Headings change influence the caption formatting (srcreprt)

Question

I had to change the headings (chapter, sections, subsections...) for a journal to get a final point after the last number. Example:

1 My First Chapter 
1. My first Chapter

Therefore, I added the following stuff to my preamble:

\renewcommand{\thechapter}{\arabic{chapter}.}
\renewcommand{\thesection}{\thechapter\arabic{section}.}
\renewcommand{\thesubsection}{\thesection\arabic{subsection}.}

The problem that I have now is, that the captions of the figures and tables, and also the references are not correct anymore because I got the additional point:

\caption{Evaluation of the arbitrary temperature profiles on $n$ random points (red)}

Will be displayed as:

Figure 2..2: Evaluation of the arbitrary temperature profiles on n random points (red)

As you can, I got the additional point between the numbers, which comes from the added lines above. Based on the feedback I got, I checked out the following thread: How to add a dot after the section number? , which is finally what I am searching for but the commands:

\titlelabel{\thetitle.}

Is not working within my class (scrreprt}. Doing so, I get the error message:

Undefined control sequence \section{Latex}

At the moment I do not know how to change this behavior. Any suggestion is warmly welcomed.

By the way, to all supporters and volunteers, you do a really great work.!

Answer 1

That is normal: you changed the way the chapter, section, &c. counters are displayed. Likewise, for cross references, you'd obtain things like ‘We've seen in Chapter 1. that …’ instead of ‘We've seen in Chapter 1 that …’. A simple way to obtain a dot only in chapter, section, &c. titles, is to load titlesec(if compatible with your class) and in the preamble:

\usepackage{titlesec}
\titlelabel{\thetitle. }