# How to construct a confusion matrix in LaTeX?

A confusion matrix looks like:

Is there an easy way to do the same using LaTeX?

Otherwise I could just create a diagram with any software.

• @kkudi: The figure I attached is what you want to refer? Jun 8 '11 at 16:28
• Perhaps you can adapt the example for sfgame.sty for you purposes. Also you may want to delete your duplicate post at Stack Overflow since this question is more on topic here.
– N.N.
Jun 8 '11 at 16:52
• it sounds too time-consuming. thanks for your comments. I'm going to create one using OmniGraffle. Cheers. Jun 8 '11 at 17:18
• You may also wanna have a look at this LaTeX community post.
– N.N.
Jun 8 '11 at 17:25
• Since you have some responses below that seem to answer your question, please consider marking one of them as ‘Accepted’ by clicking on the tickmark below their vote count. This shows which answer helped you most, and it assigns reputation points to the author of the answer (and to you!). Jun 10 '11 at 21:34

## 7 Answers

Here's a solution without TikZ:

\documentclass{article}
\usepackage{array}
\usepackage{multirow}

\newcommand\MyBox[2]{
\fbox{\lower0.75cm
\vbox to 1.7cm{\vfil
\hbox to 1.7cm{\hfil\parbox{1.4cm}{#1\\#2}\hfil}
\vfil}%
}%
}

\begin{document}

\noindent
\renewcommand\arraystretch{1.5}
\setlength\tabcolsep{0pt}
\begin{tabular}{c >{\bfseries}r @{\hspace{0.7em}}c @{\hspace{0.4em}}c @{\hspace{0.7em}}l}
\multirow{10}{*}{\parbox{1.1cm}{\bfseries\raggedleft actual\\ value}} &
& \multicolumn{2}{c}{\bfseries Prediction outcome} & \\
& & \bfseries p & \bfseries n & \bfseries total \\
& p$'$ & \MyBox{True}{Positive} & \MyBox{False}{Negative} & P$'$ \\[2.4em]
& n$'$ & \MyBox{False}{Positive} & \MyBox{True}{Negative} & N$'$ \\
& total & P & N &
\end{tabular}

\end{document}


In a comment it has been requested to rotate one of the labels; this can be easily done using \rotatebox from graphicx:

\documentclass{article}
\usepackage{array}
\usepackage{graphicx}
\usepackage{multirow}

\newcommand\MyBox[2]{
\fbox{\lower0.75cm
\vbox to 1.7cm{\vfil
\hbox to 1.7cm{\hfil\parbox{1.4cm}{#1\\#2}\hfil}
\vfil}%
}%
}

\begin{document}

\noindent
\renewcommand\arraystretch{1.5}
\setlength\tabcolsep{0pt}
\begin{tabular}{c >{\bfseries}r @{\hspace{0.7em}}c @{\hspace{0.4em}}c @{\hspace{0.7em}}l}
\multirow{10}{*}{\rotatebox{90}{\parbox{1.1cm}{\bfseries\centering actual\\ value}}} &
& \multicolumn{2}{c}{\bfseries Prediction outcome} & \\
& & \bfseries p & \bfseries n & \bfseries total \\
& p$'$ & \MyBox{True}{Positive} & \MyBox{False}{Negative} & P$'$ \\[2.4em]
& n$'$ & \MyBox{False}{Positive} & \MyBox{True}{Negative} & N$'$ \\
& total & P & N &
\end{tabular}

\end{document}


• very good. It looks like that a lot users think that TikZ is needed for every problem ... By the way, you can use \parbox[c][1.7cm][c]{1.7cm}{...}
– user2478
Jun 9 '11 at 6:51
• @Herbert: Indeed.
– TH.
Jun 9 '11 at 12:29
• @Herbert: thanks. And yes, you're absolutely right. Jun 9 '11 at 13:33
• How can we rotate actual value by 90 degrees? Sep 14 '13 at 19:47
• @Rasoul please see my updated answer. Sep 14 '13 at 20:31

Here is some LaTeX code I used to produce related tables for a tutorial. It might get you close to what you're looking for, although you'll probably want to change the layout.

\begin{tabular}{l|l|c|c|c}
\multicolumn{2}{c}{}&\multicolumn{2}{c}{True diagnosis}&\\
\cline{3-4}
\multicolumn{2}{c|}{}&Positive&Negative&\multicolumn{1}{c}{Total}\\
\cline{2-4}
\multirow{2}{*}{Screening test}& Positive & $a$ & $b$ & $a+b$\\
\cline{2-4}
& Negative & $c$ & $d$ & $c+d$\\
\cline{2-4}
\multicolumn{1}{c}{} & \multicolumn{1}{c}{Total} & \multicolumn{1}{c}{$a+c$} & \multicolumn{    1}{c}{$b+d$} & \multicolumn{1}{c}{$N$}\\
\end{tabular}


