Method on @sym: tril (A)
Method on @sym: tril (A, k)

Lower-triangular part of a symbolic matrix.

Example:

A = sym([1 2 3; 4 5 6; 7 8 9])
  ⇒ A = (sym 3×3 matrix)
      ⎡1  2  3⎤
      ⎢       ⎥
      ⎢4  5  6⎥
      ⎢       ⎥
      ⎣7  8  9⎦

tril(A)
  ⇒ (sym 3×3 matrix)
      ⎡1  0  0⎤
      ⎢       ⎥
      ⎢4  5  0⎥
      ⎢       ⎥
      ⎣7  8  9⎦

tril(A, 1)
  ⇒ (sym 3×3 matrix)
      ⎡1  2  0⎤
      ⎢       ⎥
      ⎢4  5  6⎥
      ⎢       ⎥
      ⎣7  8  9⎦

See also: @sym/tril.

Package: symbolic