)]

import numpy as np
import pandas as pd
from matplotlib import colormaps
from matplotlib.colors import Normalize, to_hex
from plotnine import (
    aes,
    element_blank,
    element_rect,
    element_text,
    geom_line,
    geom_polygon,
    geom_text,
    ggplot,
    labs,
    scale_fill_manual,
    scale_x_continuous,
    scale_y_continuous,
    theme,
)


# Theme tokens
THEME = os.getenv("ANYPLOT_THEME", "light")
PAGE_BG = "#FAF8F1" if THEME == "light" else "#1A1A17"
INK = "#1A1A17" if THEME == "light" else "#F0EFE8"
INK_SOFT = "#4A4A44" if THEME == "light" else "#B8B7B0"
INK_MUTED = "#6B6A63" if THEME == "light" else "#A8A79F"

# Data - Monthly rainfall (mm) for a temperate climate
months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
rainfall = [78, 62, 55, 48, 52, 68, 82, 85, 72, 88, 95, 82]

n = len(months)

# Viridis colors per month based on rainfall value (continuous colormap for value-encoded data)
_norm = Normalize(vmin=min(rainfall), vmax=max(rainfall))
_cmap = colormaps["viridis"]
month_colors = {month: to_hex(_cmap(_norm(val))) for month, val in zip(months, rainfall, strict=True)}

# Create wedge polygons for each month
n_arc_points = 30
wedge_rows = []
for i, (month, value) in enumerate(zip(months, rainfall, strict=True)):
    start_angle = math.pi / 2 - (i * 2 * math.pi / n)
    end_angle = math.pi / 2 - ((i + 1) * 2 * math.pi / n)
    gap = 0.02
    start_angle += gap
    end_angle -= gap
    wedge_rows.append({"x": 0, "y": 0, "month": month, "order": 0})
    for j, angle in enumerate(np.linspace(start_angle, end_angle, n_arc_points)):
        wedge_rows.append({"x": value * math.cos(angle), "y": value * math.sin(angle), "month": month, "order": j + 1})
    wedge_rows.append({"x": 0, "y": 0, "month": month, "order": n_arc_points + 1})

df = pd.DataFrame(wedge_rows)
df["month"] = pd.Categorical(df["month"], categories=months, ordered=True)

# Radial gridlines (circles)
grid_rows = []
grid_angles = np.linspace(0, 2 * math.pi, 101)
for radius in [20, 40, 60, 80, 100]:
    for angle in grid_angles:
        grid_rows.append({"x": radius * math.cos(angle), "y": radius * math.sin(angle), "radius": radius})
grid_df = pd.DataFrame(grid_rows)

# Spoke lines from center to edge
spoke_rows = []
for i in range(n):
    angle = math.pi / 2 - (i * 2 * math.pi / n)
    spoke_rows.append({"x": 0, "y": 0, "spoke_id": i})
    spoke_rows.append({"x": 105 * math.cos(angle), "y": 105 * math.sin(angle), "spoke_id": i})
spoke_df = pd.DataFrame(spoke_rows)

# Month labels positioned outside the chart
label_rows = []
for i, month in enumerate(months):
    center_angle = math.pi / 2 - ((i + 0.5) * 2 * math.pi / n)
    label_rows.append({"label": month, "x": 120 * math.cos(center_angle), "y": 120 * math.sin(center_angle)})
label_df = pd.DataFrame(label_rows)

# Value labels positioned along the top-right spoke
value_label_rows = [{"label": str(r), "x": 6, "y": r + 4} for r in [20, 40, 60, 80, 100]]
value_label_df = pd.DataFrame(value_label_rows)

# Plot
plot = (
    ggplot()
    + geom_line(
        aes(x="x", y="y", group="radius"), data=grid_df, color=INK_SOFT, size=0.4, alpha=0.15, linetype="dashed"
    )
    + geom_line(aes(x="x", y="y", group="spoke_id"), data=spoke_df, color=INK_SOFT, size=0.3, alpha=0.12)
    + geom_polygon(aes(x="x", y="y", fill="month", group="month"), data=df, color=PAGE_BG, size=0.3, alpha=0.88)
    + geom_text(aes(x="x", y="y", label="label"), data=label_df, size=14, fontweight="bold", color=INK)
    + geom_text(aes(x="x", y="y", label="label"), data=value_label_df, size=10, color=INK_MUTED)
    + scale_fill_manual(values=month_colors)
    + scale_x_continuous(limits=(-142, 142))
    + scale_y_continuous(limits=(-142, 142))
    + labs(title="Monthly Rainfall (mm) · rose-basic · plotnine · anyplot.ai")
    + theme(
        figure_size=(12, 12),
        plot_background=element_rect(fill=PAGE_BG, color=PAGE_BG),
        panel_background=element_rect(fill=PAGE_BG),
        plot_title=element_text(size=22, ha="center", color=INK),
        axis_title=element_blank(),
        axis_text=element_blank(),
        axis_ticks=element_blank(),
        axis_line=element_blank(),
        panel_grid_major=element_blank(),
        panel_grid_minor=element_blank(),
        panel_border=element_blank(),
        legend_position="none",
    )
)

# Save
plot.save(f"plot-{THEME}.png", dpi=300)