虽然我使用的是 circuitikz,但我无法在简单的电路中绘制欧姆表。如果我用电压表或电流表代替欧姆表,它可以正常工作,否则则不行。另外,万用表有符号吗?
我的电路是
\begin{circuitikz}[american]
\draw
(0,0) to[battery] (0,4)
(0,4) to[short, o-o] (2,4)
(2,0) to[short,o-o] (0,0)
(3,4) to[R, o-o] (3,0)
(3,4) -- (4,4)
to[ohmmeter] (4,0)
(4,0) to[short,o-o] (3,0)
\end{circuitikz}
答案1
ohmmeter
虽然它在文档中,但似乎没有定义。但是,由于除了文本字母外ohmmeter
与 相同voltmeter
,因此您可以按如下方式定义符号。
\documentclass[border={5pt}]{standalone}
\usepackage[american voltages,siunitx]{circuitikz}
\makeatletter
\def\pgf@circ@myvoltmeter@path#1{\pgf@circ@bipole@path{myvoltmeter}{#1}}
\tikzset{ohmmeter/.style = {\circuitikzbasekey, /tikz/to
path=\pgf@circ@myvoltmeter@path}}
\pgfcircdeclarebipole{}{\ctikzvalof{bipoles/voltmeter/height}}{myvoltmeter}
{\ctikzvalof{bipoles/voltmeter/height}}{\ctikzvalof{bipoles/voltmeter/width}}
{
\def\pgf@circ@temp{right}
\ifx\tikz@res@label@pos\pgf@circ@temp
\pgf@circ@res@step=-1.2\pgf@circ@res@up
\else
\def\pgf@circ@temp{below}
\ifx\tikz@res@label@pos\pgf@circ@temp
\pgf@circ@res@step=-1.2\pgf@circ@res@up
\else
\pgf@circ@res@step=1.2\pgf@circ@res@up
\fi
\fi
\pgfpathmoveto{\pgfpoint{\pgf@circ@res@left}{\pgf@circ@res@zero}}
\pgfpointorigin \pgf@circ@res@other = \pgf@x
\advance \pgf@circ@res@other by -\pgf@circ@res@up
\pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{\pgf@circ@res@zero}}
\pgfusepath{draw}
\pgfsetlinewidth{\pgfkeysvalueof{/tikz/circuitikz/bipoles/thickness}
\pgfstartlinewidth}
\pgfscope
\pgfpathcircle{\pgfpointorigin}{\pgf@circ@res@up}
\pgfusepath{draw}
\endpgfscope
\pgfsetlinewidth{\pgfstartlinewidth}
\pgftransformrotate{90} % rotate the label
\pgfpathmoveto{\pgfpoint{-\pgf@circ@res@other}{.8\pgf@circ@res@up}}
\pgfpathlineto{\pgfpoint{\pgf@circ@res@other}{.8\pgf@circ@res@down}}
\pgfusepath{draw}
\pgfnode{circle}{center}{\textbf{\Large \si{\ohm}}}{}{}
\pgfscope
\pgftransformshift{\pgfpoint{-\pgf@circ@res@other}{.8\pgf@circ@res@up}}
\pgftransformrotate{45}
\pgfnode{currarrow}{center}{}{}{\pgfusepath{stroke}}
\endpgfscope
\pgfpathmoveto{\pgfpoint{-\pgf@circ@res@other}{\pgf@circ@res@zero}}
\pgfpathlineto{\pgfpoint{\pgf@circ@res@right}{\pgf@circ@res@zero}}
\pgfusepath{draw}
\pgfusepath{stroke}
}
\makeatother
\begin{document}
\begin{circuitikz}[thick]
\draw
(0,4) to[battery] (0,0)
(0,4) to[short, o-o] (2,4)
(2,0) to[short,o-o] (0,0)
(3,4) to[R, o-o] (3,0)
(3,4) -- (4,4) to[ohmmeter](4,0);
\end{circuitikz}
\end{document}
结果是
答案2
只是为了好玩:
\documentclass{standalone}
\usepackage{circuitikz}
\makeatletter
