EMA is not a true EMA

[jaspreetssethi]

It seems the ema indicator is not a true ema but rather a WMA implementation.
By definition ema should require one more observation than the window size as first observation is an SMA.
Seems this is not the case in the current implementation.

see https://www.investopedia.com/ask/answers/071414/whats-difference-between-moving-average-and-weighted-moving-average.asp