ERF and erfc functions

Erf is an error function and c in ERFC is a complementary, so erFC = 1-ERF.
Erf (x) = 2/ SQRT (PI) * Integral from 0 to x of exp(-t^2) DT.
The range is (-1, 1) and the interval length is 2.
Therefore, ERFC is a monotone increasing function, which is often used in the communication principle to calculate the relationship between bit error rate and SNR. The higher the SNR, the lower the bit error rate.

Read More: