equations
I am using the following code to have a long linear regression model in my two-column latex file. I have used figure * to avoid the overlapping of the equation with the second column. However, it doesn't look good to me. Could you please suggest me any better way for this.
\begin{figure*}[!t]
\begin{equation}
\label{eq:sf}
ua = (49.3) + (-13 * m\_a) + (-0.4 * k\_a) + (-1 * l\_b) + (8 * t\_b) + (-9 * s\_a)
\end{equation}
\end{figure*}
The best approach would be to introduce some new symbols such as Z=\sin(\theta_3-\theta_2) in order to get it easier to read and shorter to typeset.
Assuming that you need all those terms in one equation, you could possibly do like the following:
% arara: pdflatex
\documentclass[twocolumn]{article}
\usepackage{mathtools}
\usepackage{blindtext}
\begin{document}
\blindtext
\begin{multline*}
J=\frac{-l_2}{\sin(\theta_3-\theta_2)}\cdot \\
\begin{bmatrix}
\begin{split}&\sin(\theta_1)\sin(\theta_3-\theta_2)\\&\quad+\sin(\theta_2)\sin(\theta_1-\theta_3)\end{split}&-\sin(\theta_2)\sin(\theta_4-\theta_3)\\[3ex]
\begin{split}&-\cos(\theta_1)\sin(\theta_3-\theta_2)\\&\quad-\cos(\theta_2)\sin(\theta_1-\theta_3)\end{split}&\cos(\theta_2)\sin(\theta_4-\theta_3)
\end{bmatrix}
\end{multline*}
\blindtext
\end{document}
I would do this with alignedat and \widehat. Also, maybe I'm wrong, but I doubt that SRI and the like denote the product of the three variables S, R, I or Var is the product of V, a, r.
\documentclass{article}
\usepackage{mathtools}
\DeclareMathOperator{\Var}{Var}
\newcommand{\SR}{\mathit{SR}}
\newcommand{\SRI}{\mathit{SRI}}
\begin{document}
\begin{equation}
\begin{alignedat}{2}
\SRI &= P\widehat{P}_x+(1-P)(1-\widehat{P}_x) \\
\Var(\SR) &= m^{-1}\SRI(1-\SRI) \\
\Var(\SRI) &=
m^{-1}(2P-1)^2\widehat{P}_x(1-\widehat{P}_x) & &{}+ m^{-1}(2\widehat{P}_x-1)^2P_y(1-P_y) \\
& & &{}+ 4m^{-2}\widehat{P}_y\widehat{P}_x(1-P_y(1-\widehat{P}_x) \\
P &= m^{-1}\sum_{j=1}^mI(\bar{\sigma }_{t+j})
\end{alignedat}
\end{equation}
\end{document}
Best Answer
I am not sure exactly what the problem is, but does this help:
If you are looking to automatically break the equation that is a bit more complicated, and perhaps the breqn package may be useful to look into.