My personal opinion - showing anger at work is a mistake. Most people know that. The question is really how to deal with anger without letting it show and without letting it eat you alive.
The issue is particularly heightened for women I think. Showing anger undermines your credibility because it makes you look irrational. Even if you are right.
There are a lot of things you can do to handle anger productively. In the short term, talk to a family member or friend. Go for a walk outside. Listen to music. When you have simmered down, reflect. Figure out a way to deal with the problem minus emotion.
Often yiu misunderstand rhe other person's intentions or motivations.
Also read any book by the Dalai Lama. You really can have compassion on the person or situation that made you angry. You can know that anger hurts you more than them. That anger comes from your own ego. That you make yourself angry - the situation does not control you. Etc.
BTW - never write an email when you are mad. We all know that, but just saying.