Boot problem on dual-boot MacBook Pro Can anyone help me restore the original boot 'order' on my Mac, using command-line? 

I wanted to install Ubuntu on my Macbook Pro Retina (early 2013), so I could run some specific software I needed for my work. I followed the instructions from this site: http://www.makeuseof.com/tag/install-linux-macbook-pro/

I managed to install Ubuntu on a small partition on my HD, and then I performed 'efiboot fix', as suggested, so I could boot Ubuntu after restarting my Mac. I ran the following commands in Ubuntu: 

sudo apt-get install efibootmgr
sudo efibootmgr
sudo efibootmgr -o 0,80


Then I restarted my Mac, but neither Ubuntu nor OS X could boot normally. Basically, I got a blank screen. I restarted again, holding the alt key, and then I was able to choose to boot OS X. 

Can I revert the boot order somehow, using Terminal commands in OS X? Really don't feel like experimenting again with Ubuntu. And can I remove this disk partition with Ubuntu now? I tried to do it through Disk Utility, but it's not possible. Any help will be greatly appreciated.
Since you can boot into OS X by holding down the Option key and selecting your OS X partition, you just need to set the Startup Partition in System Preferences.

How do I set OS X to boot by default?

This will be persistent across reboots.