3

The following MWE

\documentclass[beamer,crop]{standalone}
\usepackage{times}
\usepackage{pgfplots,xparse}

\pgfplotsset{
  compat=1.17, % Specify the compatibility version
  nice_axis/.style={
        xlabel={$t/T_c$},
        ylabel={$p_{BOC \left( 1,1 \right)}\left( t \right)\cdot \sqrt{T_c}$},
        % title={Triangle Function},
        grid=both,
        axis lines=box,
        samples=101,
        domain=-2:2,
        xmin=-1,
        xmax=1,
        ymax=1.2,
        ymin=-1.2,
        ytick={-1, -0.8, ..., 1},
        legend pos=outer north east,
  }
}


\begin{document}


\begin{tikzpicture}
  \begin{axis}[
    nice_axis,
  ]
    \addplot[black, thick, mark=none] coordinates {
        (-1,0)
        (-0.5,0)
        (-0.5,1)
        (0,1)
        (0,-1)
        (0.5,-1)
        (0.5,0)
        (1,0)
    };
  \end{axis}
\end{tikzpicture}


\end{document}

Yields

enter image description here

As far as I could see in in other pots, it is due to roundoff error. How to set ytick so that I don't get the zero-imprecision error? I tried this solution but it seems to work for table only.

Rubem Pacelli
  • 994
  • Could one start at $-5*0.2$ instead of $-1$? – Hagen von Eitzen Nov 01 '23 at 09:04
  • @HagenvonEitzen unfortunately no. Although 0.2 isn't exactly representable, 50.2 rounds to 1.0 exactly. You could say the problem happens in the middle: 0.2 + 0.2 and 0.6 - 0.2 are very* slightly different numbers. – hobbs Nov 01 '23 at 21:17

2 Answers2

6

You can rounded yticklabel by

yticklabel style = {/pgf/number format/fixed},

Complete MWE:

\documentclass[beamer,crop]{standalone}
\usepackage{times}
\usepackage{pgfplots,xparse}

\pgfplotsset{
  compat=1.18, % Specify the compatibility version
  nice_axis/.style={
        xlabel={$t/T_c$},
        ylabel={$p_{BOC \left( 1,1 \right)}\left( t \right)\cdot \sqrt{T_c}$},
 %       title={Pulse Function},
        grid=both,
        axis lines=box,
        domain=-1:1,
        ytick={-1, -0.8, ..., 1},
        yticklabel style = {/pgf/number format/fixed},
        xmin=-1,    xmax=1,
        legend pos=outer north east,
  }
}


\begin{document}


\begin{tikzpicture}
  \begin{axis}[nice_axis]
    \addplot[thick, mark=none] coordinates {
        (-1,0)
        (-0.5,0)
        (-0.5,1)
        (0,1)
        (0,-1)
        (0.5,-1)
        (0.5,0)
        (1,0)
    };
  \end{axis}
\end{tikzpicture}


\end{document}

enter image description here

Zarko
  • 296,517
5

enter image description here

You can use \fpeval to round to 2 decimal places.

Just add

        yticklabel={$\fpeval{0 - round(-\tick,2)}$},

The double negation avoids rounding to -0 in this case.

David Carlisle
  • 757,742