Unity2D resize the sprite

I hav sprite 600 * 400 and Pixels Per Unit is 1

It show in the Scene is 600 * 400.

Now,I want to resize my sprite to any size via I input the value in inspector.

For example, I input Width:50 Height:100 then the sprite in Scene is 50 100 I input Width:200 Height:300 then the sprite in Scene is 200 300

I try to use the code "GetComponent ().bounds.size.Set (50f, 100f, 0.2f);"

but it's no use.

How can I implement it?