![[attach.png]](idldoc-resources/attach.png)
./
poten_tree.pro
Routines
result = poten_tree(pos, mass [, theta=theta])This function computes the potential energy of a mass distribution.
testtest2test3
Routine details
toppoten_tree
result = poten_tree(pos, mass [, theta=theta])
This function computes the potential energy of a mass distribution. It uses a divide and conquer algorithm based on the Barnes-Hut algorithm, and scales as N(log(N)). The poten_slow program is more accurate, but scales as N^2. Generally, this procedure will calculate energies accurate to 1%
Return value
The potential energy of the system. It is assumed that G=1, so that PE = sum_i (sum j > i (m_i * m_j / r_ij) )
Parameters
- pos in required
A [3, n] array of 3D particle locations
- mass in required
A n element vector of masses
Keywords
- theta in optional
A precision pramater which controls the algorithm. Higher values translate to faster run time and larger errors. A value of 1 is recommended, and usually achieves 1% accuracy. A value of 1.5 achieves 1% accuracy for >100 evenly distributed particles. Default is 1
toptest
test
toptest2
test2
toptest3
test3
File attributes
| Modifcation date: | Mon Jul 26 19:29:01 2010 |
| Lines: | 163 |