Jussi,
Since no one else has gotten back to you on this, I will put in my two cents.
To the best of my knowledge, there is no English word or phrase that is commonly used as an equivalent of the Finnish "suuntakulma". I know that, given an angle, one speaks of the ray eminating from the origin at that angle as a "terminal ray", but I have never heard of anyone wanting to do this the other way around. On the other hand, by way of analogy, I would like to suggest "terminal angle". (Even though the given ray/line might not pass through the origin, a horizontal shift can be applied, and this would not change the angle.)
I think I would have known what you meant by "direction angle" without telling me, so maybe it would be okay to use that.
Warren |
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