Enum AutodiffError 

pub enum AutodiffError {
    NonScalarLoss {
        num_elements: usize,
    },
    MissingNode,
    TangentShapeMismatch {
        expected: String,
        got: String,
    },
    HvpNotSupported,
    ModeNotSupported {
        mode: String,
        reason: String,
    },
    InvalidArgument(String),
    GraphFreed,
}

AD-specific error type.

Examples

use chainrules_core::AutodiffError;

let err = AutodiffError::NonScalarLoss { num_elements: 8 };
assert!(format!("{err}").contains("scalar"));

Variants

NonScalarLoss

Loss tensor for pullback must contain exactly one element.

Fields

num_elements: usize

MissingNode

Attempted pullback on a tensor not connected to AD tape.

TangentShapeMismatch

Tangent shape must match primal shape.

Fields

expected: String

Expected shape description.

got: String

Actual shape description.

HvpNotSupported

A ReverseRule does not support HVP (pullback_with_tangents).

ModeNotSupported

The requested AD mode is not supported for the given algebra or operation.

For example, tropical einsum does not support frule (JVP) or hvp — only rrule (VJP) via the argmax route is available.

Examples

use chainrules_core::AutodiffError;

let err = AutodiffError::ModeNotSupported {
    mode: "frule".into(),
    reason: "tropical einsum supports rrule only (max is not smooth)".into(),
};

Fields

mode: String

The unsupported mode (e.g., “frule”, “hvp”).

reason: String

Explanation of why this mode is not supported.

InvalidArgument(String)

Generic AD argument error.

GraphFreed

Attempted to execute backward/grad on a graph that was already freed.

Examples

use chainrules_core::AutodiffError;

let err = AutodiffError::GraphFreed;
assert!(err.to_string().contains("freed"));

Trait Implementations

impl Debug for AutodiffError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for AutodiffError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for AutodiffError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.