src/HOL/Matrix/MatrixGeneral.thy
changeset 15485 e93a3badc2bc
parent 15481 fc075ae929e4
child 15488 7c638a46dcbb
equal deleted inserted replaced
15484:2636ec211ec8 15485:e93a3badc2bc
    39   from a have b: "?S \<noteq> {}" by (simp)
    39   from a have b: "?S \<noteq> {}" by (simp)
    40   have c: "finite (?S)" by (simp add: finite_nonzero_positions)
    40   have c: "finite (?S)" by (simp add: finite_nonzero_positions)
    41   from hyp have d: "Max (?S) < m" by (simp add: a nrows_def)
    41   from hyp have d: "Max (?S) < m" by (simp add: a nrows_def)
    42   have "m \<notin> ?S"
    42   have "m \<notin> ?S"
    43     proof -
    43     proof -
    44       have "m \<in> ?S \<Longrightarrow> m <= Max(?S)" by (simp add:Max_le[OF
    44       have "m \<in> ?S \<Longrightarrow> m <= Max(?S)" by (simp add:Max_ge[OF c b])
    45   c b])
       
    46       moreover from d have "~(m <= Max ?S)" by (simp)
    45       moreover from d have "~(m <= Max ?S)" by (simp)
    47       ultimately show "m \<notin> ?S" by (auto)
    46       ultimately show "m \<notin> ?S" by (auto)
    48     qed
    47     qed
    49   thus "Rep_matrix A m n = 0" by (simp add: nonzero_positions_def image_Collect)
    48   thus "Rep_matrix A m n = 0" by (simp add: nonzero_positions_def image_Collect)
    50 qed
    49 qed