For statistical analysis of collected/polled Zabbix data some formulas needs to be used.
Variance needs ability to add to power of 2. (X ** 2 or X^2)
Standard deviation needs square root (of variance). ( SQRT(X) or X**0.5 or X^0.5)
Perhaps some others might need to have LN, LOG, EXP etc.
Example use case:
Cisco routers provide SLA monitoring and SNMP MIB returns NumberOfMeasures, SumOfMeasures and SumOfMeasuresSquared. From these 3 variables I can calculate
- average RTT
- variance of RTT
- standard deviation of RTT
Unfortunately only last (standard deviation) needs to be calculated with external program as according to manual Zabbix does not support SQRT-function.
Also power could be used to combine two 32-bit counters to one 64-bit: counter + counterHigh*2^32 instead of counter + counterHigh*4294967296..
Luckily PHP has SQRT() and POW() for web interface based square rooting and powering. C++ math.h also has it. So it should not be that big thing or?