\function{assoc_delete_key} \synopsis{Delete a key from an Associative Array} \usage{assoc_delete_key (Assoc_Type a, String_Type k)} \description The \var{assoc_delete_key} function deletes a key given by \var{k} from the associative array \var{a}. If the specified key does not exist in \var{a}, then this function has no effect. \seealso{assoc_key_exists, assoc_get_keys} \done \function{assoc_get_keys} \synopsis{Return all the key names of an Associative Array} \usage{String_Type[] assoc_get_keys (Assoc_Type a)} \description This function returns all the key names of an associative array \var{a} as an ordinary one dimensional array of strings. If the associative array contains no keys, an empty array will be returned. \example The following function computes the number of keys in an associative array: #v+ define get_num_elements (a) { return length (assoc_get_keys (a)); } #v- \seealso{assoc_get_values, assoc_key_exists, assoc_delete_key, length} \done \function{assoc_get_values} \synopsis{Return all the values of an Associative Array} \usage{Array_Type assoc_get_keys (Assoc_Type a)} \description This function returns all the values in the associative array \var{a} as an array of proper type. If the associative array contains no keys, an empty array will be returned. \example Suppose that \var{a} is an associative array of type \var{Integer_Type}, i.e., it was created via #v+ variable a = Assoc_Type[Integer_Type]; #v- The the following may be used to print the values of the array in ascending order: #v+ static define int_sort_fun (x, y) { return sign (x - y); } define sort_and_print_values (a) { variable i, v; v = assoc_get_values (a); i = array_sort (v, &int_sort_fun); v = v[i]; foreach (v) { variable vi = (); () = fprintf (stdout, "%d\n", vi); } } #v- \seealso{assoc_get_values, assoc_key_exists, assoc_delete_key, array_sort} \done \function{assoc_key_exists} \synopsis{Check to see whether a key exists in an Associative Array} \usage{Integer_Type assoc_key_exists (Assoc_Type a, String_Type k)} \description The \var{assoc_key_exists} function may be used to determine whether or not a specified key \var{k} exists in an associative array \var{a}. It returns \1 if the key exists, or \0 if it does not. \seealso{assoc_get_keys, assoc_get_values, assoc_delete_key} \done