% ************************* analog meter **************************
\ctikzset{bipoles/meter/height/.initial=.80}
\ctikzset{bipoles/meter/width/.initial=.80}
\ctikzset{bipoles/meter/logo/.initial=$\Omega$}
\pgfcircdeclarebipole{}
{\ctikzvalof{bipoles/meter/height}}
{meter}
{\ctikzvalof{bipoles/meter/height}}
{\ctikzvalof{bipoles/meter/width}}
{
\pgfsetlinewidth{\pgfkeysvalueof{/tikz/circuitikz/bipoles/thickness}\pgfstartlinewidth}
\pgfextractx{\pgf@circ@res@right}{\northeast}
\pgfextractx{\pgf@circ@res@left}{\southwest}
\pgfextracty{\pgf@circ@res@up}{\northeast}
\pgfextracty{\pgf@circ@res@down}{\southwest}
%
\pgfpathellipse{\pgfpointorigin}{\pgfpoint{0}{\pgf@circ@res@up}}{\pgfpoint{\pgf@circ@res@left}{0}}
\pgfusepath{draw}
\pgfpathcircle{\pgfpointorigin}{2\pgfstartlinewidth}
\pgfusepath{fill}
\pgfscope
\pgfsetlinewidth{\pgfstartlinewidth}
\pgftransformrotate{-\pgf@circ@direction}
\pgfmoveto{\pgfpoint{0.7\pgf@circ@res@left}{0}}
\pgflineto{\pgfpoint{0.9\pgf@circ@res@left}{0}}
\pgfmoveto{\pgfpoint{0.566\pgf@circ@res@left}{0.411\pgf@circ@res@up}}
\pgflineto{\pgfpoint{0.728\pgf@circ@res@left}{0.529\pgf@circ@res@up}}
\pgfmoveto{\pgfpoint{0.216\pgf@circ@res@left}{0.666\pgf@circ@res@up}}
\pgflineto{\pgfpoint{0.278\pgf@circ@res@left}{0.856\pgf@circ@res@up}}
\pgfmoveto{\pgfpoint{0.216\pgf@circ@res@right}{0.666\pgf@circ@res@up}}
\pgflineto{\pgfpoint{0.278\pgf@circ@res@right}{0.856\pgf@circ@res@up}}
\pgfmoveto{\pgfpoint{0.566\pgf@circ@res@right}{0.411\pgf@circ@res@up}}
\pgflineto{\pgfpoint{0.728\pgf@circ@res@right}{0.529\pgf@circ@res@up}}
\pgfmoveto{\pgfpoint{0.7\pgf@circ@res@right}{0}}
\pgflineto{\pgfpoint{0.9\pgf@circ@res@right}{0}}
\pgfusepath{draw}
\endpgfscope
\pgfscope
\pgftransformrotate{-\pgf@circ@direction}
\pgfsetarrowsend{latex}
\pgfmoveto{\pgfpointorigin}
%\pgfmoveto{\pgfpoint{.1414\pgf@circ@res@left}{.1414\pgf@circ@res@up}}
\pgflineto{\pgfpoint{.6363\pgf@circ@res@left}{.6363\pgf@circ@res@up}}
\pgfusepath{draw}
\endpgfscope
\pgfscope
\pgftransformrotate{-\pgf@circ@direction}
\pgftransformyshift{0.5\pgf@circ@res@down}
\pgftext{\ctikzvalof{bipoles/meter/logo}}
\endpgfscope
}
% create meter to-path style
\def\meterpath#1{\pgf@circ@bipole@path{meter}{#1}}
\compattikzset{meter/.style = {\circuitikzbasekey, /tikz/to path=\meterpath, \circuitikzbasekey/bipole/is voltage=true, v=#1}}
\makeatother
\begin{document}
\begin{circuitikz}
\draw (0,0) to[meter,o-*] (2,0);
\draw (3,-1) to[meter,o-*] (3,1);
\end{circuitikz}
\end{document}
\ctikzset{bipoles/meter/logo=Amp}
顺便说一句,您可以使用例如来更改徽标。