how to remove partition on a table?

Suppose I try to setup partition for a large table. because I don't know which way is the better way. So I want to try all of them:

• Range partitioning
• Hash partitioning
• List partitioning
• Round

for my case, with my knowledge, I want to try List and Range firstly, then try Round Robin or Hash.

Looks like if I try list firstly, then I can change partition type to range.

but if I want Round Robin firstly as below:

alter table MyTab partition 4

go

then I try to remove the partition with following way:

alter table MyTab unpartition

go

but there still has one partition remain on MyTab. The partition ID like MyTab_592002109.

How can I remove it completely? then I can try List or Range partition?