Struct MPSMatrixSoftMaxGradient 

pub struct MPSMatrixSoftMaxGradient { /* private fields */ }

Available on crate features MPSCore and MPSKernel and MPSMatrixSoftMax and MPSMatrixTypes only.

Dependencies: This depends on Metal.framework.

Computes the gradient corresponding to a forward MPSMatrixSoftMax object.

A MPSMatrixSoftMaxGradient object computes:

dL_dX_ij = Y_ij * (dL_dY_ij - sum_k(dL_dY_ik * Y_ik)

Where dL_dX is the resulting gradient of the loss function with respect to the original input to the forward MPSMatrixSoftMax operation, Y is the output of the forward MPSMatrixSoftMax operation, and dL_dY is the gradient of the loss function with respect to Y.

See also Apple’s documentation

Implementations

impl MPSMatrixSoftMaxGradient

pub unsafe fn sourceRows(&self) -> NSUInteger

Available on crate feature MPSMatrix only.

The number of rows to consider from the sources in the operation. This property is modifiable and defaults to NSUIntegerMax and the number is adjusted dynamically at kernel encode time (see encodeToCommandBuffer) to fit into the source matrices available starting from [primary/secondary]SourceMatrixOrigin.x, indicating that by default the whole source matrix is used. If a different size is desired then this should be modified prior to encoding the kernel. It is the user’s responsibility to ensure that the resultMatrix parameter in encodeToCommandBuffer is large enough to accommodate the results of this operation, otherwise the results of the encode call are undefined. NOTE: primarySourceMatrixOrigin, secondarySourceMatrixOrigin and resultMatrixOrigin from MPSMatrixBinaryKernel can be used to control the starting points in the primary source, secondary source, and result matrices respectively.

pub unsafe fn setSourceRows(&self, source_rows: NSUInteger)

Available on crate feature MPSMatrix only.

Setter for sourceRows.

pub unsafe fn sourceColumns(&self) -> NSUInteger

Available on crate feature MPSMatrix only.

The number of columns to consider from the sources in the operation. This property is modifiable and defaults to NSUIntegerMax and the number is adjusted dynamically at kernel encode time (see encodeToCommandBuffer) to fit into the source matrices available starting from [primary/secondary]SourceMatrixOrigin.y, indicating that by default the whole source matrix is used. If a different size is desired then this should be modified prior to encoding the kernel. It is the user’s responsibility to ensure that the resultMatrix parameter in encodeToCommandBuffer is large enough to accommodate the results of this operation, otherwise the results of the encode call are undefined. NOTE: primarySourceMatrixOrigin, secondarySourceMatrixOrigin and resultMatrixOrigin from MPSMatrixBinaryKernel can be used to control the starting points in the primary source, secondary source, and result matrices respectively.

pub unsafe fn setSourceColumns(&self, source_columns: NSUInteger)

Available on crate feature MPSMatrix only.

Setter for sourceColumns.

pub unsafe fn initWithDevice( this: Allocated<Self>, device: &ProtocolObject<dyn MTLDevice>, ) -> Retained<Self>

Available on crate feature MPSMatrix only.

Initialize an MPSMatrixSoftMaxGradient object on a device.

Parameter device: The device on which the kernel will execute.

Returns: A valid MPSMatrixSoftMaxGradient object or nil, if failure.

pub unsafe fn encodeToCommandBuffer_gradientMatrix_forwardOutputMatrix_resultMatrix( &self, command_buffer: &ProtocolObject<dyn MTLCommandBuffer>, gradient_matrix: &MPSMatrix, forward_output_matrix: &MPSMatrix, result_matrix: &MPSMatrix, )

Available on crate feature MPSMatrix only.

Encode a MPSMatrixSoftMaxGradient object to a command buffer.

Parameter commandBuffer: A valid MTLCommandBuffer to receive the encoded kernel.

Parameter gradientMatrix: A MPSMatrix object containing gradient values with respect to the forward operation’s output. dL_dY in the class description.

Parameter forwardOutputMatrix: A MPSMatrix object containing the output values from the forward operation. Y in the class description.

Parameter resultMatrix: The MPSMatrix object to hold the resulting gradient values with respect to the forward operation’s input. dL_dX in the class description.

pub unsafe fn initWithCoder_device( this: Allocated<Self>, a_decoder: &NSCoder, device: &ProtocolObject<dyn MTLDevice>, ) -> Option<Retained<Self>>

Available on crate feature MPSMatrix only.

NSSecureCoding compatability

See MPSKernel#initWithCoder. Parameter aDecoder: The NSCoder subclass with your serialized MPSMatrixSoftMaxGradient

Parameter device: The MTLDevice on which to make the MPSMatrixSoftMaxGradient

Returns: A new MPSMatrixSoftMaxGradient object, or nil if failure.

Safety

a_decoder possibly has further requirements.

pub unsafe fn copyWithZone_device( &self, zone: *mut NSZone, device: Option<&ProtocolObject<dyn MTLDevice>>, ) -> Retained<Self>

Available on crate feature MPSMatrix only.

