5 Mathematical functions

All functions listed here are supported in:

• Trigger expressions
• Calculated items

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 details

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 < >

abs(value)

The absolute value of a value.
Supported value types: Float, Integer, String, Text, Log.
For strings returns: 0 - the values are equal; 1 - the values differ.

Parameter:

• value - the value to check

The 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

Example:

abs(last(/host/key))>10

acos(value)

The arccosine of a value as an angle, expressed in radians.

Parameter:

• value - the value to check

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(value)

The arcsine of a value as an angle, expressed in radians.

Parameter:

• value - the value to check

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(value)

The arctangent of a value as an angle, expressed in radians.

Parameter:

• value - the value to check

The value must be between -1 and 1. For example, the arctangent of a value '1' will be '0.785398163'.

Example:

atan(last(/host/key))

atan2(value,abscissa)

The arctangent of the ordinate (exprue) and abscissa coordinates specified as an angle, expressed in radians.

Parameter:

• value - the value to check;
• abscissa - the abscissa value.

For example, the arctangent of the ordinate and abscissa coordinates of a value '1' will be '2.21429744'.

Example:

atan(last(/host/key),2)

avg(<value1>,<value2>,...)

The average value of the referenced item values.

Parameter:

• valueX - the value returned by one of the history functions.

Example:

avg(avg(/host/key),avg(/host2/key2))

cbrt(value)

The cube root of a value.

Parameter:

• value - the value to check

For example, the cube root of '64' will be '4', of '63' will be '3.97905721'.

Example:

cbrt(last(/host/key))

ceil(value)

Round the value up to the nearest greater or equal integer.

Parameter:

• value - the value to check

For example, '2.4' will be rounded up to '3'. See also floor().

Example:

ceil(last(/host/key))

cos(value)

The cosine of a value, where the value is an angle expressed in radians.

Parameter:

• value - the value to check

For example, the cosine of a value '1' will be '0.54030230586'.

Example:

cos(last(/host/key))

cosh(value)

The hyperbolic cosine of a value. Returns the value as a real number, not as scientific notation.

Parameter:

• value - the value to check

For example, the hyperbolic cosine of a value '1' will be '1.54308063482'.

Example:

cosh(last(/host/key))

cot(value)

The cotangent of a value, where the value is an angle expressed in radians.

Parameter:

• value - the value to check

For example, the cotangent of a value '1' will be '0.54030230586'.

Example:

cot(last(/host/key))

degrees(value)

Converts a value from radians to degrees.

Parameter:

• value - the value to check

For example, a value '1' converted to degrees will be '57.2957795'.

Example:

degrees(last(/host/key))

e

The Euler's number (2.718281828459045).

Example:

e()

exp(value)

The Euler's number at a power of a value.

Parameter:

• value - the value to check

For example, Euler's number at a power of a value '2' will be '7.38905609893065'.

Example:

exp(last(/host/key))

expm1(value)

The Euler's number at a power of a value minus 1.

Parameter:

• value - the value to check

For example, Euler's number at a power of a value '2' minus 1 will be '6.38905609893065'.

Example:

expm1(last(/host/key))

floor(value)

Round the value down to the nearest smaller or equal integer.

Parameter:

• value - the value to check

For example, '2.6' will be rounded down to '2'. See also ceil().

Example:

floor(last(/host/key))

log(value)

The natural logarithm.

Parameter:

• value - the value to check

For example, the natural logarithm of a value '2' will be '0.69314718055994529'.

Example:

log(last(/host/key))

log10(value)

The decimal logarithm.

Parameter:

• value - the value to check

For example, the decimal logarithm of a value '5' will be '0.69897000433'.

Example:

log10(last(/host/key))

max(<value1>,<value2>,...)

The highest value of the referenced item values.

Parameter:

• valueX - the value returned by one of the history functions.

Example:

max(avg(/host/key),avg(/host2/key2))

min(<value1>,<value2>,...)

The lowest value of the referenced item values.

Parameter:

• valueX - the value returned by one of the history functions.

Example:

min(avg(/host/key),avg(/host2/key2))

mod(value,denominator)

The division remainder.

Parameter:

• value - the value to check;
• denominator - the division denominator.

For example, division remainder of a value '5' with division denominator '2' will be '1'.

Example:

mod(last(/host/key),2)

pi

The Pi constant (3.14159265358979).

Example:

pi()

power(value,power value)

The power of a value.

Parameter:

• value - the value to check;
• 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(value)

Converts a value from degrees to radians.

Parameter:

• value - the value to check

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(value,decimal places)

Round the value to decimal places.

Parameter:

• value - the value to check;
• 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(value)

Returns '-1' if a value is negative, '0' if a value is zero, '1' if a value is positive.

Parameter:

• value - the value to check.

For example, a value '2.5482' rounded to 2 decimal places will be '2.55'.

Example:

signum(last(/host/key))

sin(value)

The sine of a value, where the value is an angle expressed in radians.

Parameter:

• value - the value to check

For example, the sine of a value '1' will be '0.8414709848'.

Example:

sin(last(/host/key))

sinh(value)

The hyperbolical sine of a value, where the value is an angle expressed in radians.

Parameter:

• value - the value to check

For example, the hyperbolical sine of a value '1' will be '1.17520119364'.

Example:

sinh(last(/host/key))

sqrt(value)

The square root of a value.
This function will fail with a negative value.

Parameter:

• value - the value to check

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

Example:

sqrt(last(/host/key))

sum(<value1>,<value2>,...)

The sum of the referenced item values.

Parameter:

• valueX - the value returned by one of the history functions.

Example:

sum(avg(/host/key),avg(/host2/key2))

tan(value)

The tangent of a value.

Parameter:

• value - the value to check

For example, the tangent of a value '1' will be '1.55740772465'.

Example:

tan(last(/host/key))

truncate(value,decimal places)

Truncate the value to decimal places.

Parameter:

• value - the value to check;
• decimal places - specify decimal places for truncating (0 is also possible).

For example, a value '2.5482' truncated to 2 decimal places will be '2.54'.

Example:

truncate(last(/host/key),2)

Vedi tutte le funzioni supportate.