code: public Matrix4x3f m11(float m11) {
          this.m11 = m11;
          properties &= ~PROPERTY_ORTHONORMAL;
          if (m11 != 1.0f)
              properties &= ~(PROPERTY_IDENTITY | PROPERTY_TRANSLATION);
          return this;
      }
docs: Set the value of the matrix element at column 1 and row 1.
  
  @param m11
  the new value
  @return this