[Tex/LaTex] How to make a simple graph with grids using pgfplots

pgfmathpgfplots

I want it to look like this:

example

Preferably with comments so I can learn how to make my own!

Best Answer

This should get you started:

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.11}

\begin{document}

\begin{tikzpicture}
\begin{axis}[
  axis lines=middle,
  grid=major,
  xmin=-5,
  xmax=5,
  ymin=-3,
  ymax=5,
  xlabel=$x$,
  ylabel=$y$,
  xtick={-4,-3,...,4},
  ytick={-2,-1,...,4},
  tick style={very thick},
  legend style={
  at={(rel axis cs:0,1)},
  anchor=north west,draw=none,inner sep=0pt,fill=gray!10}
]
\addplot[blue,thick,samples=100] {x^2};
\addlegendentry{$y=x^2$}
\end{axis}
\end{tikzpicture}

\end{document}

enter image description here

The code itself is self explanatory IMO. For details, run texdoc pgfplots from command prompt/terminal and look in to the pgfplots manual.

Code:

\documentclass{article}
\usepackage{amsmath}
\usepackage{pgfplots}

\begin{document}

\begin{tikzpicture}[domain=0:3]
\begin{axis}[xlabel={$T_{\text{meas}}$}, ylabel={$T_{\text{cal}}$}]
\addplot[scatter, only marks, scatter src=\thisrow{class},
      error bars/.cd, y dir=both, x dir=both, y explicit, x explicit, error bar style={color=mapped color}]
      table[x=x,y=y,x error=xerr,y error=yerr] {
    x       xerr    y        yerr       class
    0.98521 0.00031 1        0.000001   0
    0.49238 0.00044 0.5      0.00000025 0
    1.09346 0.00032 1.111111 0.0000012  0
    1.23021 0.00078 1.25     0.0000016  0
    1.40567 0.00047 1.428571 0.000002   0
    1.63971 0.00064 1.666667 0.0000028  0
    1.96753 0.00063 2        0.000004   0
};
\end{axis}
\end{tikzpicture}
\end{document}

[Tex/LaTex] How to make label (node) to appear in front of markers in pgfplots

Normally markers are drawn on top of all plots in an axis environment (clip mode=global, default) or at least on top of the single plot (clip mode=individual) to avoid clipping the markers. In your code the node is part of the plot path and therefore behind the markers.

Version 1

You can shift the markers in the layer axis tick labels which is behind of the main layer:

\documentclass[border=5mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\begin{document}
\begin{tikzpicture}
\pgfplotsset{
  set layers,% using layers
  mark layer=axis tick labels% defines the layer of the marks
}
\begin{axis}
\addplot coordinates {
   (0.5,0.5) (1, 1) (1.5,1.5)
  } node[pos=0.5]{\color{green}{LABEL}};
\end{axis}
\end{tikzpicture}
\end{document}

enter image description here

Note that then all markers will be behind all plots in the same axis environment.

Version 2

Set a coordinate in the plot path and draw the node in a pgfonlayer environment on the axis foreground layer:

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\begin{document}
\begin{tikzpicture}
\pgfplotsset{set layers}% using layers
\begin{axis}[set layers]
\addplot coordinates {
     (0.5,0.5) (1, 1) (1.5,1.5)
  } coordinate[pos=0.5](p1);% coordinate in the middle of the plot path
\begin{pgfonlayer}{axis foreground}
  \node at (p1){\color{green}{LABEL}};% draw the node in the axis foreground
\end{pgfonlayer}
\end{axis}
\end{tikzpicture}
\end{document}

Unfortunately I don't know how to change the layer for the node directly in their options. But maybe there is such a possibility.

Version 3

Use clip mode=invidual, set a coordinate in the plot path and draw the node when the plot is finished:

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\begin{document}
\begin{tikzpicture}
\begin{axis}[clip mode=individual]
\addplot coordinates {
   (0.5,0.5) (1, 1) (1.5,1.5)
} coordinate[pos=0.5](p1);% coordinate in the middle of the plot path
\node at (p1){\color{green}{LABEL}};
\end{axis}
\end{tikzpicture}
\end{document}

Edit

From the manual v. 1.10, page 349:

The layers/standard layer configuration is defined by

\pgfplotsset{
  layers/standard/.define layer set=
    {axis background,axis grid,axis ticks,axis lines,axis tick labels,main,%
      axis descriptions,axis foreground}
    {
      grid style= {/pgfplots/on layer=axis grid},
      tick style= {/pgfplots/on layer=axis ticks},
      axis line style= {/pgfplots/on layer=axis lines},
      label style= {/pgfplots/on layer=axis descriptions},
      legend style= {/pgfplots/on layer=axis descriptions},
      title style= {/pgfplots/on layer=axis descriptions},
      colorbar style= {/pgfplots/on layer=axis descriptions},
      ticklabel style= {/pgfplots/on layer=axis tick labels},
      axis background@ style={/pgfplots/on layer=axis background},
      3d box foreground style={/pgfplots/on layer=axis foreground},
    },
}

You can define a new layer set and for example add a new layer behind main:

\documentclass[border=5mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}

\pgfplotsset{
  layers/mylayers/.define layer set=
    {axis background,axis grid,axis ticks,axis lines,axis tick labels,%
      axis mymarks,% additional layer behind main
      main,axis descriptions,axis foreground}
    {/pgfplots/layers/standard}% re-uses the style definitions of layers/standard
}
\begin{document}
\begin{tikzpicture}
\pgfplotsset{
  set layers=mylayers,% using mylayers
  mark layer=axis mymarks% defines the layer of the marks
}
\begin{axis}
\addplot coordinates {
   (0.5,0.5) (1, 1) (1.5,1.5)
  } node[pos=0.5]{\color{green}{LABEL}};
\end{axis}
\end{tikzpicture}
\end{document}