Compile the C++ code in MATLAB to create a MEX file

I downloaded MadgwickAHRS.cpp from Github and want to use it in MATLAB. So, I do not know how to add the Madgwick filter path. The code for that is as follows.

% Add path to Madgwick filter
addpath('MadgwickAHRS'); % Make sure the Madgwick filter is in the MATLAB path

I do not understand the “%” part.

% 変数の初期化
dt = 0.01; %タイムステップ(100Hz) 
pos1 = [0, 0, 0];
pos2 = [0, 0, 0];
vel1 = [0, 0, 0];
vel2 = [0, 0, 0];

% センサーデータの読み込み
data1 = xlsread('ho121移動.xlsx');
data2 = xlsread('ho122移動.xlsx');

% データの抽出
time = dt;
mx1 = data1(:, 2); % 磁気 x
my1 = data1(:, 3); % 磁気 y
mz1 = data1(:, 4); % 磁気 z
ax1 = data1(:, 5)*9.81% 加速度 x
ay1 = data1(:, 6)*9.81; % 加速度 y
az1 = data1(:, 7)*9.81; % 加速度 z
gx1 = data1(:, 8); % 角速度 x
gy1 = data1(:, 9); % 角速度 y
gz1 = data1(:, 10); % 角速度 z
mx2 = data2(:, 2); % 磁気 x
my2 = data2(:, 3); % 磁気 y
mz2 = data2(:, 4); % 磁気 z
ax2 = data2(:, 5)*9.81;% 加速度 x
ay2 = data2(:, 6)*9.81; % 加速度 y
az2 = data2(:, 7)*9.81; % 加速度 z
gx2 = data2(:, 8); % 角速度 x
gy2 = data2(:, 9); % 角速度 y
gz2 = data2(:, 10); % 角速度 z

% Madgwickフィルターへのパスを追加
addpath('MadgwickAHRS'); % MadgwickフィルターがMATLABのパスにあることを確認

% Madgwickフィルターの初期化
AHRS1 = MadgwickAHRS('SamplePeriod', dt, 'Beta', 0.1);
AHRS2 = MadgwickAHRS('SamplePeriod', dt, 'Beta', 0.1);
% 位置を格納する配列
positions1 = zeros(length(time), 3);
positions2 = zeros(length(time), 3);
% センサーフュージョンと位置トラッキングのループ
for i = 1:length(time)
    % 向きの更新
    AHRS1.Update([gx1(i), gy1(i), gz1(i)], [ax1(i), ay1(i), az1(i)], [mx1(i), my1(i), mz1(i)]);
    AHRS2.Update([gx2(i), gy2(i), gz2(i)], [ax2(i), ay2(i), az2(i)], [mx2(i), my2(i), mz2(i)]);
    % 向きのクォータニオンを取得
    quat1 = AHRS1.Quaternion;
    quat2 = AHRS2.Quaternion;
    % 加速度をワールドフレームに回転
    accel1_world = quatrotate(quat1, [ax1(i), ay1(i), az1(i)]);
    accel2_world = quatrotate(quat2, [ax2(i), ay2(i), az2(i)]);
    % 加速度を積分して速度を取得
    vel1 = vel1 + accel1_world * dt;
    vel2 = vel2 + accel2_world * dt;
    % 速度を積分して位置を取得
    pos1 = pos1 + vel1 * dt;
    pos2 = pos2 + vel2 * dt;
    % 位置を格納
    positions1(i, :) = pos1;
    positions2(i, :) = pos2;
end

% 相互距離の計算
distances = sqrt(sum((positions1 - positions2).^2, 2));

% 時間経過とともに各軸の距離をプロット
figure;
plot(time, distances);
xlabel('時間 (s)');
ylabel('距離 (m)');
title('2センサ間の各軸の距離');
grid on;

Answer 1

[Walter Roberson]

addpath('MadgwickAHRS'); % Make sure the Madgwick filter is in the MATLAB path

means that there is a subdirectory of the current folder, by the name of MadgwickAHRS and that the subdirectory is to be added to the MATLAB search path. The effect of adding it to the MATLAB search path is that all of the .m and .mlx and .p and so on files become callable by name.

You need to be a bit careful that MadgwickAHRS is in the current directory at the time the addpath() is called. It can be more robust to provide the full path to MadgwickAHRS in the addpath() call, such as

addpath('/Users/ふた/Documents/MATLAB/MadgwickAHRS')

[ふた]

Thank you for your answer. For example, if the file is located in '/Users/Lid/Documents/MATLAB/MadgwickAHRS', I can just use addpath('/Users/Lid/Documents/MATLAB/MadgwickAHRS');.

One more question, is the same for .cpp?