patnr/fm

Fast Marching (FM) method implementation in Matlab and C++

fm's Issues

About errors from mex fm2dc.cpp util.cpp heap.cpp

Hi, Patrick! When I run CompileMexFile.m. The error shows in the following.
/home/users3/fx592/3D eikonal equation/utils.cpp: In function ‘mxArray* myCreateIntScalar()’:
/home/users3/fx592/3D eikonal equation/utils.cpp:129:67: error: cannot convert ‘int*’ to ‘const mwSize* {aka const
long unsigned int*}’ for argument ‘2’ to ‘mxArray* mxCreateNumericArray_730(mwSize, const mwSize*, mxClassID,
mxComplexity)’
return mxCreateNumericArray(1,dimsOfAScalar,mxINT32_CLASS,mxREAL);

I revise the function into the following

mxArray * myCreateIntScalar() {
mwSize dimsOfAScalar[2] = {1,1};
return mxCreateNumericArray(1,dimsOfAScalar,mxINT32_CLASS,mxREAL);
}
I change int into mwSize. Finallly, I can get through it.

Could you confirm and explain this? I just want to make sure.

Thank you
Timothy

Unrecognized function or variable 'fm2dc'.

Hi I am trying to run the example TS_strata.m but I get the following error:

Error in fm (line 208)
[T eFlag] = fm2dc(F,SourcePoints,dy,dx,opts.order);

Error in TS_strata (line 26)
T4 = fm(F,SPs,Dxyz,struct('implementation','C++','order',2));

I am using Matlab 2021b

Inconsistent units in expression

There appears to be a unit issue in the algorithm. The expression "time = min(xmin1, ymin1) + 1/Fij" implies that 1/Fij has the same units as the other quantities, which it does not. A possible correction is time = xmin1 + dx / Fij or time = ymin1 + dy / Fij, depending on whether xmin1 or ymin1 is smaller.

FM/functions/fm2d.m

Line 312 in 029218c

time = min(xmin1, ymin1) + 1/Fij;

Ray trace not finding the right path

Hi, I am running the following code (based on TS_maze.m example). It is a medium with varying velocity at the layers. The wavefields are calculated nicely. However, the ray trace function doesn't find the travelled path between the source and the receiver. I am I missing something?
The code is attached below.

`% code source: https://github.com/patnr/FM
%% Inputs
clc; clear;
addpath('./functions'); % Add path of functions for FMM
%% Meshing
h = 0.0041; % Step h
nx = 161; % Depth (z) nodes #
nz = 166; % Length (x) nodes #
lx = (nx-1)h; % LZ length m
lz = (nz-1)h; % LX Length (m)
%% Anisotropic velocity field
v0 = 1752.85; % Phase velocity
matrix = ones(nx,nz);
th = linspace(-180,180,nx);
alpha = (0.329ones(1,length(th))+ ... %Anisotropy parameter
0.1055cosd(th))./...
(0.329ones(1,length(th))+ 0.1055ones(1,length(th)));

V = (v0./alpha)'.*matrix; % Velocity field
SPs = [83;81]; % Source
RPs = [166;81]; % Receiver

%% Calculations V
T1 = fm(V,SPs,[1 1],struct('implementation','Matlab','order',2));
settings = struct('useFD',1,'stepSize',2);
path1 = rayTrace(T1,SPs,RPs,settings);
%% Plot
figure
contourf(flipud(T1),'DisplayName','Wavefronts');
hold on;
plot(path1(2,:),path1(1,:),'k','LineWidth',1,'DisplayName','Ray path');
plot(RPs(1),RPs(2),'sk','MarkerFaceColor','k','MarkerSize',14,'DisplayName','Receiver')
plot(SPs(1),SPs(2),'ok','MarkerFaceColor','k','MarkerSize',18,'DisplayName','Source')
lgd = legend;
lgd.NumColumns = 1;
lgd.Location='southeast';
hold off;
title('Wave fronts in an anisotropic medium');

`