iSedDev() different values from stddev.mq5 on charts for EMA methods

 

hi guys, can anyone help me figure out whats going on?

loading stddev indicator on the chart in these 2 ways:
1) is equivalent to calling STDDEVhandle = iStdDev(NULL,0,STDperiod,0,STDmethod,STDprice); (Standard Deviation from Navigator/Trend Indicator)
2) loading the stddev.mq5 compiled indicator of code taken from this codebase page https://www.mql5.com/en/code/49 (official MetaQuotes page code)

the results are the same for any period and prices applied with methods type SMA, SMMA and LWMA
unfortunately with method EMA values generated are different at start bars, why?

image attached, try yourself to verify

Standard Deviation (StdDev)
Standard Deviation (StdDev)
  • www.mql5.com
The Standard Deviation (StdDev) measures the market volatility. This indicator charactrizes the scale of price changes relating to the Moving Average.
Files: