How can I make font size look consistent in pgfplots

Question

I've used pfgplot to plot the data as shown in output image. It seems to have isconsistency in font size. Even if not how can i reduce the size of subscript "I" and "R".

\documentclass{standalone}
\usepackage{amsmath}
\usepackage{pgfplots}


\begin{document}
\begin{tikzpicture}[scale = 1]
    \begin{axis}[
            axis x line = middle,
            axis y line = middle,
            xlabel  = {$t$},
            ylabel = {$x_{R}(t)$},
            every axis x label/.style={
                at={(ticklabel* cs:1)},
                anchor=west,
            },
            every axis y label/.style={
                at={(ticklabel* cs:1)},
                anchor=south,
            },
            font = \tiny,
            xmin = 0,
            xmax = 12,
            enlarge x limits = 0.15,
            axis line style = {very thin},
            ymin = -2,
            ymax = 2,
            xtick = {\empty},
            ytick = {\empty},
            extra x ticks={7},
            extra x tick labels={$\tau$},
            axis line style = {black},
            width = 7cm,
            height = 4cm,
            mark size = 1pt,
            ]
\addplot[black,smooth]table{Real.txt};
\addplot [only marks,samples at={7},inner sep=2pt] {1.2} node[pin=0:{$x_{R}(\tau)$}]{};
\addplot [no marks,dashed]coordinates {(7,0)(7,1.2)};
    \end{axis}
\end{tikzpicture}


\begin{tikzpicture}[scale = 1]
\begin{axis}[
axis x line = middle,
axis y line = middle,
xlabel  = {$t$},
ylabel = {$x_{I}(t)$},
every axis x label/.style={
    at={(ticklabel* cs:1)},
    anchor=west,
},
every axis y label/.style={
    at={(ticklabel* cs:1)},
    anchor=south,
},
font = \tiny,
xmin = 0,
xmax = 12,
enlarge x limits = 0.15,
axis line style = {very thin},
ymin = -2,
ymax = 2,
xtick = {\empty},
ytick = {\empty},
extra x ticks={7},
extra x tick labels={$\tau$},
axis line style = {black},
width = 7cm,
height = 4cm,
mark size = 1pt,
]
\addplot[black]table{Imag.txt};
\addplot [only marks,samples at={7},inner sep=2pt] {1} node[pin=0:{$x_{I}(\tau)$}]{};
\addplot [no marks,dashed]coordinates {(7,0)(7,1)};
\end{axis}
\end{tikzpicture}
\end{document}

I think this has nothing to do with pgfplots. Are you happy when you use $x_R$ (in \tiny) in the main text (outside of tikzpicture)? — Dr. Manuel Kuehner, Jan 29 '18 at 20:35
@Dr.ManuelKuehner, No I want R and I to be a little bit smaller in size. — Meet, Jan 29 '18 at 20:38
If lowercase x is really the only option I see your problem... But if the choice is yours you can just use an uppercase X that seems perfect to me. (Just an idea in case you could change it) (Also your example doesn't compile and you have just to remove not needed parts or to add the files missing using filecontents) — koleygr, Jan 29 '18 at 20:51
I also found this that seems related if not a duplicate (since I agree with the comment of @Dr.ManuelKuehner): https://tex.stackexchange.com/questions/212067/subscripts-with-capital-letter-adjusting-or-etiquette — koleygr, Jan 29 '18 at 20:54
@koleygr no the issue there is about capitals not looking that small, but here R really isn't small at all as subscripts are being set at the same size as the base. — David Carlisle, Jan 29 '18 at 21:25
Thanks @DavidCarlisle... I will leave the comment there since it is related but not (finally) a duplicate — koleygr, Jan 29 '18 at 21:28

score 2 · Accepted Answer · answered Jan 29 '18 at 20:59

If you use

\documentclass{article}

\begin{document}

\tiny
$x_R$

\end{document}

Then the R looks big as both x and R at 5pt

Because latex has

 \DeclareMathSizes{5}{5}{5}{5}

so if you add

 \DeclareMathSizes{5}{5}{3}{3}

then it will use 3pt text (pity your reader:-) except that computer modern will give the warning

LaTeX Font Warning: Font shape `OML/cmm/m/it' in size <3> not available
(Font)              size <5> substituted on input line 7.

So add

\RequirePackage{fix-cm}

to allow any size

\RequirePackage{fix-cm}
\documentclass{article}
\DeclareMathSizes{5}{5}{3}{3}

\begin{document}

\tiny
$x_R$

\end{document}

How can I make font size look consistent in pgfplots

1 Answers1