Make a copy of this kernel for a new device -

See: MPSKernel

Parameter zone: The NSZone in which to allocate the object

Parameter device: The device for the new MPSKernel. If nil, then use self.device.

Returns: a pointer to a copy of this MPSKernel. This will fail, returning nil if the device is not supported. Devices must be MTLFeatureSet_iOS_GPUFamily2_v1 or later.

Safety

zone must be a valid pointer or null.

impl MPSMatrixSoftMaxGradient

Methods declared on superclass MPSKernel.

pub unsafe fn initWithCoder( this: Allocated<Self>, a_decoder: &NSCoder, ) -> Option<Retained<Self>>

Available on crate feature MPSMatrix only.

Called by NSCoder to decode MPSKernels

This isn’t the right interface to decode a MPSKernel, but it is the one that NSCoder uses. To enable your NSCoder (e.g. NSKeyedUnarchiver) to set which device to use extend the object to adopt the MPSDeviceProvider protocol. Otherwise, the Metal system default device will be used.

Safety

a_decoder possibly has further requirements.

impl MPSMatrixSoftMaxGradient

Methods declared on superclass NSObject.

pub unsafe fn init(this: Allocated<Self>) -> Retained<Self>

Available on crate feature MPSMatrix only.

pub unsafe fn new() -> Retained<Self>

Available on crate feature MPSMatrix only.

Methods from Deref<Target = MPSMatrixBinaryKernel>

pub unsafe fn primarySourceMatrixOrigin(&self) -> MTLOrigin

Available on crate feature MPSMatrix only.

The origin, relative to [0, 0] in the primary source matrix, at which to start reading values. This property is modifiable and defaults to [0, 0] at initialization time. If a different origin is desired then this should be modified prior to encoding the kernel. The z value must be 0.

pub unsafe fn setPrimarySourceMatrixOrigin( &self, primary_source_matrix_origin: MTLOrigin, )

Available on crate feature MPSMatrix only.

Setter for primarySourceMatrixOrigin.

pub unsafe fn secondarySourceMatrixOrigin(&self) -> MTLOrigin

Available on crate feature MPSMatrix only.

The origin, relative to [0, 0] in the secondary source matrix, at which to start reading values. This property is modifiable and defaults to [0, 0] at initialization time. If a different origin is desired then this should be modified prior to encoding the kernel. The z value must be 0.

pub unsafe fn setSecondarySourceMatrixOrigin( &self, secondary_source_matrix_origin: MTLOrigin, )

Available on crate feature MPSMatrix only.

Setter for secondarySourceMatrixOrigin.

pub unsafe fn resultMatrixOrigin(&self) -> MTLOrigin

Available on crate feature MPSMatrix only.

The origin, relative to [0, 0] in the result matrix, at which to start writing results. This property is modifiable and defaults to [0, 0] at initialization time. If a different origin is desired then this should be modified prior to encoding the kernel. The z value must be 0.

pub unsafe fn setResultMatrixOrigin(&self, result_matrix_origin: MTLOrigin)

Available on crate feature MPSMatrix only.

Setter for resultMatrixOrigin.

pub unsafe fn batchStart(&self) -> NSUInteger

Available on crate feature MPSMatrix only.

The index of the first matrix in the batch. This property is modifiable and defaults to 0 at initialization time. If batch processing should begin at a different matrix this value should be modified prior to encoding the kernel.

pub unsafe fn setBatchStart(&self, batch_start: NSUInteger)

Available on crate feature MPSMatrix only.

Setter for batchStart.

pub unsafe fn batchSize(&self) -> NSUInteger

Available on crate feature MPSMatrix only.

The number of matrices in the batch to process. This property is modifiable and by default allows all matrices available at encoding time to be processed. If a single matrix should be processed set this value to 1.

pub unsafe fn setBatchSize(&self, batch_size: NSUInteger)

Available on crate feature MPSMatrix only.

Setter for batchSize.

Methods from Deref<Target = MPSKernel>

pub unsafe fn options(&self) -> MPSKernelOptions

Available on crate feature MPSCoreTypes only.

The set of options used to run the kernel. subsubsection_options

pub unsafe fn setOptions(&self, options: MPSKernelOptions)

Available on crate feature MPSCoreTypes only.

Setter for options.

pub unsafe fn device(&self) -> Retained<ProtocolObject<dyn MTLDevice>>

The device on which the kernel will be used

pub unsafe fn label(&self) -> Option<Retained<NSString>>

A string to help identify this object.

pub unsafe fn setLabel(&self, label: Option<&NSString>)

Setter for label.

This is copied when set.

pub unsafe fn copyWithZone_device( &self, zone: *mut NSZone, device: Option<&ProtocolObject<dyn MTLDevice>>, ) -> Retained<Self>

Make a copy of this MPSKernel for a new device

-copyWithZone: will call this API to make a copy of the MPSKernel on the same device. This interface may also be called directly to make a copy of the MPSKernel on a new device. Typically, the same MPSKernels should not be used to encode kernels on multiple command buffers from multiple threads. Many MPSKernels have mutable properties that might be changed by the other thread while this one is trying to encode. If you need to use a MPSKernel from multiple threads make a copy of it for each additional thread using -copyWithZone: or -copyWithZone:device:

Parameter zone: The NSZone in which to allocate the object

Parameter device: The device for the new MPSKernel. If nil, then use self.device.

