How to do a karnaugh map?

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How can I draw a Karnaugh map

For an assignment, I have to include a Karnaugh map. The map looks like this:

I'm pretty new to LaTeX, and really have no idea how to do this. I know how to make tables and all, but after hours of looking around, I can't come up with a relatively easy way to do the circles. The closest I've found is this: http://www.ctan.org/tex-archive/macros/latex/contrib/karnaugh, which at least have the same name, but the map looks very different from what mine is supposed to look like. I realize I should include an attempt of solving it, but I really have no idea.

Answer 1

I very slightly modified the answer given by Ignasi here:

https://tex.stackexchange.com/a/36879/14100

to look a little more like what you want. Have a look at the differences between e.g. the karnaugh environment as defined in that answer, versus the modified version here to get a feel for how to change things. If you find this answer useful, then please upvote the answer linked above rather than this one. I personally don't know TikZ at all so I can't help you much more than this unfortunately.

\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{matrix,calc}

%internal group
%#1-space between node and grouping line. Default=0
%#2-top left node
%#3-bottom right node
\newcommand{\implicant}[3][0]{
    \draw[rounded corners=3pt] ($(#2.north west)+(135:#1)$) rectangle ($(#3.south east)+(-45:#1)$);
    }

%group lateral borders
%#1-space between node and grouping line. Default=0
%#2-top left node
%#3-bottom right node
\newcommand{\implicantcostats}[3][0]{
    \draw[rounded corners=3pt] ($(rf.east |- #2.north)+(90:#1)$)-| ($(#2.east)+(0:#1)$) |- ($(rf.east |- #3.south)+(-90:#1)$);
    \draw[rounded corners=3pt] ($(cf.west |- #2.north)+(90:#1)$) -| ($(#3.west)+(180:#1)$) |- ($(cf.west |- #3.south)+(-90:#1)$);
}

%group top-bottom borders
%#1-space between node and grouping line. Default=0
%#2-top left node
%#3-bottom right node
\newcommand{\implicantdaltbaix}[3][0]{
    \draw[rounded corners=3pt] ($(cf.south -| #2.west)+(180:#1)$) |- ($(#2.south)+(-90:#1)$) -| ($(cf.south -| #3.east)+(0:#1)$);
    \draw[rounded corners=3pt] ($(rf.north -| #2.west)+(180:#1)$) |- ($(#3.north)+(90:#1)$) -| ($(rf.north -| #3.east)+(0:#1)$);
}

%group corners
%#1-space between node and grouping line. Default=0
\newcommand{\implicantcantons}[1][0]{
    \draw[rounded corners=3pt] ($(rf.east |- 0.south)+(-90:#1)$) -| ($(0.east |- cf.south)+(0:#1)$);
    \draw[rounded corners=3pt] ($(rf.east |- 8.north)+(90:#1)$) -| ($(8.east |- rf.north)+(0:#1)$);
    \draw[rounded corners=3pt] ($(cf.west |- 2.south)+(-90:#1)$) -| ($(2.west |- cf.south)+(180:#1)$);
    \draw[rounded corners=3pt] ($(cf.west |- 10.north)+(90:#1)$) -| ($(10.west |- rf.north)+(180:#1)$);
}
\def\ol#1{\overline{#1}}
%Empty Karnaugh map 4x4
\newenvironment{Karnaugh}%
{
\begin{tikzpicture}[baseline=(current bounding box.north),scale=0.8]
\draw (0,0) grid (4,4);
%
\matrix (mapa) [matrix of nodes,
        column sep={0.8cm,between origins},
        row sep={0.8cm,between origins},
        every node/.style={minimum size=0.3mm},
        anchor=8.center,
        ampersand replacement=\&] at (0.5,0.5)
{
                       \& |(c00)| $\ol{yw}$  \& |(c01)| $\ol{y}w$  \& |(c11)| $yw$       \& |(c10)| $y\ol{w}$  \& |(cf)| \phantom{00} \\
|(r00)| $\ol{xz}$      \& |(0)|  \phantom{0} \& |(1)|  \phantom{0} \& |(3)|  \phantom{0} \& |(2)|  \phantom{0} \&                     \\
|(r01)| $\ol{x}z$      \& |(4)|  \phantom{0} \& |(5)|  \phantom{0} \& |(7)|  \phantom{0} \& |(6)|  \phantom{0} \&                     \\
|(r11)| $xz$           \& |(12)| \phantom{0} \& |(13)| \phantom{0} \& |(15)| \phantom{0} \& |(14)| \phantom{0} \&                     \\
|(r10)| $x\ol{z}$      \& |(8)|  \phantom{0} \& |(9)|  \phantom{0} \& |(11)| \phantom{0} \& |(10)| \phantom{0} \&                     \\
|(rf) | \phantom{00}   \&                    \&                    \&                    \&                    \&                     \\
};
}%
{
\end{tikzpicture}
}

%Empty Karnaugh map 2x4
\newenvironment{Karnaughvuit}%
{
\begin{tikzpicture}[baseline=(current bounding box.north),scale=0.8]
\draw (0,0) grid (4,2);
%
\matrix (mapa) [matrix of nodes,
        column sep={0.8cm,between origins},
        row sep={0.8cm,between origins},
        every node/.style={minimum size=0.3mm},
        anchor=4.center,
        ampersand replacement=\&] at (0.5,0.5)
{
                      \& |(c00)| $\ol{yz}$  \& |(c01)| $\ol{y}z$  \& |(c11)| $yz$       \& |(c10)| $y\ol{z}$  \& |(cf)| \phantom{00} \\
|(r00)| $\ol{x}$      \& |(0)|  \phantom{0} \& |(1)|  \phantom{0} \& |(3)|  \phantom{0} \& |(2)|  \phantom{0} \&                     \\
|(r01)| $x$           \& |(4)|  \phantom{0} \& |(5)|  \phantom{0} \& |(7)|  \phantom{0} \& |(6)|  \phantom{0} \&                     \\
|(rf) | \phantom{00}  \&                    \&                    \&                    \&                    \&                     \\
};
}%
{
\end{tikzpicture}
}

%Defines 8 or 16 values (0,1,X)
\newcommand{\contingut}[1]{%
\foreach \x [count=\xi from 0]  in {#1}
     \path (\xi) node {\x};
}

%Places 1 in listed positions
\newcommand{\minterms}[1]{%
    \foreach \x in {#1}
        \path (\x) node {1};
}

%Places 0 in listed positions
\newcommand{\maxterms}[1]{%
    \foreach \x in {#1}
        \path (\x) node {0};
}

%Places X in listed positions
\newcommand{\indeterminats}[1]{%
    \foreach \x in {#1}
        \path (\x) node {X};
}

\begin{document}
\begin{Karnaugh}
   \contingut{0,0,0,0,0,1,0,1,1,1,0,0,0,1,0,1}
   \implicant{0}{2}
   \implicantdaltbaix[3pt]{3}{10}
   \implicantcostats{4}{14}
\end{Karnaugh}
%
\begin{Karnaughvuit}
   \minterms{3,4}
   \maxterms{0,1,6,7}
   \indeterminats{2,5}
   \implicant{3}{2}
   \implicant{4}{5}
\end{Karnaughvuit}
\end{document}