[Closed] Acos return #ind

I know somebody says something about bit.isNan when #ind occurs but I really dind’t find a solution for that.

I have two lines in 2d(top view, no z needed) and I’m trying to retrieve an angle between those.

So the question is: how can I obtain the degrees between the two splines without #ind errors?

Acos, as the docs suggest, would return a float. Does that represent the angle? eg. 45.0= 45 degrees?

first_line = selection[1]
second_line = selection[2]

a = getKnotpoint first_line 1 1
b = getKnotpoint first_line 1 2

first_vector = b-a

print first_vector

c = getKnotpoint second_line 1 1
d = getKnotpoint second_line 1 2

second_vector = d-c

print second_vector


nv1 = normalize first_vector
nv2 = normalize second_vector

format "nv1 is %" nv1
format "nv2 is %" nv2

dotProduct = nv1.x*nv2.x + nv1.y*nv2.y

format "dotProduct is %" dotProduct

result = acos dotProduct

format "final resukt is %" result

As you can see, debugging with format led me to isolate the problem on the last operation(acos doProduct). I know I could have used prewritten function like dot but I need it for learning purposes.