% need the pifont package
\begin{tabular}{l|l|>{\columncolor{gray!20}}l|l|l}
%\begin{tabular}{l|l|l|l|l}
\multicolumn{2}{c}{}&\multicolumn{2}{c}{True diagnosis}&\\
\cline{3-4}
\multicolumn{2}{c|}{}&\multicolumn{1}{c|}{Positive}&\multicolumn{1}{c|}{Negative}&\multicolu    mn{1}{c}{}\\
%\cline{2-4}
\hhline{~|---}
\multirow{2}{*}{Screening test}& Positive & TP & FP ($\alpha$) &\ding{214} PPV\\
%\cline{2-4}
\hhline{~|---}
& Negative & FN ($\beta$) & TN & \ding{214} NPV\\
%\cline{2-4}
\hhline{~|---}
\multicolumn{1}{c}{} & \multicolumn{1}{c}{} &
\multicolumn{1}{c}{\multirow{2}{*}{\parbox{2em}{\vskip1ex\ding{215}\\ Se}}} & \multicolumn{1    }{c}{\multirow{2}{*}{\parbox{2em}{\vskip1ex\ding{215}\\ Sp}}} &\multicolumn{1}{c}{}\\
\end{tabular}


• Which packages will I need to construct this table? Jul 27 '16 at 20:43
• it would be nice if the packages required were included with this answer
– baxx
Feb 7 '19 at 13:34
• two things: 1) there are multiple spaces within a '\multirow' command causing compilation errors 2) you need the following packages additionally hhline and multirow and colortbl Mar 30 '20 at 15:22

It's quite easy making such a thing with TikZ, once you get the hang of it.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{positioning}
\begin{document}
\begin{tikzpicture}[
box/.style={draw,rectangle,minimum size=2cm,text width=1.5cm,align=left}]
\matrix (conmat) [row sep=.1cm,column sep=.1cm] {
\node (tpos) [box,
label=left:$$\mathbf{p'}$$,
label=above:$$\mathbf{p}$$,
] {True \\ positive};
&
\node (fneg) [box,
label=above:\textbf{n},
label=above right:\textbf{total},
label=right:$$\mathrm{P}'$$] {False \\ negative};
\\
\node (fpos) [box,
label=left:$$\mathbf{n'}$$,
label=below left:\textbf{total},
label=below:P] {False \\ positive};
&
\node (tneg) [box,
label=right:$$\mathrm{N}'$$,
label=below:N] {True \\ negative};
\\
};
\node [left=.05cm of conmat,text width=1.5cm,align=right] {\textbf{actual \\ value}};
\node [above=.05cm of conmat] {\textbf{prediction outcome}};
\end{tikzpicture}
\end{document}


To rotate actual value you can replace

\node [left=.05cm of conmat,text width=1.5cm,align=right] {\textbf{actual \\ value}};


with

 \node [rotate=90,left=.05cm of conmat,anchor=center,text width=1.5cm,align=center] {\textbf{actual \\ value}};


• Adopting your code to another example, I can't help but notice that the baseline of the "p" above "True positive" is higher than "n"'s. Doesn't hurt much here, but looks weird when you have longer labels such as "low", "medium", and "high". Any ideas on this? (Thanks, btw.)
– sr_
Jun 24 '15 at 11:36
• @sr_ Good point. You can add every label/.style={text depth=\depthof{p}} to the tikzpicture options. Jun 24 '15 at 11:40

To create a color confusion matrix like this:

You can use the following code.

\documentclass[english]{article}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\usepackage{babel}
\usepackage[table]{xcolor}
\usepackage{collcell}
\usepackage{hhline}
\usepackage{pgf}
\usepackage{multirow}

\def\colorModel{hsb} %You can use rgb or hsb

\newcommand\ColCell[1]{
\pgfmathparse{#1<50?1:0}  %Threshold for changing the font color into the cells
\ifnum\pgfmathresult=0\relax\color{white}\fi
\pgfmathsetmacro\compA{0}      %Component R or H
\pgfmathsetmacro\compB{#1/100} %Component G or S
\pgfmathsetmacro\compC{1}      %Component B or B
\edef\x{\noexpand\centering\noexpand\cellcolor[\colorModel]{\compA,\compB,\compC}}\x #1
}
\newcolumntype{E}{>{\collectcell\ColCell}m{0.4cm}<{\endcollectcell}}  %Cell width
\newcommand*\rot{\rotatebox{90}}

