How safe is the LA subway?

I just moved to LA and believe or not the subway actually goes between my apartment and places I need to go. I thought great, but when I tried it, I very nearly got into two fist fights by 2 different crazy people who were smashing trash cans, screaming profanities, and trying to pick a fight with anyone on the train. I wasn't even going through any bad neighborhoods.

I have ridden several of the main subway systems in the world, and have never had something like this happen.

Did I just get an abnormal experience? (it was a sunday) or is this common on the LA trains.

Please understand this is not some noob tourist scared of the local "color"- these were both situations that could have gotten pretty violent.

Anyway I'd really like to use the train instead of drive, but if this is a typical day I'll keep polluting in my car.