![pgfplots 简单 x 过滤器错误](https://linux22.com/image/464972/pgfplots%20%E7%AE%80%E5%8D%95%20x%20%E8%BF%87%E6%BB%A4%E5%99%A8%E9%94%99%E8%AF%AF.png)
为了绘制 t 作为 n 函数的图形,我试图过滤文件中 k 不同于 5 的行。这是投影仪:
% !TEX TS-program = pdflatexmk
\documentclass[aspectratio = 169]{beamer}
\setbeamertemplate{navigation symbols}{}
\usetheme{Boadilla}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}
\usepackage{graphicx}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{hyperref}
\usepackage{pgfplots}
\pgfplotsset{compat = newest, width = \textwidth, height = \axisdefaultheight}
\begin{document}
\begin{frame}
\frametitle{Tree}
\framesubtitle{ Time as a function of $n$}
\begin{center}
\begin{tikzpicture}
\begin{axis}[
unbounded coords=discard,
]
\addplot+ [
x filter/.expression={
\thisrow{k} == 5 ? x : nan
},
] table [
col sep = comma,
x = n,
y = tmed,
] {./data/test-tree.csv};
\end{axis}
\end{tikzpicture}
\end{center}
\end{frame} % This is line 137 in the full document
\end{document}
这会导致以下错误,我已经能够将其隔离到过滤器本身:
./presentation.tex:137: Missing number, treated as zero.
<to be read again>
=
l.137 \end{frame}
^^M
?
我有点困惑,因为我的过滤器几乎完全照搬了pgfplots 文档,但即使复制粘贴他们的例子也不起作用:
% Preamble: \pgfplotsset{width=7cm,compat=1.18}
\begin{tikzpicture}
\begin{axis}
\addplot+[
x filter/.expression={
\thisrow{W} == 42 ? 0.2 : x
},
] table {
x y W
0 0 41
0.5 0.5 42
1 1 43
};
\end{axis}
\end{tikzpicture}
作为参考,这里是该文件的一个示例test-tree.csv
:(省略约 1900 行)
n, k, tq1, tmed, tq3
1, 1, 0, 1, 1
1, 2, 0, 1, 1
1, 3, 0, 1, 1
1, 4, 0, 1, 1
1, 5, 0, 1, 1
1, 6, 0, 1, 1
1, 7, 0, 1, 1
1, 8, 0, 0, 1
1, 9, 0, 1, 1