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5 Mathematical functions

All functions listed here are supported in:

Mathematical functions are supported with float and integer value types, unless stated otherwise.

Some general notes on function parameters:

  • Function parameters are separated by a comma
  • Expressions are accepted as parameters
  • Optional function parameters (or parameter parts) are indicated by < >
FUNCTION
Description Function-specific parameters Comments
abs
The amount of absolute difference between the previous and latest value.

This function references change() to obtain the absolute difference (see example).
Supported value types: float, int, str, text, log

For strings returns:
0 - values are equal
1 - values differ

Example:
=> abs(change(/host/key))>10

Absolute numeric difference will be calculated, as seen with these incoming example values ('previous' and 'latest' value = absolute difference):
'1' and '5' = 4
'3' and '1' = 2
'0' and '-2.5' = 2.5
acos
The arccosine of a value as an angle, expressed in radians. The value must be between -1 and 1.

For example, the arccosine of a value '0.5' will be '2.0943951'.

Example:
=> acos(last(/host/key))
asin
The arcsine of a value as an angle, expressed in radians. The value must be between -1 and 1.

For example, the arcsine of a value '0.5' will be '-0.523598776'.

Example:
=> asin(last(/host/key))
atan
The arctangent of a value as an angle, expressed in radians. For example, the arctangent of a value '1' will be '0.785398163'.

Example:
=> atan(last(/host/key))
atan2 (abscissa)
The arctangent of the ordinate (exprue) and abscissa coordinates specified as an angle, expressed in radians. For example, the arctangent of the ordinate and abscissa coordinates of a value '1' will be '2.21429744'.

Example:
=> atan2(last(/host/key),2)
avg (<value1>,<value2>,...)
Average value of the referenced item values. valueX - value returned by one of history functions Example:
=> avg(avg(/host/key),avg(/host2/key2))
cbrt
Cube root of a value. For example, the cube root of '64' will be '4', of '63' will be '3.97905721'.

Example:
=> cbrt(last(/host/key))
ceil
Round the value up to the nearest greater integer. For example, '2.4' will be rounded up to '3'.

Example:
=> ceil(last(/host/key))

See also floor().
cos
The cosine of a value, where the value is an angle expressed in radians. For example, the cosine of a value '1' will be '0.54030230586'.

Example:
=> cos(last(/host/key))
cosh
The hyperbolic cosine of a value. For example, the hyperbolic cosine of a value '1' will be '1.54308063482'.

Returns value as a real number, not as scientific notation.

Example:
=> cosh(last(/host/key))
cot
The cotangent of a value, where the value is an angle, expressed in radians. For example, the cotangent of a value '1' will be '0.54030230586'.

Example:
=> cot(last(/host/key))
degrees
Converts a value from radians to degrees. For example, a value '1' converted to degrees will be '57.2957795'.

Example:
=> degrees(last(/host/key))
e
Euler's number (2.718281828459045). Example:
=> e()
exp
Euler's number at a power of a value. For example, Euler's number at a power of a value '2' will be '7.38905609893065'.

Example:
=> exp(last(/host/key))
expm1
Euler's number at a power of a value minus 1. For example, Euler's number at a power of a value '2' minus 1 will be '6.38905609893065'.

Example:
=> expm1(last(/host/key))
floor
Round the value down to the nearest smaller integer. For example, '2.6' will be rounded down to '2'.

Example:
=> floor(last(/host/key))

See also ceil().
log
Natural logarithm. For example, the natural logarithm of a value '2' will be '0.69314718055994529'.

Example:
=> log(last(/host/key))
log10
Decimal logarithm. For example, the decimal logarithm of a value '5' will be '0.69897000433'.

Example:
=> log10(last(/host/key))
max (<value1>,<value2>,...)
Highest value of the referenced item values. valueX - value returned by one of history functions Example:
=> max(avg(/host/key),avg(/host2/key2))
min (<value1>,<value2>,...)
Lowest value of the referenced item values. valueX - value returned by one of history functions Example:
=> min(avg(/host/key),avg(/host2/key2))
mod (denominator)
Division remainder. denominator - division denominator For example, division remainder of a value '5' with division denominator '2' will be '1'.

Example:
=> mod(last(/host/key),2)
pi
Pi constant (3.14159265358979). Example:
=> pi()
power (power value)
The power of a value. power value - the Nth power to use For example, the 3rd power of a value '2' will be '8'.

Example:
=> power(last(/host/key),3)
radians
Convert a value from degrees to radians. For example, a value '1' converted to radians will be '0.0174532925'.

Example:
=> radians(last(/host/key))
rand
Return a random integer value. A pseudo-random generated number using time as seed (enough for mathematical purposes, but not cryptography).

Example:
=> rand()
round (decimal places)
Round the value to decimal places. decimal places - specify decimal places for rounding (0 is also possible) For example, a value '2.5482' rounded to 2 decimal places will be '2.55'.

Example:
=> round(last(/host/key),2)
signum
Returns '-1' if a value is negative, '0' if a value is zero, '1' if a value is positive. Example:
=> signum(last(/host/key))
sin
The sine of a value, where the value is an angle expressed in radians. For example, the sine of a value '1' will be '0.8414709848'.

Example:
=> sin(last(/host/key))
sinh
The hyperbolical sine of a value. For example, the hyperbolical sine of a value '1' will be '1.17520119364'.

Example:
=> sinh(last(/host/key))
sqrt
Square root of a value. This function will fail with a negative value.

For example, the square root of a value '3.5' will be '1.87082869339'.

Example:
=> sqrt(last(/host/key))
sum (<value1>,<value2>,...)
Sum of the referenced item values. valueX - value returned by one of history functions Example:
=> sum(avg(/host/key),avg(/host2/key2))
tan
The tangent of a value. For example, the tangent of a value '1' will be '1.55740772465'.

Example:
=> tan(last(/host/key))
truncate (decimal places)
Truncate the value to decimal places. decimal places - specify decimal places for truncating (0 is also possible) Example:
=> truncate(last(/host/key),2)