[hackers] [libzahl] refsheet: zgcd: a < 0 also if b < 0 and c == 0 or c < 0 and b == 0, so just if, not iff || Mattias Andrée

[git]

commit 9049bbbf46dff93878a27179f811e2684e3add6d
Author:     Mattias Andrée <maand...@kth.se>
AuthorDate: Sun May 1 01:35:38 2016 +0200
Commit:     Mattias Andrée <maand...@kth.se>
CommitDate: Sun May 1 01:35:38 2016 +0200

    refsheet: zgcd: a < 0 also if b < 0 and c == 0 or c < 0 and b == 0, so just 
if, not iff
    
    Signed-off-by: Mattias Andrée <maand...@kth.se>

diff --git a/doc/refsheet.tex b/doc/refsheet.tex
index 38ed825..fd63291 100644
--- a/doc/refsheet.tex
+++ b/doc/refsheet.tex
@@ -137,7 +137,7 @@ Unless specified otherwise, all times are of type {\tt 
z\_t}.
 \entry    {zodd(a)}           {Is $a$ odd?}            {returns {\tt int} 1 
(true) or 0 (false)}
 \entry    {zodd\_nonzero(a)}  {Is $a$ odd?}            {ditto, assumes $a \neq 
0$}
 \entry    {zzero(a)}          {Is $a$ zero?}           {returns {\tt int} 1 
(true) or 0 (false)}
-\entry    {zgcd(a, b, c)}     {$a \gets \gcd(c, b)$}   {$a < 0$ iff $b < 0 
\wedge c < 0$}
+\entry    {zgcd(a, b, c)}     {$a \gets \gcd(c, b)$}   {$a < 0$ if $b < 0 
\wedge c < 0$}
 \entryFive{zptest(a, b, c)}   {Is $b$ a prime?}        {{\tt c} runs of 
Miller--Rabin, returns}
                                                        {{\tt enum zprimality} 
{\tt NONPRIME} (0)}
                                                        {(and stores the 
witness in {\tt a} unless}