\begin{document}
\newcommand\items{3}   %Number of classes
\arrayrulecolor{white} %Table line colors
\noindent\begin{tabular}{cc*{\items}{|E}|}
\multicolumn{1}{c}{} &\multicolumn{1}{c}{} &\multicolumn{\items}{c}{Predicted} \\ \hhline{~*\items{|-}|}
\multicolumn{1}{c}{} &
\multicolumn{1}{c}{} &
\multicolumn{1}{c}{\rot{Class A}} &
\multicolumn{1}{c}{\rot{Class B}} &
\multicolumn{1}{c}{\rot{Class C}} \\ \hhline{~*\items{|-}|}
\multirow{\items}{*}{\rotatebox{90}{Actual}}
&Class A  & 100   & 0  & 10   \\ \hhline{~*\items{|-}|}
&Class B  & 10   & 80  & 10   \\ \hhline{~*\items{|-}|}
&Class C  & 30   & 0   & 70   \\ \hhline{~*\items{|-}|}
\end{tabular}

\end{document}


You can control the color ranges using the HSB or RGB models and the formulas in compA, compB and compC.

So, for "Autum" (red-yellow) range use:

\pgfmathsetmacro\compA{#1/600} %Component R or H
\pgfmathsetmacro\compB{1} %Component G or S
\pgfmathsetmacro\compC{1} %Component B or B


For "Cool" (cyan-magenta) range set rgb for color model and use:

\pgfmathsetmacro\compA{#1/100}   %Component R or H
\pgfmathsetmacro\compB{1-#1/100} %Component G or S
\pgfmathsetmacro\compC{1}        %Component B or B


For "Black-red" range use:

\pgfmathsetmacro\compA{0} %Component R or H
\pgfmathsetmacro\compB{1} %Component G or S
\pgfmathsetmacro\compC{#1/100} %Component B or B


For "Jet" range use:

\pgfmathsetmacro\compA{0.6666-#1/150} %Component R or H
\pgfmathsetmacro\compB{1}             %Component G or S
\pgfmathsetmacro\compC{1}             %Component B or B


For "Cooper" range use:

\pgfmathsetmacro\compA{0.08+#1/5000} %Component R or H
\pgfmathsetmacro\compB{0.7}          %Component G or S
\pgfmathsetmacro\compC{#1/100}       %Component B or B


For "Gray" range use:

\pgfmathsetmacro\compA{0}      %Component R or H
\pgfmathsetmacro\compB{0} %Component G or S
\pgfmathsetmacro\compC{#1/100}      %Component B or B


Follows a solution used for a paper about a neural network based classifier. In the example, there are 5 classes and the confusion matrix is a good way to illustrate the network performance. The tikz code is not universal, but it accepts easily some customization.

\documentclass[tikz]{standalone}
\usepackage{ifthen}
\usetikzlibrary{matrix,calc}

\begin{document}

%The matrix in numbers
%Horizontal target class
%Vertical output class
\def\myConfMat{{
{1620,  30,  60,   0,  0},  %row 1
{   0,1390, 110,  80,100},  %row 2
{   0,  40,1090,  40,  0},  %row 3
{   0, 350,  30,1020, 90},  %row 4
{   0,  50,  30, 300,800},  %row 5
}}

\def\classNames{{"A","B","C","D","E"}} %class names. Adapt at will

\def\numClasses{5} %number of classes. Could be automatic, but you can change it for tests.

\def\myScale{1.5} % 1.5 is a good scale. Values under 1 may need smaller fonts!
\begin{tikzpicture}[
scale = \myScale,
%font={\scriptsize}, %for smaller scales, even \tiny may be useful
]

\tikzset{vertical label/.style={rotate=90,anchor=east}}   % usable styles for below
\tikzset{diagonal label/.style={rotate=45,anchor=north east}}

\foreach \y in {1,...,\numClasses} %loop vertical starting on top
{
% Add class name on the left
\node [anchor=east] at (0.4,-\y) {\pgfmathparse{\classNames[\y-1]}\pgfmathresult};

