How Yoga Can Help Overcome Anger
I'm very confident that you have been angry at some point in your life and will like as not be angry again. It seems like the right emotion to have when dealing with difficult, threatening or frustrating situations.
My own experience of anger often fills me with shame. When it gets hold of me, I feel utterly powerless, as if possessed by some inner raving werewolf hell-bent on correcting some form of injustice or standing up to some perceived threat. It feels like I've gone temporarily insane. All reason and calmness seem pushed aside by this uncontrollable passion.
When my rage has subsided, I invariably feel humiliated and guilty, wishing to kiss and make up, make reparation, be forgiven and wondering what I can do to avoid loosing my temper again. If you have had the misfortune to experience my ire, I am truly sorry and would like you to know that that I do not get angry willingly and that I am working on it.
Yoga suggests we should practise yoga out of compassion for ourselves, to know the Truth, and for the benefit of all Beings. 
Without doubt, anger is a destructive emotion.
There is a wonderfully helpful bit of advice from Patañjali in this regard. He tells us that:
A sudden desire to act harshly, or encourage or approve harsh actions can be contained by reflecting on the harmful consequences. Often such actions are the results of lower instincts such as anger, possessiveness, or unsound judgement. Whether these actions are minor or major, reflection in a suitable atmosphere can contain our desire to act this way. 
Probably the oldest such reflection on the consequences of anger can be found in Homer's Illiad, which I studied at university. Oddly I have only just noticed that the opening lines of this epic poem start with the observation that the end results of negative emotions are ongoing suffering. Just check out what Homer has to say right at the start of his poem:
Sing, O Muse, of the rage of Achilleus, Peleus’ son, and sing of its devastation that laid a thousandfold pains upon the Achaians; that cost them so many strong-souled heros, sending them down to the dreary House of Death. Sing, O Muse, of how Achilleus' wrath resulted in piles of corpses, once beautiful, strong and vital, now the delicious feast of dogs and birds.
In other words, if we can reflect on the fact that anger does more harm than good, then we begin the process of ending the temporary madness that is anger.
Anger often arises because we overreact to a situation, seeing something in it that really doesn't exist. It's our own perception [better, our misapprehension] of an event, or a person and his or her words or actions (or inaction), that is the real cause of our anger and not the event itself. If, through reflection, we can see that our anger is actually the bigger problem, then we begin to weaken its hold over us. Once we have put aside our anger, we can deal far more effectively with the events that led to our mad counterproductive outburst.
By taking the time to consider whether our actions are better guided by anger or by calm reason, we may find ourselves having fewer angry moments. We could repeatedly ask ourselves what the advantages and disadvantages of anger are.
Yoga philosophy suggests that we should actively cultivate thoughts that oppose negative ones like anger. For instance, kindness and compassion are better for us and others. In fact, deliberating cultivating kindness and compassion has the effect of preventing those around you getting angry.
Writing down in a journal our reflections on anger and how to deal with it can be very helpful. Looking through my own journal has revealed patterns of thought I would not otherwise have noticed. And it has become another teacher because of the numerous reminders of what it means to be angry and how it can be reduced or avoided.
Strategies for reducing anger, and the need for it, should be tailored to the individual and his or her circumstances. Here, a teacher can be of considerable assistance to the seeker.
I suppose what I am trying to convey is the idea that we don't have to live with angry outbursts. We can live happier and more constructive lives without it. We only have to work at it. While I can't say that I am an angry free zone, I do hope that the work I do for myself in this area is bearing fruit.
 q.v. Yogasūtra II.1: "The practice of yoga must reduce both physical and mental impurities. It must develop our capacity for self-examination and help us to understand that, in the final analysis we are not the masters of everything we do". Translated by TKV Desikachar, p. 165 of his book The Heart of Yoga
 Yogasūtra II.34 translated by TKV Desikachar, p. 177 of his book The Heart of Yoga
Photo by Aarón Blanco Tejedor on Unsplash