X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Fcontribs%2Fng_assembly%2Fnum%2Fexadecim.ma;h=1951578a4e656ce477c48f2843eaba6f37649f83;hb=e880d6eab5e1700f4a625ddcd7d0fa8f0cce2dcc;hp=9400d90741ef7b6130c109f048a68331b349f109;hpb=ced2abc1e3fe84d5bbfa9ccb2ebf46f253279ebe;p=helm.git

diff --git a/helm/software/matita/contribs/ng_assembly/num/exadecim.ma b/helm/software/matita/contribs/ng_assembly/num/exadecim.ma
index 9400d9074..1951578a4 100755
--- a/helm/software/matita/contribs/ng_assembly/num/exadecim.ma
+++ b/helm/software/matita/contribs/ng_assembly/num/exadecim.ma
@@ -1406,6 +1406,11 @@ ndefinition compl_ex ≝
  | x8 ⇒ x8 | x9 ⇒ x7 | xA ⇒ x6 | xB ⇒ x5
  | xC ⇒ x4 | xD ⇒ x3 | xE ⇒ x2 | xF ⇒ x1 ].
 
+(* operatore abs *)
+ndefinition abs_ex ≝
+λe:exadecim.match getMSB_ex e with
+ [ true ⇒ compl_ex e | false ⇒ e ].
+
 (* operatore x in [inf,sup] o in sup],[inf *)
 ndefinition inrange_ex ≝
 λx,inf,sup:exadecim.