USING: help.markup help.syntax math math.vectors vectors ;
IN: math.quaternions
+HELP: q+
+{ $values { "u" "a quaternion" } { "v" "a quaternion" } { "u+v" "a quaternion" } }
+{ $description "Add quaternions." }
+{ $examples { $example "USING: math.quaternions prettyprint ;" "{ C{ 0 1 } 0 } { 0 1 } q+ ." "{ C{ 0 1 } 1 }" } } ;
+
+HELP: q-
+{ $values { "u" "a quaternion" } { "v" "a quaternion" } { "u-v" "a quaternion" } }
+{ $description "Subtract quaternions." }
+{ $examples { $example "USING: math.quaternions prettyprint ;" "{ C{ 0 1 } 0 } { 0 1 } q- ." "{ C{ 0 1 } -1 }" } } ;
+
HELP: q*
{ $values { "u" "a quaternion" } { "v" "a quaternion" } { "u*v" "a quaternion" } }
{ $description "Multiply quaternions." }
[ t ] [ qk q>v v>q qk = ] unit-test
[ t ] [ 1 c>q q1 = ] unit-test
[ t ] [ C{ 0 1 } c>q qi = ] unit-test
+[ t ] [ qi qi q+ qi 2 q*n = ] unit-test
+[ t ] [ qi qi q- q0 = ] unit-test
+[ t ] [ qi qj q+ qj qi q+ = ] unit-test
+[ t ] [ qi qj q- qj qi q- -1 q*n = ] unit-test