S05001

Error Code

S05001

Error Message

A set does not support random access. RefId:S05001

Probable Causes

The set in DolphinDB is implemented using a hash table, which does not support random access. This error occurs when attempting to access a set using index or iterating over it with a for loop.

For example:

x=set(4 5 5 2 3 11 6)
// Accessing a set using an index
x[0]
// Iterating over a set with a for loop
for (i in x) {}

Solutions

• Check if an element exist in a set with the in operator:

  x = set(1 2 3)
  1 in x  // true
  [1,3,4] in x  // [true, true, false] 

• To iterate over the elements of a set, first convert it to a vector with the keys function:

  x = set(1 2 3)
  for (i in x.keys()) {
  }