// building the file

// chdir('mypath');
t = linspace(0, 2*%pi, 100);
X = cos(t)';
Y = sin(t)';
Z = cos(3*t)';

write('test.txt', [X, Y, Z]);

// clearing the variables

clear;

// reading the file

// chdir('mypath');
M = read('test.txt', -1, 3);
X = M(:,1);
Y = M(:,2);
Z = M(:,3);

// 3d plotting

param3d(X, Y, Z)