pgfplots

# pgfplots — Data Visualization & Plotting **CTAN:** https://ctan.org/pkg/pgfplots **Manual:** `texdoc pgfplots` ## Setup ```latex \usepackage{pgfplots} \pgfplotsset{compat=1.18} % ALWAYS set this — enables latest features % Optional libraries \usepgfplotslibrary{fillbetween, groupplots, statistics, colorbrewer, polar} ``` ## Basic Plot ```latex \begin{tikzpicture} \begin{axis}[ xlabel={$x$}, ylabel={$f(x)$}, title={My Plot}, grid=major, ] \addplot[blue, thick, domain=-3:3, samples=100] {x^2}; \addlegend{$x^2$} \end{axis} \end{tikzpicture} ``` ## Axis Environments | Environment | Description | |-------------|-------------| | `axis` | Standard linear axes | | `semilogxaxis` | Log scale on x-axis | | `semilogyaxis` | Log scale on y-axis | | `loglogaxis` | Log scale on both axes | | `polaraxis` | Polar coordinates (requires `polar` library) | ## Axis Options Reference | Option | Example | Description | |--------|---------|-------------| | `xlabel` | `xlabel={Time (s)}` | X-axis label | | `ylabel` | `ylabel={Voltage}` | Y-axis label | | `title` | `title={Results}` | Plot title | | `xmin/xmax` | `xmin=0, xmax=10` | Axis limits | | `ymin/ymax` | `ymin=-1, ymax=1` | Axis limits | | `domain` | `domain=0:2*pi` | Default plot domain | | `samples` | `samples=200` | Default sample count | | `grid` | `grid=major` | `major`, `minor`, `both`, `none` | | `legend pos` | `legend pos=north west` | Legend placement | | `width/height` | `width=10cm` | Axis dimensions | | `axis lines` | `axis lines=middle` | `box`, `left`, `middle`, `none` | | `enlargelimits` | `enlargelimits=0.1` | Pad axis range | | `xtick` | `xtick={0,1,...,5}` | Custom tick positions | | `xticklabels` | `xticklabels={A,B,C}` | Custom tick labels | | `x tick label style` | `x tick label style={rotate=45}` | Tick label formatting | | `legend style` | `legend style={at={(0.5,-0.2)}}` | Legend customization | | `cycle list name` | `cycle list name=color list` | Color cycling | | `scaled ticks` | `scaled ticks=false` | Disable tick scaling | | `restrict y to domain` | `restrict y to domain=-10:10` | Clip extreme values | ## Plot Types & Examples ### Line Plot (from expression) ```latex \begin{axis}[domain=0:2*pi, samples=100, grid=major, legend pos=south west] \addplot[blue, thick] {sin(deg(x))}; \addplot[red, thick, dashed] {cos(deg(x))}; \legend{$\sin(x)$, $\cos(x)$} \end{axis} ``` ### Line Plot (from data) ```latex \begin{axis}[xlabel=Year, ylabel=Value] \addplot coordinates { (2018, 10) (2019, 15) (2020, 12) (2021, 20) (2022, 25) }; \end{axis} ``` ### Scatter Plot ```latex \begin{axis}[only marks, xlabel=$x$, ylabel=$y$] \addplot[mark=*, blue] coordinates { (1,2) (2,3.5) (3,2.8) (4,5.1) (5,4.2) }; % Or with mark options: \addplot+[mark=o, mark size=3pt, red] coordinates { ... }; \end{axis} ``` ### Bar Chart ```latex \begin{axis}[ ybar, % vertical bars (xbar for horizontal) symbolic x coords={A, B, C, D}, xtick=data, ylabel={Count}, nodes near coords, % value labels on bars bar width=15pt, ] \addplot coordinates {(A,20) (B,35) (C,30) (D,15)}; \addplot coordinates {(A,25) (B,20) (C,40) (D,10)}; \legend{2022, 2023} \end{axis} ``` ### Stacked Bar ```latex \begin{axis}[ybar stacked, symbolic x coords={Q1,Q2,Q3,Q4}, xtick=data] \addplot coordinates {(Q1,10) (Q2,15) (Q3,12) (Q4,18)}; \addplot coordinates {(Q1,8) (Q2,10) (Q3,15) (Q4,12)}; \legend{Product A, Product B} \end{axis} ``` ### Histogram ```latex \usepgfplotslibrary{statistics} \begin{axis}[ybar interval, ylabel=Frequency, xlabel=Value] \addplot+[hist={bins=10, data min=0, data max=100}] table[y index=0] {data.csv}; \end{axis} ``` ### Box Plot ```latex \usepgfplotslibrary{statistics} \begin{axis}[boxplot/draw direction=y] \addplot[boxplot prepared={ lower whisker=2, lower quartile=4, median=6, upper quartile=8, upper whisker=10 }] coordinates {}; \end{axis} ``` ### Area / Fill Between ```latex \usepgfplotslibrary{fillbetween} \begin{axis} \addplot[name path=upper, blue, thick, domain=0:4] {x^2}; \addplot[name path=lower, red, thick, domain=0:4] {x}; \addplot[fill=blue!10] fill between[of=upper and lower, soft clip={domain=1:3}]; \end{axis} ``` ### Error Bars ```latex \begin{axis} \addplot+[error bars/.cd, y dir=both, y explicit] coordinates { (1, 2) +- (0, 0.5) (2, 4) +- (0, 0.8) (3, 3) +- (0, 0.3) }; \end{axis} ``` ### 3D Surface ```latex \begin{axis}[view={45}{30}, xlabel=$x$, ylabel=$y$, zlabel=$z$, colormap/viridis] \addplot3[surf, domain=-2:2, domain y=-2:2, samples=25] {exp(-x^2 - y^2)}; \end{axis} ``` ### 3D Mesh ```latex \begin{axis}[view={60}{30}] \addplot3[mesh, domain=-2:2, domain y=-2:2, samples=20] {sin(deg(x)) * cos(deg(y))}; \end{axis} ``` ### Contour ```latex \begin{axis}[view={0}{90}] % top-down view \addplot3[contour filled, domain=-2:2, domain y=-2:2, samples=30] {exp(-x^2 - y^2)}; \end{axis} ``` ### Parametric Plot ```latex \begin{axis}[axis equal] \addplot[domain=0:360, samples=100, thick, blue] ({cos(x)}, {sin(x)}); % circle \end{axis} ``` ### Polar Plot ```latex \usepgfplotslibrary{polar} \begin{polaraxis} \addplot[domain=0:360, samples=100, thick] {1 + cos(x)}; % cardioid \end{polaraxis} ``` ## Data from Files ```latex % CSV file: data.csv % x, y % 1, 2.3 % 2, 4.1 % ... \begin{axis} \addplot table[col sep=comma, x=x, y=y] {data.csv}; % TSV (default separator is space/tab) \addplot table[x index=0, y index=1] {data.tsv}; % With expression on column \addplot table[x=time, y expr=\thisrow{value}*100] {data.csv}; \end{axis} ``` ## Color Maps ```latex % Built-in colormaps colormap/hot, colormap/cool, colormap/viridis, colormap/bluered, colormap/greenyellow, colormap/jet % Custom \pgfplotsset{ colormap={mymap}{rgb255(0cm)=(0,0,180); rgb255(1cm)=(0,180,0); rgb255(2cm)=(180,0,0)} } % Colorbar \begin{axis}[colorbar, colormap/viridis] ``` ## Multiple Axes ```latex \begin{tikzpicture} \begin{axis}[ axis y line*=left, xlabel=Time, ylabel=Temperature, ymin=0, ymax=100, ] \addplot[blue, thick] coordinates {(1,20)(2,40)(3,60)(4,80)}; \label{plot:temp} \end{axis} \begin{axis}[ axis y line*=right, axis x line=none, ylabel=Pressure, ymin=0, ymax=10, ] \addplot[red, thick, dashed] coordinates {(1,2)(2,5)(3,3)(4,8)}; \label{plot:press} \end{axis} \end{tikzpicture} ``` ## Group Plots ```latex \usepgfplotslibrary{groupplots} \begin{tikzpicture} \begin{groupplot}[ group style={group size=2 by 2, horizontal sep=1.5cm, vertical sep=1.5cm}, width=6cm, height=5cm, ] \nextgroupplot[title=Plot 1] \addplot {x}; \nextgroupplot[title=Plot 2] \addplot {x^2}; \nextgroupplot[title=Plot 3] \addplot {sqrt(x)}; \nextgroupplot[title=Plot 4] \addplot {ln(x)}; \end{groupplot} \end{tikzpicture} ``` ## Annotations ```latex \begin{axis} \addplot[blue, thick, domain=0:5] {x^2}; % Pin annotation \node[pin=60:{Maximum}] at (axis cs:4, 16) {}; % Arrow annotation \draw[->, thick] (axis cs:2, 10) -- (axis cs:3, 9) node[above, pos=0] {Note}; % Vertical line \draw[dashed, gray] (axis cs:2.5, 0) -- (axis cs:2.5, 25); % Horizontal band \draw[fill=red!10, draw=none] (axis cs:0,5) rectangle (axis cs:5,10); % Text node \node at (axis cs:1, 20) {$f(x) = x^2$}; \end{axis} ``` ## Mark Options | Mark | Description | |------|-------------| | `*` | Filled circle | | `o` | Open circle | | `square*` | Filled square | | `square` | Open square | | `triangle*` | Filled triangle |