DX Rating Target Calculator

dxrating-target-calculator.py

#!/usr/bin/env python3

# DX Rating Target Calculator
# Compatible to version 1.60 (CiRCLE)

import matplotlib.pyplot as plt
import numpy as np
import numpy.typing as npt

OUTPUT_PATH = "figure.png"
LEVEL_MIN = 10
LEVEL_MAX = 15
TARGET_RATINGS: list[tuple[int, str]] = [
    (10000, "#5e00bb"),
    (12000, "#7a1100"),
    (13000, "#004a85"),
    (14000, "#ba3800"),
    (14500, "#6e4806"),
    (15000, "#200070"),
    (16000, "#000000"),
]


def adjusted_achievement(
    achievement: npt.NDArray[np.float64],
) -> npt.NDArray[np.float64]:
    # Reference: https://silentblue.remywiki.com/maimai_DX:Rating#Gen_3
    return (
        np.select(
            [
                (0 <= achievement) & (achievement < 50),  # D
                (50 <= achievement) & (achievement < 60),  # C
                (60 <= achievement) & (achievement < 70),  # B
                (70 <= achievement) & (achievement < 75),  # BB
                (75 <= achievement) & (achievement < 80),  # BBB
                (80 <= achievement) & (achievement < 90),  # A
                (90 <= achievement) & (achievement < 94),  # AA
                (94 <= achievement) & (achievement < 97),  # AAA
                (97 <= achievement) & (achievement < 98),  # S
                (98 <= achievement) & (achievement < 99),  # S+
                (99 <= achievement) & (achievement < 99.5),  # SS
                (99.5 <= achievement) & (achievement < 100),  # SS+
                (100 <= achievement) & (achievement < 100.5),  # SSS
                (100.5 <= achievement) & (achievement <= 101),  # SSS+
            ],
            [
                0.050,  # D
                0.080,  # C
                0.096,  # B
                0.112,  # BB
                0.120,  # BBB
                0.136,  # A
                0.152,  # AA
                0.168,  # AAA
                0.200,  # S
                0.203,  # S+
                0.208,  # SS
                0.211,  # SS+
                0.216,  # SSS
                0.224,  # SSS+
            ],
            np.nan,
        )
        * achievement
    )


def main():
    ACHIEVEMENT_MIN = 93
    ACHIEVEMENT_MAX = 101
    NUM_SONGS = 50
    achievements = np.linspace(ACHIEVEMENT_MIN, ACHIEVEMENT_MAX, 4096)
    adjusted = adjusted_achievement(achievements)
    denominator = 1 / (adjusted * NUM_SONGS)

    plt.rcParams["font.family"] = "Helvetica Neue"
    _ = plt.title("DX Rating Target Calculator")
    _ = plt.xlabel("Chart level")
    _ = plt.ylabel("Achievement rate (%)")
    _ = plt.xticks(np.arange(LEVEL_MIN, LEVEL_MAX + 1))
    _ = plt.xticks(np.arange(LEVEL_MIN, LEVEL_MAX + 0.2, 0.2), minor=True)
    _ = plt.yticks([0, 50, 60, 70, 75, 80, 90, 94, 97, 98, 99, 99.5, 100, 100.5, 101])
    _ = plt.yticks(np.arange(0, 101, 1), minor=True)
    _ = plt.xlim(LEVEL_MIN, LEVEL_MAX)
    _ = plt.ylim(94, ACHIEVEMENT_MAX)
    _ = plt.grid(which="both", linewidth=0.5)
    for rating, color in TARGET_RATINGS:
        target_level = rating * denominator
        # 0.5 offsets Math.floor
        target_level[:-1] += 0.5 / adjusted[:-1]
        # 101% must be All Perfect+, offsetting the 1 bonus rating for AP and AP+
        target_level[-1] -= 0.5 / adjusted[-1]
        _ = plt.plot(target_level, achievements, color=color, label=str(rating))
    _ = plt.legend(reverse=True)
    plt.savefig(OUTPUT_PATH, dpi=160, bbox_inches="tight")
    print(f"Saved to {OUTPUT_PATH}")


if __name__ == "__main__":
    main()

figure.png