1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Vector notation

  1. Apr 17, 2010 #1
    1. The problem statement, all variables and given/known data
    Hi guys

    If I have a vector v, then is it correct notation to write

    \mathbf v =
    \left( {\begin{array}{*{20}c}
    {v_1 } \\
    {v_2 } \\
    \end{array}} \right) = (v_1,v_2)^T,

    where T is the transpose?
  2. jcsd
  3. Apr 17, 2010 #2
    Yes. Although you can write a vector as either a row or a column, the usual convention is to treat the column form as more basic:

    [tex]x = \begin{pmatrix} x_1\\ x_2 \end{pmatrix}[/tex]

    [tex]x^T = \begin{pmatrix}x_1 & x_2 \end{pmatrix}[/tex]

    so that the dot product [itex]\textbf{x} \cdot \textbf{y}[/itex] is usually expressed in matrix form as

    [tex]x^T y = \begin{pmatrix}x_1 & x_2 \end{pmatrix} \begin{pmatrix} y_1 \\ y_2 \end{pmatrix}[/tex]
  4. Apr 17, 2010 #3
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook