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v0.3.11 Latest Latest
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 Go to latest Published: Jan 1, 2025 License: BSD-3-Clause Imports: 19 Imported by: 18

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Constants

This section is empty.

Variables

View Source 
var BinaryOps = make(map[string]BinaryOp)
View Source 
var IvyEval func(context Context, s string) Value

Implemented in package run, handled as a func to avoid a dependency loop.

View Source 
var (
	MaxBigInt63 = big.NewInt(int64(^uint64(0) >> 1)) // Used in ../parse/special.go

)
View Source 
var UnaryOps = make(map[string]UnaryOp)

Functions

func Assign added in v0.3.8 

func Assign(context Context, left, right Expr, rhs Value)

func Errorf 

func Errorf(format string, args ...interface{})

Errorf panics with the formatted string, with type Error.

func IndexAssign added in v0.1.12 

func IndexAssign(context Context, top, left Expr, index []Expr, right Expr, rhs Value)

IndexAssign handles general assignment to indexed expressions on the LHS. Left and index will be evaluated (right to left), while top is only for its ProgString method. The caller must check that left is a variable expression, so that the assignment is not being written into a temporary.

func IsCompound added in v0.3.8 

func IsCompound(x interface{}) bool

IsCompound reports whether the item is a non-trivial expression tree, one that may require parentheses around it when printed to maintain correct evaluation order.

func IsScalarType added in v0.3.0 

func IsScalarType(v Value) bool

IsScalarType reports whether u is an actual scalar, an int or float etc.

func MaxParallelismForTesting added in v0.1.12 

func MaxParallelismForTesting()

func OrderedCompare added in v0.3.0 

func OrderedCompare(c Context, u, v Value) int

OrderedCompare returns -1, 0, or 1 according to whether u is less than, equal to, or greater than v, according to total ordering rules. Total ordering is not the usual mathematical definition, as we honor things like 1.0 == 1, comparison of int and char is forbidden, and complex numbers do not implement <. Plus other than for scalars we don't need to follow any particular rules at all, just what works for sorting sets.

Thus we amend the usual orderings: - Char is below all other types - All other scalars are compared directly, except... - ...Complex is above all other scalars, unless on the real line: 1j0 == 1. - Vector is above all other types except... - ...Matrix, which is above all other types.

When comparing identically-typed values:

  • Complex is ordered first by real component, then by imaginary.
  • Vector and Matrix are ordered first by number of elements, then in lexical order of elements.

These are unusual rules, but they are provide a unique ordering of elements sufficient for set membership. // Exported for testing, which is done by the parent directory to avoid a dependency cycle.

func ParseString 

func ParseString(s string) string

ParseString parses a string. Single quotes and double quotes are both allowed (but must be consistent.) The result must contain only valid Unicode code points.

func TraceBinary added in v0.3.10 

func TraceBinary(c Context, level int, u Value, op string, v Value)

TraceBinary prints a trace line for a binary operator.

func TraceUnary added in v0.3.10 

func TraceUnary(c Context, level int, op string, v Value)

TraceUnary prints a trace line for a unary operator.

Types

type Assignment added in v0.3.8 

type Assignment struct {
	Value
}

Assignment is an implementation of Value that is created as the result of an assignment. It can be type-asserted to discover whether the returned value was created by assignment, such as is done in the interpreter to avoid printing the results of assignment expressions.

type BigFloat 

type BigFloat struct {
	*big.Float
}

func Consts 

func Consts(c Context) (e, pi BigFloat)

func (BigFloat) Copy added in v0.3.0 

func (f BigFloat) Copy() Value

func (BigFloat) Eval 

func (f BigFloat) Eval(Context) Value

func (BigFloat) Format 

func (f BigFloat) Format()

The fmt package looks for Formatter before Stringer, but we want to use Stringer only. big.Float implements Formatter, and we embed it in our BigFloat type. To make sure that our String gets called rather than the inner Format, we put a non-matching stub Format method into this interface. This is ugly but very simple and cheap.

func (BigFloat) Inner 

func (f BigFloat) Inner() Value

func (BigFloat) ProgString 

func (f BigFloat) ProgString() string

func (BigFloat) Rank 

func (f BigFloat) Rank() int

func (BigFloat) Sprint 

func (f BigFloat) Sprint(conf *config.Config) string

func (BigFloat) String 

func (f BigFloat) String() string

type BigInt 

type BigInt struct {
	*big.Int
}

func (BigInt) BitLen 

func (i BigInt) BitLen() int64

func (BigInt) Copy added in v0.3.0 

func (i BigInt) Copy() Value

func (BigInt) Eval 

func (i BigInt) Eval(Context) Value

func (BigInt) Format 

func (i BigInt) Format()

