xtick latex hour option

Question

I have many graph using date as x axis, and I wonder if there is an option of xtick to put a tick every hour automatically and not writting every tick like that :

xtick = {
{2018-04-27 05:00},
{2018-04-27 06:00},
{2018-04-27 07:00},
{2018-04-27 08:00},
{2018-04-27 09:00},
{2018-04-27 10:00},
{2018-04-27 11:00},
{2018-04-27 12:00},
{2018-04-27 13:00},
{2018-04-27 14:00},
{2018-04-27 15:00},
{2018-04-27 16:00},
{2018-04-27 17:00},
{2018-04-27 18:00},
{2018-04-27 19:00},
{2018-04-27 20:00}
}

Cause I've tried this, that didn't worked and that I know works for years alone :

xtick = {
{2018-04-27 05:00},
{2018-04-27 06:00},
...,
{2018-04-27 20:00}
}

Here is an exemple of what I would like to get in the end :

!https://i.stack.imgur.com/2VJOc.jpg

Thank you !

Answer 1

If only the hour changes, you might want to consider using only the hour as a ticklabel.

---

If you definitely want the entire time/date, you can use the xticklabel option as follows:

\documentclass[tikz,margin=2mm]{standalone}

\usepackage{pgfplots}

\begin{document}
    \begin{tikzpicture}
        \begin{axis}[
            xticklabel = {%
                \pgfmathparse{int(\tick)<10?"0":{},int(\tick)}%
                2018-04-27 \pgfmathresult:00%
            },
            xticklabel style={rotate=90,anchor=east},
            xtick distance=1,
            xmin = 5,
            xmax = 20,
        ]
            \addplot+[domain=5:20] ({x},{x^2});   
        \end{axis}
    \end{tikzpicture}
\end{document}

I used this answer to add a leading zero to the hour.

Result: