struct

Symbol

Represents a symbolic value within a Graph.

A Symbol can represent the output of a node, the arguments of a Graph (as seen from within its body), and more generally any symbolic value available within the Graph. Other nodes receive Symbol values as inputs to form a computation graph.

A Symbol may also refer to an existing input or output of a node, and you can change them, such as by swapping a new Symbol.

Conceptually, a Symbol is the equivalent of a variable in Mojo. A Symbol can also be thought of as the end of an edge in the dataflow graph (the other end being one use of that symbol).

Similar to a regular variable, a Symbol has a data type.

Note: All the methods in this type are documented as "Creates foo". This is a shorthand notation for "Adds a node representing an op that returns foo".

Fields

• ​handle (Value): A handle to this Symbol's internal representation.

Implemented traits

AnyType, CollectionElement, Copyable, Movable, Stringable

Methods

__getitem__

__getitem__(self: Self, i: Self, axis: Int = 0) -> Self

Symbolic slicing - indexes a value by a single index.

Uses the mo.slice op.

Args:

• ​i (Self): The index value.
• ​axis (Int): The axis to index at.

Returns:

The slicing result.

__getitem__(self: Self, i: Int, axis: Int = 0) -> Self

Symbolic slicing - indexes a value by a single constant index.

Uses the mo.gather op and automatically wraps i inside a mo.constant.

Args:

• ​i (Int): The index value.
• ​axis (Int): The axis to index at.

Returns:

The slicing result.

__getitem__(self: Self, *s: SymbolicSlice) -> Self

Range-based slicing.

Uses the mo.slice op. Slicing along multiple dimensions is supported.

Args:

• ​*s (SymbolicSlice): The slice values. The ith SymbolicSlice in the variadic list represents the begin:end:step triple for axis i.

Returns:

The slicing result.

__getitem__(self: Self, s: Slice) -> Self

Shorthand for symbolic slicing with an Int range.

This overload only supports slicing along the first axis.

Args:

• ​s (Slice): The slice value.

Returns:

The slicing result.

__neg__

__neg__(self: Self) -> Self

Numerical negative, element-wise.

Returns:

The operation result.

__add__

__add__(self: Self, rhs: Self) -> Self

Element-wise addition.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__add__(self: Self, rhs: Int) -> Self

Element-wise addition by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__add__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise addition by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__sub__

__sub__(self: Self, rhs: Self) -> Self

Element-wise subtraction.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__sub__(self: Self, rhs: Int) -> Self

Element-wise subtraction by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__sub__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise subtraction by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__mul__

__mul__(self: Self, rhs: Self) -> Self

Element-wise multiplication.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__mul__(self: Self, rhs: Int) -> Self

Element-wise multiplication by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__mul__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise multiplication by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__matmul__

__matmul__(self: Self, rhs: Self) -> Self

Matrix multiplication.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__truediv__

__truediv__(self: Self, rhs: Self) -> Self

Element-wise division.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__truediv__(self: Self, rhs: Int) -> Self

Element-wise division by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__truediv__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise division by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__pow__

__pow__(self: Self, rhs: Self) -> Self

Element-wise raise to power.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__pow__(self: Self, rhs: Int) -> Self

Element-wise raise to power by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__pow__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise raise to power by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__radd__

__radd__(self: Self, rhs: Self) -> Self

Element-wise addition.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__radd__(self: Self, rhs: Int) -> Self

Element-wise addition by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__radd__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise addition by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__rsub__

__rsub__(self: Self, rhs: Self) -> Self

Element-wise subtraction.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__rsub__(self: Self, rhs: Int) -> Self

Element-wise subtraction by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__rsub__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise subtraction by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__rmul__

__rmul__(self: Self, rhs: Self) -> Self

Element-wise multiplication.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__rmul__(self: Self, rhs: Int) -> Self

Element-wise multiplication by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__rmul__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise multiplication by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__rtruediv__

__rtruediv__(self: Self, rhs: Self) -> Self

Element-wise division.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__rtruediv__(self: Self, rhs: Int) -> Self

Element-wise division by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__rtruediv__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise division by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

__rpow__

__rpow__(self: Self, rhs: Self) -> Self

Element-wise raise to power.

Args:

• ​rhs (Self): The right hand side operand.

Returns:

The operation result.

__rpow__(self: Self, rhs: Int) -> Self

Element-wise raise to power by an Int literal.

Args:

• ​rhs (Int): The right hand side operand.

Returns:

The operation result.

__rpow__(self: Self, rhs: SIMD[float64, 1]) -> Self

Element-wise raise to power by a Float64.

Args:

• ​rhs (SIMD[float64, 1]): The right hand side operand.

Returns:

The operation result.

graph

graph(self: Self) -> Graph

Returns the Graph owning this Symbol.

Returns:

The parent Graph.

type

type(self: Self) -> Type

Returns this Symbol's type.

Returns:

The Symbol's type.

tensor_type

tensor_type(self: Self) -> TensorType

Returns this Symbol's type, as TensorType.

Implicitly asserts that the type is indeed TensorType, and raises an error otherwise.

Returns:

The tensor type of this Symbol.

rebind

rebind(self: Self, *dims: Dim) -> Self

reshape

reshape(self: Self, *dims: Variant[Symbol, Int]) -> Self

Reshapes this Symbol.

Uses the mo.reshape op. Requires the symbol to be a TensorType.

Args:

• ​*dims (Variant[Symbol, Int]): The new dimensions.

Returns:

A new Symbol that has the given shape.

swapaxes

swapaxes(self: Self, axis1: Int, axis2: Int) -> Self

Interchanges two axes of this Symbol.

Uses the mo.transpose op. Negative values are allowed, and represent the axis number counting from the last.

Args:

• ​axis1 (Int): One of the axes to swap.
• ​axis2 (Int): The other axis.

Returns:

A new transposed Symbol.

print

print(self: Self, label: String = "debug_tensor")

Prints this Symbol's value at runtime.

This uses mo.debug.tensor.print to enable printing the runtime value that this Symbol represents, at grpah execution time.

Args:

• ​label (String): A label to accompany the printout.

insert_transformation

insert_transformation(self: Self, transform: fn(Symbol) raises -> Symbol)

Inserts nodes in between this Symbol and all its current uses.

This enables inserting ops in between this Symbol and all its uses, for example to modify an existing Graph.

Note: The function is called exactly once, even if self has no uses.

Args:

• ​transform (fn(Symbol) raises -> Symbol): A function that creates a unary subgraph (single input, single output) and returns the result of the final node. The function will be called with this Symbol, and its return value will replace all of its uses.