contmech.sty

\RequirePackage{mathtools}
\RequirePackage{amssymb}

% The common binary operators
\newcommand{\dprodt}{\mathbin{\cdot\cdot}} % Double product transpose
\newcommand{\dprod}{\mathbin{\vcentcolon}} % Double product
\newcommand{\cross}{\mathbin{\times}} % Cross product
\newcommand{\outerp}{\mathbin{\otimes}} % Outer product
\newcommand{\uouterp}{\mathbin{\overline{\otimes}}} % Upper outer product
\newcommand{\louterp}{\mathbin{\underline{\otimes}}} % Lower outer product

% Tensors
\newcommand{\ta}[1]{\boldsymbol{#1}} % First order tensor. Bold, cursive
%\newcommand{\ts}[1]{\boldsymbol{\mathrm{#1}}} % Second order tensor. Bold, straigt
\newcommand{\ts}[1]{\boldsymbol{#1}} % Second order tensor. Bold, cursive
\newcommand{\td}[1]{\boldsymbol{\mathcal{#1}}} % Third order tensor. Bold, caligraphy
\newcommand{\tf}[1]{\boldsymbol{\mathsf{#1}}} % Fourth order tensor. Bold, sans-serif

% Alternative commands when using unicode-math.
%\renewcommand{\ta}[1]{\mathbfit{#1}}
%\renewcommand{\ts}[1]{\mathbfit{#1}}
%\renewcommand{\td}[1]{\mathbfcal{#1}}
%\renewcommand{\tf}[1]{\mathbfsf{#1}}

\newcommand{\vect}[1]{\underline{#1}} % Vectors
\newcommand{\mat}[1]{\underline{#1}} % Matrices (even if they are the same, keep them seperate if you ever wish to change it.

\newcommand{\set}[1]{\mathbb{#1}} % For defining sets

\newcommand{\diff}{\ts\nabla} % Very common operator

\newcommand{\majorT}{\mathrm{T}} % For major transpose, \ts A^\Tran
\newcommand{\minorT}{\mathrm{t}} % For minor transpose, \tf A^\tran

% Common decorations for tensors.
\newcommand{\dev}{\mathrm{dev}} % Deviatoric part
\newcommand{\vol}{\mathrm{vol}} % Volumetric part
\newcommand{\sym}{\mathrm{sym}} % Symmetric part
\newcommand{\skw}{\mathrm{skw}} % Skew part
\newcommand{\sph}{\mathrm{sph}} % Spherical part
\newcommand{\trial}{\mathrm{tr}} % Trial value
\newcommand{\el}{\mathrm{e}} % Elastic
\newcommand{\pl}{\mathrm{p}} % Plastic
\newcommand{\eff}{\mathrm{e}} % Effective value
\newcommand{\eqv}{\mathrm{e}} % Equivalent value
\newcommand{\alg}{\mathrm{a}} % Algorithmic value
\newcommand{\mean}{\mathrm{m}} % Mean value
\newcommand{\red}{\mathrm{red}} % Reduced value
\newcommand{\thres}{\mathrm{th}} % Threshold value
\newcommand{\macro}{\mathrm{M}} % Macroscopic value
\newcommand{\fluct}{\mathrm{s}} % Fluctuation
\newcommand{\nominal}{\mathrm{nom}} % Nominal value

\newcommand{\Dissipation}{\mathcal{D}}
\newcommand{\Dirichlet}{\mathrm{D}}
\newcommand{\Neumann}{\mathrm{N}}

% For typing out second order base indicies conveniently
\newcommand{\be}[1]{\ta{e}_{#1}}
\newcommand{\bee}[2]{\ta{e}_{#1}\otimes\ta{e}_{#2}}
\newcommand{\beee}[3]{\ta{e}_{#1}\otimes\ta{e}_{#2}\otimes\ta{e}_{#3}}
\newcommand{\beeee}[4]{\ta{e}_{#1}\otimes\ta{e}_{#2}\otimes\ta{e}_{#3}\otimes\ta{e}_{#4}}

% Outer math commands;
\newcommand{\defeq}{\overset{\mathrm{def}}{=}} % For definitions X \defeq Y + 1
%\newcommand{\defeq}{\coloneqq} % alternative

\newcommand{\nextts}[1]{\prescript{n}{}{#1}} % Next timestep.
\newcommand{\oldts}[1]{\prescript{n-1}{}{#1}} % Old timestep.

%\usepackage{commath} % Defines \op, \od, \md for derivatives. Usefull. Similarly defined as below;

% Differentiation (like with integrals)
\DeclareMathOperator{\dif}{d \!}
\DeclareMathOperator{\Dif}{D \!}
\DeclareMathOperator{\tr}{tr} % Trace

\providecommand{\od}[2]{\ensuremath{\frac{\dif\:#1}{\dif #2}}} % Ordinary derivatives
\providecommand{\pd}[2]{\ensuremath{\frac{\partial\: #1}{\partial #2}}} % Total derivatives
\providecommand{\md}[3]{\ensuremath{\frac{\partial^2\: #1}{\partial #2 \partial #3}}} % Mixed derivatives.

\DeclarePairedDelimiter{\abs}{\lvert}{\rvert} % Norm of a tensor or vector \norm A or \nornm* A
\DeclarePairedDelimiter{\norm}{\lVert}{\rVert} % Absolute value of a scalar \abs x
\DeclarePairedDelimiter{\mcc}{\langle}{\rangle} % McCauley bracket