add v1 v2
v1 + v2
epsilon
(source, destination, length)
dist_from_point o v p
p
o + k * v
gauss m b
m
b
m*X=b
grid_step
move ()
true
nearly_zero f
f
print_sys m b
m * x = b
print_sys_silhouette m b
solve a b
sub v1 v2
v1 - v2