Function _get_periods_per_ymd

pandas/plotting/_matplotlib/converter.py:537–570

(freq: BaseOffset)

def _get_periods_per_ymd(freq: BaseOffset) -> tuple[int, int, int]:
    # error: "BaseOffset" has no attribute "_period_dtype_code"
    dtype_code = freq._period_dtype_code  # type: ignore[attr-defined]
    freq_group = FreqGroup.from_period_dtype_code(dtype_code)

    ppd = -1  # placeholder for above-day freqs

    if dtype_code >= FreqGroup.FR_HR.value:  # pyright: ignore[reportAttributeAccessIssue]
        # error: "BaseOffset" has no attribute "_creso"
        ppd = periods_per_day(freq._creso)  # type: ignore[attr-defined]
        ppm = 28 * ppd
        ppy = 365 * ppd
    elif freq_group == FreqGroup.FR_BUS:
        ppm = 19
        ppy = 261
    elif freq_group == FreqGroup.FR_DAY:
        ppm = 28
        ppy = 365
    elif freq_group == FreqGroup.FR_WK:
        ppm = 3
        ppy = 52
    elif freq_group == FreqGroup.FR_MTH:
        ppm = 1
        ppy = 12
    elif freq_group == FreqGroup.FR_QTR:
        ppm = -1  # placerholder
        ppy = 4
    elif freq_group == FreqGroup.FR_ANN:
        ppm = -1  # placeholder
        ppy = 1
    else:
        raise NotImplementedError(f"Unsupported frequency: {dtype_code}")

    return ppd, ppm, ppy


@functools.cache