# CalcReorientAngle

## PURPOSE

CALCREORIENTANGLE

## SYNOPSIS

function beta = CalcReorientAngle(vtheta, moves_indx)

## DESCRIPTION

    CALCREORIENTANGLE
       Usage:  beta = CalcReorientAngle(vtheta, moves_indx)

     This function calculates the reorientation angle, or the change in angle
     of progression after the fly stops. The inputs are the angle of the
     velocity vector, vtheta, and an index of all the frames where the fly was
     moving, moves_indx.

## CROSS-REFERENCE INFORMATION

This function calls:

This function is called by:

- FAnalyze FANALYZE

## SOURCE CODE

    0001 function beta = CalcReorientAngle(vtheta, moves_indx)
    0002
    0003 %CALCREORIENTANGLE
    0004 %   Usage:  beta = CalcReorientAngle(vtheta, moves_indx)
    0005 %
    0006 % This function calculates the reorientation angle, or the change in angle
    0007 % of progression after the fly stops. The inputs are the angle of the
    0008 % velocity vector, vtheta, and an index of all the frames where the fly was
    0009 % moving, moves_indx.
    0010
    0011 %Written by Dan Valente
    0012 %modified November 2007
    0013
    0014 m = 1;
    0015 before = 0;
    0016
    0017 for i = 1:length(moves_indx)-1
    0018     if (moves_indx(i)+1 ~= moves_indx(i+1))
    0019         beta(m) = 180*(vtheta(moves_indx(i))-before)/pi;
    0020         if (beta(m) > 180)
    0021             beta(m) = beta(m)-360;
    0022         elseif (beta(m) < -180)
    0023             beta(m) = beta(m)+360;
    0024         end
    0025         before = vtheta(moves_indx(i+1));
    0026         m = m+1;
    0027     end
    0028 end
    0029
    0030 return;