header.sty

\usepackage{minted}
\usepackage{amsmath,amsthm,amsfonts,amssymb,amscd}
\usepackage{multirow,booktabs}
\usepackage[table]{xcolor}
\usepackage{fullpage}
\usepackage{lastpage}
\usepackage{enumitem}
\usepackage{fancyhdr}
\usepackage{mathrsfs}
\usepackage{wrapfig}
\usepackage{setspace}
\usepackage{calc}
\usepackage{multicol}
\usepackage{cancel}
\usepackage[retainorgcmds]{IEEEtrantools}
\usepackage[margin=3cm]{geometry}
\usepackage{amsmath}

\usepackage{soul} % strikethru

% Tikz arrows to point at equations
\usepackage{tikz}
\usepackage[outline]{contour} % glow around text
\usetikzlibrary{arrows,arrows.meta}
\usetikzlibrary{decorations.markings}
\tikzset{>=latex} % for LaTeX arrow head
\usepackage{xcolor}
\colorlet{Icol}{blue!50!black}
\colorlet{Ccol}{orange!90!black}
\colorlet{Rcol}{green!50!black}
\colorlet{loopcol}{red!90!black!25}
\colorlet{pluscol}{red!60!black}
\colorlet{minuscol}{blue!60!black}
\newcommand\EMF{\mathcal{E}} %\varepsilon}
\contourlength{1.5pt}
\tikzstyle{EMF}=[battery1,l=$x(t)$,invert]
\tikzstyle{internal R}=[R,color=Rcol,Rcol,l=$r$,/tikz/circuitikz/bipoles/length=30pt]
\tikzstyle{loop}=[->,red!90!black!25]
\tikzstyle{loop label}=[loopcol,fill=white,scale=0.8,inner sep=1]
\tikzstyle{thick R}=[R,color=Rcol,thick,Rcol,l=$R$]
\tikzstyle{thick C}=[C,thick,color=Ccol,Ccol,l=$C$]
\tikzstyle{myswitch}=[closing switch,line width=0.3] %-{Latex[length=3]},

\newcommand{\myvoltmeter}[2] 
{  % #1 = name , #2 = rotation angle
  \begin{scope}[transform shape,rotate=#2]
  \draw[thick] (#1)node(){$\mathbf V$} circle (11pt);
  \draw[rotate=45,-latex] (#1)  +(-17pt,0) --+(17pt,0);
  \end{scope}
}
\usetikzlibrary{tikzmark}

\newlength{\tabcont}
\setlength{\parindent}{0.0in}
\setlength{\parskip}{0.05in}
\usepackage{empheq}
\usepackage{framed}
\usepackage[most]{tcolorbox}
\usepackage{xcolor}
\colorlet{shadecolor}{orange!15}
\parindent 0in
\parskip 12pt
\geometry{margin=1in, headsep=0.25in}
\usepackage{hyperref}
\hypersetup{
    colorlinks=true,
    linkcolor=blue,
    filecolor=blue,
    urlcolor=cyan,
}
% To make " match
\usepackage[english]{babel}
\usepackage[autostyle, english = american]{csquotes}
\MakeOuterQuote{"}
% For easy derivatives without the \frac{\mathrm{d}^2 \omega}{\mathrm{d}\theta^2}
\usepackage[thinc]{esdiff} % ex: \diff{f}{x} &\qquad \diff*[4]{g}{t}{t = 1}
\usepackage{tikz}
\usetikzlibrary{positioning}

\usepackage{enumitem} % http://ctan.org/pkg/enumitem
\setlist{nosep}
\setlist[itemize]{topsep=-0.1cm}

% \usepackage{physics} % for derivatives, (e.g. \dv, \pdv)
\usepackage[siunitx]{circuitikz} %[symbols]
% \usepackage{pdfpages} % so [pages={1,2}] works


% code
\usepackage{listings}
\usepackage{color}

\usepackage{makecell}


\definecolor{dkgreen}{rgb}{0,0.6,0}
\definecolor{gray}{rgb}{0.5,0.5,0.5}
\definecolor{mauve}{rgb}{0.58,0,0.82}

