[Tex/LaTex] How to use fill between package along the y axis

fillbetweentikz-pgf

I am currently wanting to shade the area S_{2} which is the area bounded by the curve y=g(x) and the lines y=10 and y=4. Now, the following code is what I am using but how do you use the fill between function to do this?

\documentclass[]{article}
\usepackage{pgfplots}
\usepackage{mathtools}
\usepackage{cancel}
\usepgfplotslibrary{fillbetween}
\begin{document}
\pgfplotsset{every axis/.append style={
axis x line=middle,    % put the x axis in the middle
axis y line=middle,    % put the y axis in the middle
axis line style={<->}, % arrows on the axis
xlabel={$x$},          % default put x on x-axis
ylabel={$y$},          % default put y on y-axis
ticks=none,
grid=none,
}}
% arrows as stealth fighters
\tikzset{>=stealth}
\begin{center}
\begin{tikzpicture}
\begin{axis}[
xmin=-5,xmax=15,
ymin=-5,ymax=15,
scale=1.5,
transform shape
]
\plot[name path=f1,thick,samples=100,domain=2.1:14.5] {3-2/(x-2)};
\plot[name path=f15,thick,opacity=0,samples=100,domain=2.75:14.5] {0};
\plot[name path=f2,thick,samples=100,domain=-5:2.9] {2+2/(3-x)};
\plot[name path=f25,thick,opacity=0,samples=100,domain=-3:5] {10};
\draw[thick,fill=black,opacity=0.7] (axis cs: 2.67,0) circle (0.7mm);
\draw[thick,fill=black,opacity=0.7] (axis cs: 0,2.67) circle (0.7mm);
%
\addplot fill between[
of = f1 and f15,
soft clip={domain=4:10},
every even segment/.style  = {gray,opacity=.4}
];
%
\addplot fill between[
of = f2 and f25,
soft clip={domain=0:2.75},
every even segment/.style  = {gray,opacity=.4}
];
%%
%,domain y=1:2%
%\draw[style=dashed] (axis cs:1,-20)--(axis cs:1,20);
\node [above] at (axis cs: -0.4,0) {$O$};
\node [above] at (axis cs: 10,3) {$y=f(x)$};
\node [right] at (axis cs: 3,10) {$y=g(x)$};
%
\node [right] at (axis cs: 6,1) {$S_{1}$};
\node [right] at (axis cs: 1,6) {$S_{2}$};
%\\
\node [below] at (axis cs: 10,0) {$x_{1}$};
\node [below] at (axis cs: 4,0) {$4$};
%
\node [left] at (axis cs: 0,4) {$4$};
\node [left] at (axis cs: 0,10) {$y_{1}$};
\end{axis}
\end{tikzpicture}
\end{center}
\end{document}

The following image is what I am getting at the moment.

Any help would be appreciated.

Many thanks!

Best Answer

Very simple: introduce another dummy function f26 with \plot[name path=f26,thick,opacity=0,samples=100,domain=-5:2.9] {2+2/(3-max(x,2))};, and then shade the area between the y-axis, f25 and f26.

\documentclass[]{article}
\usepackage{pgfplots}
\usepackage{mathtools}
\usepackage{cancel}
\usepgfplotslibrary{fillbetween}
\begin{document}
\pgfplotsset{every axis/.append style={
axis x line=middle,    % put the x axis in the middle
axis y line=middle,    % put the y axis in the middle
axis line style={<->}, % arrows on the axis
xlabel={$x$},          % default put x on x-axis
ylabel={$y$},          % default put y on y-axis
ticks=none,
grid=none,
}}
% arrows as stealth fighters
\tikzset{>=stealth}
\begin{center}
\begin{tikzpicture}
\begin{axis}[
xmin=-5,xmax=15,
ymin=-5,ymax=15,
scale=1.5,
transform shape
]
\plot[name path=f1,thick,samples=100,domain=2.1:14.5] {3-2/(x-2)};
\plot[name path=f15,thick,opacity=0,samples=100,domain=2.75:14.5] {0};
\plot[name path=f2,thick,samples=100,domain=-5:2.9] {2+2/(3-x)};
\plot[name path=f26,thick,opacity=0,samples=100,domain=-5:2.9] {2+2/(3-max(x,2))};
\plot[name path=f25,thick,opacity=0,samples=100,domain=-3:5] {10};
\draw[thick,fill=black,opacity=0.7] (axis cs: 2.67,0) circle (0.7mm);
\draw[thick,fill=black,opacity=0.7] (axis cs: 0,2.67) circle (0.7mm);
%
\addplot fill between[
of = f1 and f15,
soft clip={domain=4:10},
every even segment/.style  = {gray,opacity=.4}
];
%
\addplot fill between[
of = f26 and f25,
soft clip={domain=0:2.75},
every even segment/.style  = {gray,opacity=.4}
];
%%
%,domain y=1:2%
%\draw[style=dashed] (axis cs:1,-20)--(axis cs:1,20);
\node [above] at (axis cs: -0.4,0) {$O$};
\node [above] at (axis cs: 10,3) {$y=f(x)$};
\node [right] at (axis cs: 3,10) {$y=g(x)$};
%
\node [right] at (axis cs: 6,1) {$S_{1}$};
\node [right] at (axis cs: 1,6) {$S_{2}$};
%\\
\node [below] at (axis cs: 10,0) {$x_{1}$};
\node [below] at (axis cs: 4,0) {$4$};
%
\node [left] at (axis cs: 0,4) {$4$};
\node [left] at (axis cs: 0,10) {$y_{1}$};
\end{axis}
\end{tikzpicture}
\end{center}
\end{document}