\foreach \x in {1,...,\numClasses}  %loop horizontal starting on left
{
%---- Start of automatic calculation of totSamples for the column ------------
\def\totSamples{0}
\foreach \ll in {1,...,\numClasses}
{
\pgfmathparse{\myConfMat[\ll-1][\x-1]}   %fetch next element
\xdef\totSamples{\totSamples+\pgfmathresult} %accumulate it with previous sum
%must use \xdef fro global effect otherwise lost in foreach loop!
}
\pgfmathparse{\totSamples} \xdef\totSamples{\pgfmathresult}  % put the final sum in variable
%---- End of automatic calculation of totSamples ----------------

\begin{scope}[shift={(\x,-\y)}]
\def\mVal{\myConfMat[\y-1][\x-1]} % The value at index y,x (-1 because of zero indexing)
\pgfmathtruncatemacro{\r}{\mVal}   %
\pgfmathtruncatemacro{\p}{round(\r/\totSamples*100)}
\coordinate (C) at (0,0);
\ifthenelse{\p<50}{\def\txtcol{black}}{\def\txtcol{white}} %decide text color for contrast
\node[
draw,                 %draw lines
text=\txtcol,         %text color (automatic for better contrast)
align=center,         %align text inside cells (also for wrapping)
fill=black!\p,        %intensity of fill (can change base color)
minimum size=\myScale*10mm,    %cell size to fit the scale and integer dimensions (in cm)
inner sep=0,          %remove all inner gaps to save space in small scales
] (C) {\r\\\p\%};     %text to put in cell (adapt at will)
%Now if last vertical class add its label at the bottom
\ifthenelse{\y=\numClasses}{
\node [] at ($(C)-(0,0.75)$) % can use vertical or diagonal label as option
{\pgfmathparse{\classNames[\x-1]}\pgfmathresult};}{}
\end{scope}
}
}
%Now add x and y labels on suitable coordinates
\coordinate (yaxis) at (-0.3,0.5-\numClasses/2);  %must adapt if class labels are wider!
\coordinate (xaxis) at (0.5+\numClasses/2, -\numClasses-1.25); %id. for non horizontal labels!
\node [vertical label] at (yaxis) {Output Class};
\node []               at (xaxis) {Target Class};
\end{tikzpicture}

\end{document}


The line:

\multicolumn{1}{c}{} & \multicolumn{1}{c}{Total} & \multicolumn{1}{c}{$a+c$} & \multicolumn{\
1}{c}{$b+d$} & \multicolumn{1}{c}{$N$}\\


needs to be corrected to

\multicolumn{1}{c}{} & \multicolumn{1}{c}{Total} & \multicolumn{1}{c}{$a+c$} & \multicolumn{
1}{c}{$b+d$} & \multicolumn{1}{c}{$N$}\\


in order to compile...

• Hi Christian welcome to the site. Often we don't follow-up with such commentary, to keep things self-contained. Which line in which answer are you writing about ? Also you can click edit under an answer and suggest an edit after a few users review it it would be added to the answer if it is sound. May 31 '15 at 15:13
• When you have enough reputation, you'll be able to leave comments / submit edit suggestions for others' posts. As it stands, I think this answer will be converted to a comment or edit soon. Aside, I don't exactly see a difference except for escaping a space, which is (AFAIK) unnecessary. May 31 '15 at 15:14
• @percusse Take a look at this answer: tex.stackexchange.com/a/20295/17423 to be fair, it does need some work to be a 'good' example. May 31 '15 at 15:16
• @SeanAllred I meant the answer needs to point that out. May 31 '15 at 15:17
• @percusse naturally :) but I want to point out to OP that normally, answers are reserved for complete, self-contained answers. Stuff like this should just be a comment or a straight-up edit. May 31 '15 at 15:17

\documentclass[conference]{IEEEtran}
\usepackage[center]{caption}
\usepackage{multirow}
\usepackage{textcomp}
\usepackage{graphicx}
\begin{document}
\begin{table}[!ht]
\centering
\caption{Confusion Matrix}
\label{sa}
\renewcommand{\arraystretch}{3}
\begin{tabular}{ll|l|l|l|l|l|}

\multicolumn{2}{c}{}&   \multicolumn{5}{c}{Predicted Classes}\\
\multicolumn{2}{c}{}&\multicolumn{5}{c}{{\rotatebox[origin=c]{0}{Fear}
} {\rotatebox[origin=c]{0}{Happy}
} {\rotatebox[origin=c]{0}{Love}
} {\rotatebox[origin=c]{0}{Sad}
} {\rotatebox[origin=c]{0}{Violence}
}}\\
\cline{3-7}
\multirow{5}{*}{{\rotatebox[origin=c]{90}{Actual Classes}
}} &
Fear&0.55 & 0.16 &0.04 & 0.30 & 0.02  \\ \cline{3-7}
&   Happy&0.13 & 0.75 &0.02 & 0.11 & 0.02 \\ \cline{3-7}
&   Love&0.03 & 0.01 &0.91 & 0.00 & 0.01 \\ \cline{3-7}
&   Sad&0.25 & 0.07 &0.01 & 0.58 & 0.01 \\ \cline{3-7}
&   Violence&0.04 & 0.01 &0.02 & 0.00 & 0.94 \\ \cline{3-7}
\end{tabular}
\end{table}
\end{document}