https://dailypypy.org/tags/dynamic-window/ Recent content in Dynamic-Window on 每日拍拍 Hugo -- gohugo.io zh-tw © 2026 每日拍拍 Fri, 02 Oct 2026 10:59:00 +0800 155076163427069952 154825760438254592 https://dailypypy.org/learn/polars-rolling-dynamic-windows/ Fri, 02 Oct 2026 10:59:00 +0800 https://dailypypy.org/learn/polars-rolling-dynamic-windows/ <!--- 1440x768 prompt: masterpiece, best quality, highres, clean anime illustration, japanese anime style, soft shading, flat color design, 1girl, black hair, green eyes, white off-shoulder shirt, black short skirt, cowboy shot, arms extended while framing two overlapping translucent circular windows with her hands, delighted focused expression, looking at viewer, pastel apricot and soft cornflower blue background, subtle flowing dots passing through the rings without symbols, logos, markings, numbers, letters, or text, neat composition, detailed eyes, cute and smart vibe, minimal background, polished illustration, no text negative prompt: worst quality, bad eye, bad hand, extra limbs, manga, multiple views, monochrome, text, signature dedup note: Planned 2026-10-02 topic `polars-rolling-dynamic-windows` passed a strict 178-post inventory and current-source scan. ../python-polars/ teaches general expressions, GroupBy, and a short Lazy Evaluation introduction; ../polars-lazyframe-query-optimization/ focuses scan sources, pushdown, streaming, explain, and sinks; ../duckdb-window-functions/ teaches analytical SQL frames. This follow-up instead centers time-index sorting contracts, row-anchored rolling groups versus schedule-anchored dynamic groups, every/period/offset, boundary and label semantics, per-device grouping, timezone/DST handling, empty-window policy, and result QA. source check: Reviewed against the current official Polars DataFrame.rolling, DataFrame.group_by_dynamic, time-series grouping, timezone, and testing documentation on 2026-10-02. Examples use `group_by=` rather than the old `by=` name and do not use deprecated `group_by_rolling` or `check_sorted` arguments. ---> <h2 class="relative group">一. 前言：先決定答案掛在哪個時間點 <div id="一-前言先決定答案掛在哪個時間點" class="anchor"></div> <span class="absolute top-0 w-6 transition-opacity opacity-0 ltr:-left-6 rtl:-right-6 not-prose group-hover:opacity-100"> <a class="group-hover:text-primary-300 dark:group-hover:text-neutral-700" style="text-decoration-line: none !important;" href="#%e4%b8%80-%e5%89%8d%e8%a8%80%e5%85%88%e6%b1%ba%e5%ae%9a%e7%ad%94%e6%a1%88%e6%8e%9b%e5%9c%a8%e5%93%aa%e5%80%8b%e6%99%82%e9%96%93%e9%bb%9e" aria-label="定位點">#</a> </span> </h2> <p>時間序列最危險的 bug， 通常不是程式直接噴錯， 而是它很安靜地算出一張看起來合理的表。</p>