📦 箱线图生成器（五数概括 + 离群值）Box Plot Maker (Five-Number Summary)
输入一组或多组数据，算出五数概括（最小值、Q1、中位数、Q3、最大值）、四分位距 IQR、1.5×IQR 围栏和离群值，并画出可下载的 SVG 箱线图；多组数据并排对比，四分位数可选 4 种常见算法。Enter one or more data sets to get the five-number summary (minimum, Q1, median, Q3, maximum), the IQR, the 1.5 × IQR fences and any outliers, drawn as a downloadable SVG box plot. Several groups are compared side by side, and the quartiles can use any of four common methods.
使用说明与常见问题How-to & FAQ
「箱线图生成器（五数概括 + 离群值）」是什么？What is the Box Plot Maker (Five-Number Summary) tool?
输入一组或多组数据，算出五数概括（最小值、Q1、中位数、Q3、最大值）、四分位距 IQR、1.5×IQR 围栏和离群值，并画出可下载的 SVG 箱线图；多组数据并排对比，四分位数可选 4 种常见算法。Enter one or more data sets to get the five-number summary (minimum, Q1, median, Q3, maximum), the IQR, the 1.5 × IQR fences and any outliers, drawn as a downloadable SVG box plot. Several groups are compared side by side, and the quartiles can use any of four common methods.
如何使用「箱线图生成器（五数概括 + 离群值）」？How do I use the Box Plot Maker (Five-Number Summary) tool?
在「箱线图生成器（五数概括 + 离群值）」中，填写「四分位数算法」等参数，结果会随输入实时计算并显示在下方。In the Box Plot Maker (Five-Number Summary): Fill in "Quartile method"; results are recalculated instantly as you type.
四种四分位数算法有什么区别？How do the four quartile methods differ?
“排除中位数”：先找中位数，再分别取下半部分和上半部分（数据个数为奇数时不含中位数）的中位数，这是多数教科书和 TI 计算器的做法；“包含中位数”（Tukey 折叶点）在个数为奇数时把中位数同时算进两半；“线性插值”按位置 (n−1)p 插值，等同 Excel 的 QUARTILE.INC 和 R 的默认算法；“QUARTILE.EXC”按位置 (n+1)p 插值。数据少时几种结果可能不同，数据多时非常接近。'Exclude the median' takes the median, then the medians of the lower and upper halves, leaving the median out when n is odd — the textbook and TI-calculator method. 'Include the median' (Tukey hinges) puts it in both halves when n is odd. 'Linear interpolation' interpolates at position (n−1)p, the same as Excel's QUARTILE.INC and R's default. 'QUARTILE.EXC' interpolates at (n+1)p. With small data sets they can disagree; with large ones they are very close.
离群值怎么判断？How are outliers identified?
用 Tukey 的 1.5×IQR 规则：IQR = Q3 − Q1，低于 Q1 − 1.5×IQR 或高于 Q3 + 1.5×IQR 的点算离群值，图中画成红色空心圆；须线只延伸到围栏以内最远的数据点。With Tukey's 1.5 × IQR rule: IQR = Q3 − Q1, and points below Q1 − 1.5 × IQR or above Q3 + 1.5 × IQR are outliers, drawn as red open circles. The whiskers stop at the furthest data points inside the fences.
怎么画多组对比？How do I compare several groups?
每行写一组数据，最多 12 组，可在前面加“名称:”（如 “男: 172 168 181”）。所有箱线图共用同一条坐标轴，方便直接比较。默认数据只是示例。Put one group per line, up to 12, optionally starting with 'name:' (e.g. 'Men: 172 168 181'). All boxes share one axis so they can be compared directly. The default data is only an example.
图能保存吗？Can I save the chart?
可以，点“下载 SVG”保存矢量图，可直接插入 Word、PPT、网页，或用浏览器、Inkscape 转成 PNG。Yes — 'Download SVG' saves a vector image you can drop into Word, PowerPoint or a web page, or convert to PNG with a browser or Inkscape.
计算精度如何？How precise are the results?
「箱线图生成器（五数概括 + 离群值）」使用 JavaScript 双精度浮点数（约 15–16 位有效数字）；极大或极小的数值可能存在精度误差。The Box Plot Maker (Five-Number Summary) uses double-precision floating point (about 15–16 significant digits); very large or very small values may lose precision.
「箱线图生成器（五数概括 + 离群值）」免费吗？需要注册吗？Is the Box Plot Maker (Five-Number Summary) free? Do I need an account?
「箱线图生成器（五数概括 + 离群值）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Box Plot Maker (Five-Number Summary) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.