% chapters, sections, subsections
% fonts: http://www.forkosh.com/pstex/latexcommands.htm
% \titleclass{\chapter}{straight} % make chapter like a section (no newpage)
% \fontsize{size}{spacing}

% "Table 1: Title" -> "Table 1 - Title"
% http://www.peteryu.ca/tutorials/publishing/latex_captions
%\usepackage[font=bf]{caption}   % bold
%

\usepackage{caption}
\DeclareCaptionLabelSeparator{defffis}{ - }
\captionsetup{justification=centering,labelsep=defffis}

% picture and table numbering:   1.1, 1.2 ... 2.1
\renewcommand{\thetable}{\arabic{chapter}.\arabic{table}}
\renewcommand{\thefigure}{\arabic{chapter}.\arabic{figure}}

% headers:
\addto\captionsrussian{\renewcommand\chaptername{}}
% \renewcommand{\thesection}{\thechapter.\arabic{section}}
\renewcommand{\thechapter}{}{}{}
\renewcommand{\thesection}{\arabic{section}}
% \renewcommand{\thesubsection}{\arabic{section}.\arabic{subsection}}

% headers fonts:
\usepackage{hyphenat}   % no hyphens in titles
%\tolerance=1
%\emergencystretch=\maxdimen
%\hyphenpenalty=10000
%\hbadness=10000
%\nohyphens
\newcommand{\mychapterfont}      {\fontsize{22}{26.4}\selectfont}
\newcommand{\mysectionfont}      {\fontsize{20}{18.4}\selectfont}
\newcommand{\mysubsectionfont}   {\fontsize{16}{16.4}\selectfont}
\newcommand{\mysubsubsectionfont}{\fontsize{15}{14.4}\selectfont}
\titleformat{\chapter}[hang]{
  \mychapterfont
  \normalfont
  % \bfseries
  % \mdseries
  % \normalfont
  % \centering            % center on page
  % \it                   % italics
}{\chaptertitlename\ \thechapter}{20pt}{\mychapterfont}% NEW
% {\sizetwelvefixed\MakeUppercase}% NEW
\titlespacing*{\chapter}{-25pt}{0pt}{20pt}


% section
\titleformat{\section}[hang]{
  % \sizetwelvefixed
  % \bfseries
  % \mdseries
  % \normalfont
  % \centering            % center on page
  % \it                   % italics
  \mysectionfont
}{\thesection}{16pt}{\mysectionfont}
% {\sizetwelvefixed\MakeUppercase}% NEW
% \titlespacing*{\section}{-25pt}{0pt}{20pt}


% subsection
\titleformat{\subsection}[hang]{
  % \sizetwelvefixed
  % \bfseries
  % \mdseries
  % \normalfont
  % \centering            % center on page
  % \it                   % italics
  \mysubsectionfont
}{\thesubsection}{16pt}{\mysubsectionfont}
% {\sizetwelvefixed\MakeUppercase}% NEW
% \titlespacing*{\subsection}{-25pt}{0pt}{20pt}

% subsubsection
\titleformat{\subsubsection}[hang]{
  % \sizetwelvefixed
  % \bfseries
  % \mdseries
  % \normalfont
  % \centering            % center on page
  % \it                   % italics
  \mysubsubsectionfont
}{\thesubsubsection}{16pt}{\mysubsubsectionfont}
% {\sizetwelvefixed\MakeUppercase}% NEW
% \titlespacing*{\subsubsection}{-25pt}{0pt}{20pt}


%%\titleclass{\part}{top} % make part like a chapter
%%\titleformat{\part}[hang]% NEW
%%% {\fontfamily{ptm}\large\bfseries\centering}{\chaptertitlename\ \thechapter}{10pt}{\large}% NEW
%%{\sizetwelvefixed\bfseries}{\thepart}{20pt}{\sizetwelvefixed\MakeUppercase}
%%\titlespacing*{\part}{-7pt}{0pt}{20pt}% NEW
%%
%%
%%\makeatletter
%%% \patchcmd{\part}{\if@openright\cleardoublepage\else\clearpage\fi}{}{}{}
%%% \patchcmd{\part}{\if@openright \else \fi}{}{}{}
%%\makeatother
%%\patchcmd{\part}{\null\vfil}{}{}{}       % Part at same page as chapter
%%% \patchcmd{\chapter}{\null\vfil}{}{}{}{}       % Part at same page as chapter
%%\patchcmd{\part}{\partheadstartvskip}{}{}{}



%\setlength{\cftchapindent}{0cm}
%\setlength{\cftchapnumwidth}{0.75cm}
%\setlength{\cftsecnumwidth}{0.5cm}
%\setlength{\cftsubsecnumwidth}{0.95cm}
%\setlength{\cftsubsecindent}{1.25cm}

% \renewcommand{\thechapter}[toc]{}
% \renewcommand{\thesection}[toc]{\arabic{section}}


\usepackage{mathtools}
\DeclarePairedDelimiter\abs{\lvert}{\rvert}%
\DeclarePairedDelimiter\norm{\lVert}{\rVert}%