\lstset{frame=tb,
  language=Java,
  aboveskip=3mm,
  belowskip=3mm,
  showstringspaces=false,
  columns=flexible,
  basicstyle={\small\ttfamily},
  numbers=none,
  numberstyle=\tiny\color{gray},
  keywordstyle=\color{blue},
  commentstyle=\color{dkgreen},
  stringstyle=\color{mauve},
  breaklines=true,
  breakatwhitespace=true,
  tabsize=3
}
% 

\makeatletter
\pgfkeys{/pgf/grid lines/.initial=2}

\pgfdeclareshape{grid}{
    % inherit most things from the rectangle shape
    \inheritsavedanchors[from=rectangle]
    \inheritanchorborder[from=rectangle]
    \inheritanchor[from=rectangle]{center}
    \inheritanchor[from=rectangle]{north}
    \inheritanchor[from=rectangle]{south}
    \inheritanchor[from=rectangle]{west}
    \inheritanchor[from=rectangle]{east}
    \inheritanchor[from=rectangle]{south east}
    \inheritanchor[from=rectangle]{south west}
    \inheritanchor[from=rectangle]{north east}
    \inheritanchor[from=rectangle]{north west}
    \inheritbackgroundpath[from=rectangle]

    \savedmacro\lines{%
        \pgfmathtruncatemacro\lines{\pgfkeysvalueof{/pgf/grid lines}}%
    }

    % draw the grid
    \beforebackgroundpath{
        % store lower right in xa/ya and upper right in xb/yb
        \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
        \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y

        % compute distance between the lines
        \pgfmathparse{(\the\pgf@xb-\the\pgf@xa)/(\lines + 1)}
        \pgf@xc=\pgfmathresult pt
        \pgfmathparse{(\the\pgf@yb-\the\pgf@ya)/(\lines + 1)}
        \pgf@yc=\pgfmathresult pt

        % draw grid
        \c@pgf@counta=0
        \c@pgf@countb\lines\relax
        \pgf@xb=\pgf@xa
        \advance\pgf@xb\pgf@xc\relax
        \pgfmathloop
            \ifnum\c@pgf@counta<\c@pgf@countb
                \pgfpathmoveto{\pgfpoint{\pgf@xb}{\pgf@ya}}
                \pgfpathlineto{\pgfpoint{\pgf@xb}{\pgf@yb}}
                \advance\c@pgf@counta 1\relax
                \advance\pgf@xb\pgf@xc\relax
        \repeatpgfmathloop
        % set \pgf@xb to the right side
        \c@pgf@counta=0
        \pgf@yb=\pgf@ya
        \advance\pgf@yb\pgf@yc\relax
        \pgfmathloop
            \ifnum\c@pgf@counta<\c@pgf@countb
                \pgfpathmoveto{\pgfpoint{\pgf@xa}{\pgf@yb}}
                \pgfpathlineto{\pgfpoint{\pgf@xb}{\pgf@yb}}
                \advance\c@pgf@counta 1\relax
                \advance\pgf@yb\pgf@yc\relax
        \repeatpgfmathloop
        \pgfusepath{stroke}
    }

    % add anchors for vertices (intersections of grid lines)
    % and center points (centers of the small rectangles).
    %
    % vertex anchors are simply called 'x y' with '0 0' being the lower left
    % vertex.
    % center anchors are called 'center x y' with 'center 1 1' being the center
    % of the lower left rectangle
    \pgfutil@g@addto@macro\pgf@sh@s@grid{%
        \c@pgf@counta\lines
        \advance\c@pgf@counta 1\relax
        \pgfmathloop\ifnum\c@pgf@counta>-1
            {% group to allow nesting of loops
                \c@pgf@countb\lines
                \advance\c@pgf@countb 1\relax
                \pgfmathloop\ifnum\c@pgf@countb>-1
                    \pgfutil@ifundefined{pgf@anchor@grid@\the\c@pgf@counta\space\the\c@pgf@countb}{%
                        % need to use xdef, so that \c@pgf@counta/b are expanded
                        % vertices
                        \expandafter\xdef\csname pgf@anchor@grid@\the\c@pgf@counta\space\the\c@pgf@countb\endcsname{%
                            \noexpand\southwest \noexpand\pgf@xa=\noexpand\pgf@x \noexpand\pgf@ya=\noexpand\pgf@y
                            \noexpand\northeast \noexpand\pgf@xb=\noexpand\pgf@x \noexpand\pgf@yb=\noexpand\pgf@y
                            \noexpand\pgfmathparse{(\noexpand\the\noexpand\pgf@xb-\noexpand\the\noexpand\pgf@xa)/(\noexpand\lines + 1)*\the\c@pgf@counta}
                            \noexpand\pgf@x=\noexpand\pgf@xa\noexpand\relax
                            \noexpand\advance\noexpand\pgf@x\noexpand\pgfmathresult pt\noexpand\relax
                            \noexpand\pgfmathparse{(\noexpand\the\noexpand\pgf@yb-\noexpand\the\noexpand\pgf@ya)/(\noexpand\lines + 1)*\the\c@pgf@countb}
                            \noexpand\pgf@y=\noexpand\pgf@ya\noexpand\relax
                            \noexpand\advance\noexpand\pgf@y\noexpand\pgfmathresult pt\noexpand\relax
                        }
                        % centers
                        \expandafter\xdef\csname pgf@anchor@grid@center\space\the\c@pgf@counta\space\the\c@pgf@countb\endcsname{%
                            \noexpand\southwest \noexpand\pgf@xa=\noexpand\pgf@x \noexpand\pgf@ya=\noexpand\pgf@y
                            \noexpand\northeast \noexpand\pgf@xb=\noexpand\pgf@x \noexpand\pgf@yb=\noexpand\pgf@y
                            \noexpand\pgfmathparse{(\noexpand\the\noexpand\pgf@xb-\noexpand\the\noexpand\pgf@xa)/(2*(\noexpand\lines + 1))*(2*\the\c@pgf@counta-1)}
                            \noexpand\pgf@x=\noexpand\pgf@xa\noexpand\relax
                            \noexpand\advance\noexpand\pgf@x\noexpand\pgfmathresult pt\noexpand\relax
                            \noexpand\pgfmathparse{(\noexpand\the\noexpand\pgf@yb-\noexpand\the\noexpand\pgf@ya)/(2*(\noexpand\lines + 1))*(2*\the\c@pgf@countb-1)}
                            \noexpand\pgf@y=\noexpand\pgf@ya\noexpand\relax
                            \noexpand\advance\noexpand\pgf@y\noexpand\pgfmathresult pt\noexpand\relax
                        }
                    }{\c@pgf@countb0\relax}
                    \advance\c@pgf@countb-1\relax
                \repeatpgfmathloop
            }
            \advance\c@pgf@counta-1\relax
        \repeatpgfmathloop
    }
}
\makeatother

\theoremstyle{definition}
\newtheorem{defn}{Definition}
\newtheorem{reg}{Rule}
\newtheorem{exer}{Exercise}
\newtheorem{note}{Note}

% imp box
\usepackage{xcolor,mdframed}
\newenvironment{important}[1][]{%
   \begin{mdframed}[%
      backgroundcolor={red!15}, hidealllines=true,
      skipabove=0.7\baselineskip, skipbelow=0.7\baselineskip,
      splitbottomskip=2pt, splittopskip=4pt, #1]%
   \makebox[0pt]{% ignore the withd of !
      \smash{% ignor the height of !
         \fontsize{32pt}{32pt}\selectfont% make the ! bigger
         \hspace*{-19pt}% move ! to the left
         \raisebox{-2pt}{% move ! up a little
            {\color{red!70!black}\sffamily\bfseries !}% type the bold red !
         }%
      }%
   }%
}{\end{mdframed}}
% imp box

\usepackage{pdfpages}