water.rapids.ast.prims.operators

Class AstBinOp

java.lang.Object

water.Iced<T>

water.rapids.ast.AstRoot<T>

water.rapids.ast.AstPrimitive

water.rapids.ast.prims.operators.AstBinOp

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Cloneable, Freezable

Direct Known Subclasses:

AstAnd, AstDiv, AstEq, AstGe, AstGt, AstIntDiv, AstIntDivR, AstLAnd, AstLe, AstLOr, AstLt, AstMod, AstModR, AstMul, AstNe, AstOr, AstPlus, AstPow, AstRound, AstSignif, AstSub

public abstract class AstBinOp
extends AstPrimitive

Binary operator. Subclasses auto-widen between scalars and Frames, and have exactly two arguments

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AstBinOp()

Method Summary

Modifier and Type	Method and Description
Val	apply(Env env, Env.StackHelp stk, AstRoot[] asts) Primary method to invoke this function, passing all the parameters as the `asts` list.
java.lang.String[]	args() List of argument names.
boolean	categoricalOK() Does it make sense to run this operation on a categorical variable ?
ValFrame	frame_op_scalar(Frame fr, double d) Auto-widen the scalar to every element of the frame
int	nargs() Number of function's arguments + 1.
abstract double	op(double l, double r) Override to express a basic math primitive
Val	prim_apply(Val left, Val rite)
double	str_op(BufferedString l, BufferedString r)

Methods inherited from class water.rapids.ast.AstPrimitive

description, example, exec

Methods inherited from class water.rapids.ast.AstRoot

str, toString

Methods inherited from class water.Iced

asBytes, clone, copyOver, frozenType, read, readExternal, readJSON, reloadFromBytes, toJsonBytes, toJsonString, write, writeExternal, writeJSON

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AstBinOp

public AstBinOp()

Method Detail

args

public java.lang.String[] args()

Description copied from class: AstPrimitive

List of argument names. The length of the returned array should be equal to `nargs() - 1` (unless `nargs()` returns -1, in which case this function may return {"..."} or something similar).

Specified by:

args in class AstPrimitive

nargs

public int nargs()

Description copied from class: AstPrimitive

Number of function's arguments + 1. Thus, a binary operator like '+' should be declared with 3 nargs: ["+", lhs, rhs]. For variable-argument functions this method should return -1.

Specified by:

nargs in class AstPrimitive

apply

public Val apply(Env env,
                 Env.StackHelp stk,
                 AstRoot[] asts)

Description copied from class: AstPrimitive

Primary method to invoke this function, passing all the parameters as the `asts` list.

Specified by:

apply in class AstPrimitive

Parameters:

env - Current execution environment. Variables are looked up here.

stk - TODO need clarification

asts - List of AstRoot expressions that are arguments to the function. First element in this list is the function itself.

Returns:

value resulting from calling the function with the provided list of arguments.

prim_apply

public Val prim_apply(Val left,
                      Val rite)

op

public abstract double op(double l,
                          double r)

Override to express a basic math primitive

str_op

public double str_op(BufferedString l,
                     BufferedString r)

frame_op_scalar

public ValFrame frame_op_scalar(Frame fr,
                                double d)

Auto-widen the scalar to every element of the frame

categoricalOK

public boolean categoricalOK()

Does it make sense to run this operation on a categorical variable ?

Returns:

True if the operation may be applied on a categorical variable, otherwise false.