Changing value of custom profile fields

[Chunky Monkey]

Can anyone tell me an easy way to change the value of a member's custom profile field programatically?

That is, if I create a field called Points, how can I programatically update its value? Is there a function I can call such as setCustomProfileField($user_id, $field, $value) or do I have to use database queries?

If I have to use database queries, can anyone tell me how I can make sure I update the right field for the right user? So if the field is called Points, what would the query be for, say user 26?

Thanks!