The fmt package looks for Formatter before Stringer, but we want to use Stringer only. big.Int and big.Rat implement Formatter, and we embed them in our BigInt and BigRat types. To make sure that our String gets called rather than the inner Format, we put a non-matching stub Format method into this interface. This is ugly but very simple and cheap.

func (BigInt) Inner 

func (i BigInt) Inner() Value

func (BigInt) ProgString 

func (i BigInt) ProgString() string

func (BigInt) Rank 

func (i BigInt) Rank() int

func (BigInt) Sprint 

func (i BigInt) Sprint(conf *config.Config) string

func (BigInt) String 

func (i BigInt) String() string

type BigRat 

type BigRat struct {
	*big.Rat
}

func (BigRat) Copy added in v0.3.0 

func (r BigRat) Copy() Value

func (BigRat) Eval 

func (r BigRat) Eval(Context) Value

func (BigRat) Inner 

func (r BigRat) Inner() Value

func (BigRat) ProgString 

func (r BigRat) ProgString() string

func (BigRat) Rank 

func (r BigRat) Rank() int

func (BigRat) Sprint 

func (r BigRat) Sprint(conf *config.Config) string

func (BigRat) String 

func (r BigRat) String() string

type BinaryExpr added in v0.3.8 

type BinaryExpr struct {
	Op    string
	Left  Expr
	Right Expr
}

func (*BinaryExpr) Eval added in v0.3.8 

func (b *BinaryExpr) Eval(context Context) Value

func (*BinaryExpr) ProgString added in v0.3.8 

func (b *BinaryExpr) ProgString() string

type BinaryOp 

type BinaryOp interface {
	EvalBinary(c Context, right, left Value) Value
}

BinaryOp is the interface implemented by a simple binary operator.

type Char 

type Char rune

func (Char) Copy added in v0.3.0 

func (c Char) Copy() Value

func (Char) Eval 

func (c Char) Eval(Context) Value

func (Char) Inner 

func (c Char) Inner() Value

func (Char) ProgString 

func (c Char) ProgString() string

func (Char) Rank 

func (c Char) Rank() int

func (Char) Sprint 

func (c Char) Sprint(conf *config.Config) string

func (Char) String 

func (c Char) String() string

type Complex added in v0.2.0 

type Complex struct {
	// contains filtered or unexported fields
}

func NewComplex added in v0.3.0 

func NewComplex(u, v Value) Complex

func (Complex) Components added in v0.2.0 

func (c Complex) Components() (Value, Value)

func (Complex) Copy added in v0.3.0 

func (c Complex) Copy() Value

func (Complex) Eval added in v0.2.0 

func (c Complex) Eval(Context) Value

func (Complex) Inner added in v0.2.0 

func (c Complex) Inner() Value

func (Complex) ProgString added in v0.2.0 

func (c Complex) ProgString() string

func (Complex) Rank added in v0.2.0 

func (c Complex) Rank() int

func (Complex) Signum added in v0.3.1 

func (c Complex) Signum(ctx Context) Complex

Signum returns: 

0j0      if c == 0
c/abs c  if c != 0

func (Complex) Sprint added in v0.2.0 

func (c Complex) Sprint(conf *config.Config) string

func (Complex) String added in v0.2.0 

func (c Complex) String() string

type CondExpr added in v0.3.8 

type CondExpr struct {
	Cond *BinaryExpr
}

CondExpr is a CondExpr executor: expression ":" expression

func (*CondExpr) Eval added in v0.3.8 

func (c *CondExpr) Eval(context Context) Value

func (*CondExpr) Operands added in v0.3.8 

func (c *CondExpr) Operands() (left, right Expr)

func (*CondExpr) Operator added in v0.3.8 

func (c *CondExpr) Operator() string

func (*CondExpr) ProgString added in v0.3.8 

func (c *CondExpr) ProgString() string

type Context 

type Context interface {
	// Config returns the configuration state for evaluation.
	Config() *config.Config

	// Local returns the value of the i'th local variable.
	Local(i int) Value

	// AssignLocal assigns to the i'th local variable.
	AssignLocal(i int, value Value)

	// Global returns the value of the named global variable.
	Global(name string) Value

	// AssignGlobal assigns to the named global variable.
	AssignGlobal(name string, value Value)

	// Eval evaluates a list of expressions.
	Eval(exprs []Expr) []Value

	// EvalUnary evaluates a unary operator.
	EvalUnary(op string, right Value) Value

	// EvalBinary evaluates a binary operator.
	EvalBinary(left Value, op string, right Value) Value

	// UserDefined reports whether the specified op is user-defined.
	UserDefined(op string, isBinary bool) bool

	// TraceIndent returns an indentation marker showing the depth of the stack.
	TraceIndent() string
}

Context is the execution context for evaluation. The only implementation is ../exec/Context, but the interface is defined separately, here, because of the dependence on Expr and the import cycle that would otherwise result.

type Decomposable added in v0.1.1 

type Decomposable interface {
	// Operator returns the operator, or "" for a singleton.
	Operator() string

	// Operands returns the left and right operands, or nil if absent.
	// For singletons, both will be nil, but ProgString can
	// give the underlying name or value.
	Operands() (left, right Expr)
}

Decomposable allows one to pull apart a parsed expression. Only implemented by Expr types that need to be decomposed in function evaluation.

type Error 

type Error string

Error is the type we recognize as a recoverable run-time error.

func (Error) Error 

func (err Error) Error() string

type Expr 

type Expr interface {
	// ProgString returns the unambiguous representation of the
	// expression to be used in program source.
	ProgString() string

	Eval(Context) Value
}

Expr is the interface for a parsed expression. Also implemented by Value.

type IndexExpr added in v0.3.8 

type IndexExpr struct {
	Op    string
	Left  Expr
	Right []Expr
}

func (*IndexExpr) Eval added in v0.3.8 

func (x *IndexExpr) Eval(context Context) Value

func (*IndexExpr) ProgString added in v0.3.8 

func (x *IndexExpr) ProgString() string

type Int 

type Int int64

func (Int) Copy added in v0.3.0 

func (i Int) Copy() Value

func (Int) Eval 

func (i Int) Eval(Context) Value

func (Int) Inner 

func (i Int) Inner() Value

func (Int) ProgString 

func (i Int) ProgString() string

func (Int) Rank 

func (i Int) Rank() int

func (Int) Sprint 

func (i Int) Sprint(conf *config.Config) string

func (Int) String 

func (i Int) String() string

func (Int) ToBool 

func (i Int) ToBool() bool

type Matrix 

type Matrix struct {
	// contains filtered or unexported fields
}

func NewMatrix 

func NewMatrix(shape []int, data *Vector) *Matrix

NewMatrix makes a new matrix. The number of elements must fit in an Int.

func (*Matrix) Copy 

func (m *Matrix) Copy() Value

func (*Matrix) Data 

func (m *Matrix) Data() *Vector

Data returns the data of the matrix as a vector.

func (*Matrix) ElemSize 

func (m *Matrix) ElemSize() int

ElemSize returns the size of each top-level element of the matrix. Given shape [a, b, c, ...] it is b*c*....

func (*Matrix) Eval 

func (m *Matrix) Eval(Context) Value

func (*Matrix) Inner 

func (m *Matrix) Inner() Value

func (*Matrix) ProgString 

func (m *Matrix) ProgString() string

func (*Matrix) Rank 

func (m *Matrix) Rank() int

func (*Matrix) Shape 

func (m *Matrix) Shape() []int

Shape returns the shape of the matrix.

func (*Matrix) Size 

func (m *Matrix) Size() int

Size returns number of elements of the matrix. Given shape [a, b, c, ...] it is a*b*c*....

func (*Matrix) Sprint 

func (m *Matrix) Sprint(conf *config.Config) string

func (*Matrix) String 

func (m *Matrix) String() string

type UnaryExpr added in v0.3.8 

type UnaryExpr struct {
	Op    string
	Right Expr
}

func (*UnaryExpr) Eval added in v0.3.8 

func (u *UnaryExpr) Eval(context Context) Value

func (*UnaryExpr) ProgString added in v0.3.8 

func (u *UnaryExpr) ProgString() string

type UnaryOp 

type UnaryOp interface {
	EvalUnary(c Context, right Value) Value
}

UnaryOp is the interface implemented by a simple unary operator.

type Value 

type Value interface {
	// String is for internal debugging only. It uses default configuration
	// and puts parentheses around every value so it's clear when it is used.
	// All user output should call Sprint instead.
	String() string
	Sprint(*config.Config) string

	// Eval evaluates (simplifies) the Value.
	Eval(Context) Value

	// Copy returns a copy of the Value.
	Copy() Value

	// Inner retrieves the value, without evaluation. But for Assignments,
	// it returns the right-hand side.
	Inner() Value

	// Rank returns the rank of the value: 0 for scalar, 1 for vector, etc.
	Rank() int

	// ProgString is like String, but suitable for program listing.
	// For instance, it ignores the user format for numbers and
	// puts quotes on chars, guaranteeing a correct representation.
	ProgString() string
	// contains filtered or unexported methods
}

func BinaryEach added in v0.3.7 

func BinaryEach(c Context, lv Value, op string, rv Value) Value

BinaryEach computes the result of applying op to lv and rv, applying the "each" expansion depending on how many times @ appears on the left and right ends of op.

func Each added in v0.3.7 

func Each(c Context, op string, v Value) Value

Each computes the result of running op on each element of v. The trailing @ has been removed.

