Data commit

Task/Associative-array-Iteration/RLaB/associative-array-iteration.rlab

@@ -0,0 +1,22 @@
+x = <<>>;  // create an empty list
+x.hello = 1;
+x.world = 2;
+x.["!"] = 3;
+
+// to iterate over identifiers of a list one needs to use the function ''members''
+// the identifiers are returned as a lexicographically ordered string row-vector
+// here    ["!", "hello", "world"]
+for(i in members(x))
+{ printf("%s %g\n", i,  x.[i]); }
+
+// occasionally one needs to check if there exists member of a list
+y = members(x);  // y contains ["!", "hello", "world"]
+clear(x.["!"]);  // remove member with identifier "!" from the list "x"
+for(i in y)
+{ printf("%s %g\n", i,  x.[i]); }  // this produces error because x.["!"] does not exist
+
+for(i in y)
+{
+  if (exist(x.[i]))
+  { printf("%s %g\n", i,  x.[i]); }  // we print a member of the list "x" only if it exists
+}