Click in-app to access the full platform documentation for your version of DataRobot.

# Building blocks reference¶

This page provides the definitions and usage of all building blocks available to Eureqa models. To access further information about building block configuration, click the Documentation link provided in any Eureqa model blueprint (found in the upper right corner of any building block under the Advanced Tuning tab).

## Arithmetic¶

Building Block Definition Usage
Addition Returns the sum of `x` and `y`. `x+y` or `add(x,y)`
Constant `c` is a real valued constant. `c`
Division Returns the quotient of `x` and `y`. `y` must be non-zero. `x/y` or `div(x,y)`
Input Variable `x` is a variable in your prepared dataset. `x`
Integer Constant `c` is an integer constant. `c`
Multiplication Returns the product of `x` and `y`. `x*y` or `mul(x,y)`
Negation Returns the inverse of `x`. `-x`
Subtraction Returns the difference of `x` and `y`. `x-y` or `sub(x,y)`

## Exponential¶

Building Block Definition Usage
Exponential Returns `e^x`. `exp(x)`
Factorial Returns the product of all positive integers from 1 to `x`. `factorial(x)` or `x!`
Natural Logarithm Returns the natural logarithm (base `e`) of `x`. `log(x)`
Power Returns `x` raised to the power of `y`. `x` and `y` can be any expression. `x^y` or `pow(x,y)`
Square Root Returns the square root of `x`. `x` must be positive. `sqrt(x)`

## Squashing functions¶

Squashing functions take a continuous input variable and map it to a constrained output range.

Recommended use: Depending on the shape of the particular squashing function, that function may be useful in identifying transition points in the data, and/or limiting the total impact of a particular term.

Building Block Definition Usage
Complementary Error Function `1.0 - erf(x)` where `erf(x)` is the integral of the normal distribution. Returns a value between 2 and 0. `erfc(x)`
Error Function Integral of the normal distribution. Returns a value between -1 and +1. `erf(x)`
Gaussian Function Returns `exp(-x^2)`. This is a bell-shaped squashing function. `gauss(x)`
Hyperbolic Tangent The hyperbolic tangent of `x`. Hyperbolic tangent is a common squashing function that returns a value between -1 and +1. `tanh(x)`
Logistic Function Returns `1/(1+exp(-x))`. This is a common sigmoid (s-shaped) squashing function that returns a value between 0 and 1. `logistic(x)`
Step Function Returns 1 if `x` is positive, 0 otherwise. `step(x)`
Sign Returns -1 if `x` is negative, +1 if `x` is positive, and 0 if `x` is zero. `sgn(x)`

## Comparison/Boolean functions¶

Building Block Definition Usage
Equal To Returns 1 if `x` is numerically equal to `y`, 0 otherwise. `equal(x,y)` or `x=y`
Greater Than Returns 1 if `x>y`, 0 otherwise. `greater(x,y)` or `x>y`
Greater Than or Equal To Returns 1 if `x>=y`, 0 otherwise. `greater_or_equal(x,y)` or `x>=y`
If-Then-Else Returns `y` if `x` is greater than 0, `z` otherwise. If `x` is `nan`, the function returns `z`. `if(x,y,z)`
Less Than Returns 1 if `x<y`, 0 otherwise. `less(x,y)` or `x<y`
Less Than or Equal To Returns 1 if `x<=y`, 0 otherwise. `less_or_equal(x,y)` or `x<= y`
Logical And Returns 1 if both `x` and `y` are greater than 0, 0 otherwise. `and(x,y)`
Logical Exclusive Or Returns 1 if `(x<=0 and y>0)` or `(x>0 and y<=0)`, 0 otherwise. `xor(x,y)`
Logical Not Returns 0 if `x` is greater than 0, 1 otherwise. `not( x )`
Logical Or Returns 1 if either `x` or `y` are greater than 0, 0 otherwise. `or(x,y)`

## Trigonometric functions¶

Trigonometric functions are functions of an angle; they relate the angles of a triangle to the length of its sides.

Recommended use: When modeling data from physical systems containing angles as inputs.

Building Block Definition Usage
Cosine The standard trigonometric cosine function. The angle `(x)` is in radians. `cos(x)`
Hyperbolic Cosine The standard trigonometric hyperbolic cosine function. `cosh(x)`
Hyperbolic Sine The standard trigonometric hyperbolic sine function. `sinh(x)`
Sine The standard trigonometric sine function. The angle `(x)` is in radians. `sin(x)`
Tangent The standard trigonometric tangent function. The angle `(x)` is in radians. `tan(x)`

## Inverse trigonometric functions¶

Building Block Definition Usage
Arccosine The standard trigonometric arccosine function. `acos(x)`
Arcsine The standard trigonometric arcsine function. `asin(x)`
Arctangent The standard trigonometric arctangent function. `atan(x)`
Inverse Hyperbolic Cosine The standard inverse hyperbolic cosine function. `acosh(x)`
Inverse Hyperbolic Sine The standard inverse hyperbolic sine function. `asinh(x)`
Inverse Hyperbolic Tangent The standard inverse hyperbolic tangent function. `atanh(x)`
Two-Argument Arctangent The standard trigonometric two-argument arctangent function. `atan2(y,x)`

## Other functions¶

Building Block Definition Usage
Absolute Value Returns the positive value of `x`, without regard for its sign. `abs(x)`
Ceiling Returns the smallest integer not less than `x`. `ceil(x)`
Floor Returns the largest integer not greater than `x`. `floor(x)`
Maximum Returns the maximum (signed) result of `x` and `y`. `max(x,y)`
Minimum Returns the minimum (signed) result of `x` and `y`. `min(x,y)`
Modulo Returns the remainder of `x/y`. `mod(x,y)`
Round Returns an integer of `x` rounded to the nearest integer. `round(x)`

Updated October 26, 2021