func EvalCharEqual added in v0.3.0 

func EvalCharEqual(u Value, isEqualOp bool, v Value) (Value, bool)

EvalCharEqual handles == and != in a special case: If comparing a scalar against a Char, avoid the conversion. The logic of type promotion in EvalBinary otherwise interferes with comparison because it tries to force scalar types to be the same, and char doesn't convert to any other type.

func EvalFunctionBody added in v0.1.1 

func EvalFunctionBody(context Context, fnName string, body []Expr) Value

EvalFunctionBody evaluates the list of expressions inside a function, possibly with conditionals that generate an early return.

func Index added in v0.1.12 

func Index(context Context, top, left Expr, index []Expr) Value

Index returns left[index]. Left and index will be evaluated (right to left), while top is only for its ProgString method.

func Parse 

func Parse(conf *config.Config, s string) (Value, error)

func Product 

func Product(c Context, u Value, op string, v Value) Value

Product computes a compound product, such as an inner product "+.*" or outer product "o.*". The op is known to contain a period. The operands are all at least vectors, and for inner product they must both be vectors.

func QuoRem added in v0.3.0 

func QuoRem(op string, c Context, a, b Value) (div, rem Value)

QuoRem uses Euclidean division to return the quotient and remainder for a/b. The quotient will be an integer, possibly negative; the remainder is always positive and may be fractional. Returned values satisfy the identity that 

quo = a div b  such that
rem = a - b*quo  with 0 <= rem < |y|

See comment for math/big.Int.DivMod for details. Exported for testing.

func Reduce 

func Reduce(c Context, op string, v Value) Value

Reduce computes a reduction such as +/. The slash has been removed.

func ReduceFirst added in v0.3.0 

func ReduceFirst(c Context, op string, v Value) Value

ReduceFirst computes a reduction such as +/% along the first axis. The slash-percent has been removed.

func Scan 

func Scan(c Context, op string, v Value) Value

Scan computes a scan of the op; the \ has been removed. It gives the successive values of reducing op through v. We must be right associative; that is the grammar.

func ScanFirst added in v0.3.0 

func ScanFirst(c Context, op string, v Value) Value

ScanFirst computes a scan of the op along the first axis. The backslash-percent has been removed. It gives the successive values of reducing op through v. We must be right associative; that is the grammar.

type VarExpr added in v0.3.8 

type VarExpr struct {
	Name  string
	Local int // local index, or 0 for global
}

VarExpr identifies a variable to be looked up and evaluated.

func NewVar added in v0.3.8 

func NewVar(name string) *VarExpr

func (*VarExpr) Eval added in v0.3.8 

func (e *VarExpr) Eval(context Context) Value

func (*VarExpr) ProgString added in v0.3.8 

func (e *VarExpr) ProgString() string

type Vector 

type Vector struct {
	// contains filtered or unexported fields
}

func NewIntVector 

func NewIntVector(elems ...int) *Vector

func NewVector 

func NewVector(elems []Value) *Vector

func (*Vector) All added in v0.3.8 

func (v *Vector) All() []Value

All returns all the elements in v, for reading.

func (*Vector) AllChars 

func (v *Vector) AllChars() bool

AllChars reports whether the vector contains only Chars.

func (*Vector) AllInts added in v0.1.6 

func (v *Vector) AllInts() bool

AllInts reports whether the vector contains only Ints.

func (*Vector) At added in v0.3.8 

func (v *Vector) At(i int) Value

At returns the i'th element of v.

func (*Vector) Copy 

func (v *Vector) Copy() Value

func (*Vector) Eval 

func (v *Vector) Eval(Context) Value

func (*Vector) Inner 

func (v *Vector) Inner() Value

func (*Vector) Len added in v0.3.8 

func (v *Vector) Len() int

Len returns the number of elements in v.

func (*Vector) ProgString 

func (v *Vector) ProgString() string

func (*Vector) Rank 

func (v *Vector) Rank() int

func (*Vector) Set added in v0.3.8 

func (v *Vector) Set(i int, x Value)

Set sets v[i] = x.

func (*Vector) Slice added in v0.3.8 

func (v *Vector) Slice(i, j int) []Value

Slice returns a slice v[i:j], for reading.

func (*Vector) Sprint 

func (v *Vector) Sprint(conf *config.Config) string

func (*Vector) String 

func (v *Vector) String() string

func (*Vector) Writable added in v0.3.8 

func (v *Vector) Writable() []Value

Writable returns all the elements in v, for writing.

type VectorExpr added in v0.3.8 

type VectorExpr []Expr

VectorExpr holds a syntactic vector to be verified and evaluated.

func (VectorExpr) Eval added in v0.3.8 

func (e VectorExpr) Eval(context Context) Value

func (VectorExpr) ProgString added in v0.3.8 

func (e VectorExpr) ProgString() string

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