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[Tex/LaTex] Numerical conditional within tikz keys

I am definitely unfamiliar with both beamer and tikz (do not quite get what the \only are supposed to do) but perhaps this could go in the direction you want:

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{chains}
\newcounter{count}

% helper macro:
\long\def\GobToSemiColon #1;{}

\newcommand\myPicture{
\begin{tikzpicture}
  \begin{scope}[start chain = going below]
  \ifnum\value{count}<1 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>3 \expandafter\GobToSemiColon\fi
  \node[draw, rectangle, on chain] {display only when counter is between
    1 and 3};

  \ifnum\value{count}>-1 \expandafter\GobToSemiColon\fi
  \node[draw, rectangle, on chain] {display only when counter is
    negative}; 

  \ifnum\value{count}<100 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>200 \expandafter\GobToSemiColon\fi  
  \node[draw, rectangle, on chain] {display only if counter is between
    100 and 200};

  \ifnum\value{count}<3 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>20 \expandafter\GobToSemiColon\fi
  \node[draw, circle, on chain] {only when counter is in the range 3 to 20};
  \end{scope}
\end{tikzpicture}
}

\begin{document}
\begin{frame}
\only{\setcounter{count}{-3}\myPicture}
\only{\setcounter{count}{105}\myPicture}
\only{\setcounter{count}{39}\myPicture}
\only{\setcounter{count}{2}\myPicture}
\only{\setcounter{count}{5}\myPicture}
\end{frame}
\end{document}

beamer

[Tex/LaTex] TikZ: Drawing an arc from an intersection to an intersection

A solution which allows to draw intersection segments of any two intersections is available as tikz library fillbetween.

This library works as general purpose tikz library, but it is shipped with pgfplots and you need to load pgfplots in order to make it work:

\documentclass{standalone}

\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{fillbetween}

\begin{document}

\begin{tikzpicture}

\draw [name path=red,red] (120:1.06) circle (1.9);
%\draw [name path=yellow,yellow] (0:1.06) circle (2.12);
\draw [name path=green,green!50!black] (0:0.77) circle (2.41);
\draw [name path=blue,blue] (0:0) circle (1.06);

% substitute this temp path by `\path` to make it invisible:
\draw[name path=temp1, intersection segments={of=red and blue,sequence=L1}];
\draw[red,-stealth,ultra thick, intersection segments={of=temp1 and green,sequence=L3}];

\end{tikzpicture}

\end{document}

enter image description here

The key intersection segments is described in all detail in the pgfplots reference manual section "5.6.6 Intersection Segment Recombination"; the key idea in this case is to

create a temporary path temp1 which is the first intersection segment of red and blue, more precisely, it is the first intersection segment in the Left argument in red and blue : red. This path is drawn as thin black path. Substitute its \draw statement by \path to make it invisible.
Compute the desired intersection segment by intersecting temp1 and green and use the correct intersection segment. By trial and error I figured that it is the third segment of path temp1 which is written as L3 (L = left argument in temp1 and green and 3 means third segment of that path).

The argument involves some trial and error because fillbetween is unaware of the fact that end and startpoint are connected -- and we as end users do not see start and end point.

Note that you can connect these path segments with other paths. If such an intersection segment should be the continuation of another path, use -- as before the first argument in sequence. This allows to fill paths segments:

\documentclass{standalone}

\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{fillbetween}

\begin{document}

\begin{tikzpicture}

\draw [name path=red,red] (120:1.06) circle (1.9);
%\draw [name path=yellow,yellow] (0:1.06) circle (2.12);
\draw [name path=green,green!50!black] (0:0.77) circle (2.41);
\draw [name path=blue,blue] (0:0) circle (1.06);

% substitute this temp path by `\path` to make it invisible:
\draw[name path=temp1, intersection segments={of=red and blue,sequence=L1}];
\draw[red,fill=blue,-stealth,ultra thick, intersection segments={of=temp1 and green,sequence=L3}]  
    [intersection segments={of=temp1 and green, sequence={--R2}}]
;

\end{tikzpicture}

\end{document}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] Numerical conditional within tikz keys

[Tex/LaTex] TikZ: Drawing an arc from an intersection to an intersection

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