SCIRun User Mailing List

## [SCIRUN-USERS] Algorithm

• From: Vikas R bhat <vikasraghubhat@gmail.com>
• To: Jess Tate <jess@sci.utah.edu>, scirun-users@sci.utah.edu
• Subject: [SCIRUN-USERS] Algorithm
• Date: Tue, 3 Oct 2017 12:57:17 +0530

Respected Jess,

We have tried to analyse the code of Simulateforwardmagneticfield algorithm.cc found in \scirun4 \src\Packages\BioPSE\Dataflow\Modules\Forward .

I have some simple doubts in this code.

1. I assumed the radius.length() will do sqrt((pt-pt2)^2). Is it correct?

2. I searched the value of constant value mu0 in code, but did not find any (as in description, it says Biot Savart's law is used). Is it possible to include mu0 value using evaluatelinearalgebrageneral. Please help me with this.

We simulated magnetic field on detectors for dipole inside a mesh and took node indices from the show field (show text, show data values). And then tried to solve numerically based on code to analyse.The data impressed on the node is not matching with the solved one. Are we doing anything wrong while solving numerically.

Pls find the attached png and pdf files.

================================================================================================================================

code of the simulateforwardmagfieldalgorithm which we try to analyse,

================================================================================================================================

{

dipmsh_->get_center(pt2, dip_idx);

dipfld_->value(P,dip_idx);

Vector radius = pt - pt2; // detector - source

mag_field += valuePXR / (length * length * length);

}

mag_field *= one_over_4_pi;

magmagfld_->set_value(Dot(mag_field, normal),idx);

magfld_->set_value(mag_field,idx);

================================================================================================================================

================================================================================================================================

--
Thanks,

Vikas.R.Bhat
Contact: +91 9481263176

Attachment: prog.pdf