How to change password by REST API in IIAS?

Summary

You can change password for DB user by REST API in IIAS as follows.

curl -k -u "bluadmin:<bluadmin password>" -H 'Content-Type: application/json' -H
'Accept: text/html' -d '{"id":"<user id>","old_password":"<old password>","new_password":"<new password>"}' -X PUT https://<host url>:<port no>/dashdb-api/v2/users/<user id>

Sample:
[apuser@node0101 ~]$ curl -k -u "bluadmin:bluadmin" -H 'Content-Type: application/json' -H 'Accept: text/html' -d '{"id":"test01","old_password":"Abcdefghij1$","new_password":"Abcde2$fghij"}' -X PUT https://9.xx.xxx.xx:8443/dashdb-api/v2/users/test01
{"password":"************************************************************","metadata":{"updated_at":"20181106080503Z","guid":"test01","created_at":"20181106064557Z","url":"https:\/\/null\/dashdb-api\/v2\/users\/test01"},"role":"bluuser","name":"Testuser","id":"test01","locked":"no","email":"testuser@jp.ibm.com","authentication":{"method":"internal","policy_id":null}}
[apuser@node0101 ~]$