Returns: a pointer to a copy of this MPSKernel. This will fail, returning nil if the device is not supported. Devices must be MTLFeatureSet_iOS_GPUFamily2_v1 or later.

Safety

zone must be a valid pointer or null.

Methods from Deref<Target = NSObject>

pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>

pub fn class(&self) -> &'static AnyClass

Dynamically find the class of this object.

Panics

May panic if the object is invalid (which may be the case for objects returned from unavailable init/new methods).

Example

Check that an instance of NSObject has the precise class NSObject.

use objc2::ClassType;
use objc2::runtime::NSObject;

let obj = NSObject::new();
assert_eq!(obj.class(), NSObject::class());

pub unsafe fn get_ivar<T>(&self, name: &str) -> &T

where T: Encode,

👎Deprecated: this is difficult to use correctly, use Ivar::load instead.

Use Ivar::load instead.

Safety

The object must have an instance variable with the given name, and it must be of type T.

See Ivar::load_ptr for details surrounding this.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: DowncastTarget,

Attempt to downcast the object to a class of type T.

This is the reference-variant. Use Retained::downcast if you want to convert a retained object to another type.

Mutable classes

Some classes have immutable and mutable variants, such as NSString and NSMutableString.

When some Objective-C API signature says it gives you an immutable class, it generally expects you to not mutate that, even though it may technically be mutable “under the hood”.

So using this method to convert a NSString to a NSMutableString, while not unsound, is generally frowned upon unless you created the string yourself, or the API explicitly documents the string to be mutable.

See Apple’s documentation on mutability and on isKindOfClass: for more details.

Generic classes

Objective-C generics are called “lightweight generics”, and that’s because they aren’t exposed in the runtime. This makes it impossible to safely downcast to generic collections, so this is disallowed by this method.

You can, however, safely downcast to generic collections where all the type-parameters are AnyObject.

Panics

This works internally by calling isKindOfClass:. That means that the object must have the instance method of that name, and an exception will be thrown (if CoreFoundation is linked) or the process will abort if that is not the case. In the vast majority of cases, you don’t need to worry about this, since both root objects NSObject and NSProxy implement this method.

Examples

Cast an NSString back and forth from NSObject.

use objc2::rc::Retained;
use objc2_foundation::{NSObject, NSString};

let obj: Retained<NSObject> = NSString::new().into_super();
let string = obj.downcast_ref::<NSString>().unwrap();
// Or with `downcast`, if we do not need the object afterwards
let string = obj.downcast::<NSString>().unwrap();

Try (and fail) to cast an NSObject to an NSString.

use objc2_foundation::{NSObject, NSString};

let obj = NSObject::new();
assert!(obj.downcast_ref::<NSString>().is_none());

Try to cast to an array of strings.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);
// This is invalid and doesn't type check.
let arr = arr.downcast_ref::<NSArray<NSString>>();

This fails to compile, since it would require enumerating over the array to ensure that each element is of the desired type, which is a performance pitfall.

Downcast when processing each element instead.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);

for elem in arr {
    if let Some(data) = elem.downcast_ref::<NSString>() {
        // handle `data`
    }
}

Trait Implementations

impl AsRef<AnyObject> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn as_ref(&self) -> &AnyObject

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<MPSKernel> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn as_ref(&self) -> &MPSKernel

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<MPSMatrixBinaryKernel> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn as_ref(&self) -> &MPSMatrixBinaryKernel

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<MPSMatrixSoftMaxGradient> for MPSMatrixLogSoftMaxGradient

Available on crate feature MPSMatrix only.

fn as_ref(&self) -> &MPSMatrixSoftMaxGradient

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<MPSMatrixSoftMaxGradient> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<NSObject> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn as_ref(&self) -> &NSObject

Converts this type into a shared reference of the (usually inferred) input type.

impl Borrow<AnyObject> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<MPSKernel> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn borrow(&self) -> &MPSKernel

Immutably borrows from an owned value.

impl Borrow<MPSMatrixBinaryKernel> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn borrow(&self) -> &MPSMatrixBinaryKernel

Immutably borrows from an owned value.

impl Borrow<MPSMatrixSoftMaxGradient> for MPSMatrixLogSoftMaxGradient

Available on crate feature MPSMatrix only.

fn borrow(&self) -> &MPSMatrixSoftMaxGradient

Immutably borrows from an owned value.

impl Borrow<NSObject> for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

const NAME: &'static str = "MPSMatrixSoftMaxGradient"

The name of the Objective-C class that this type represents.

type Super = MPSMatrixBinaryKernel

The superclass of this class.

type ThreadKind = <<MPSMatrixSoftMaxGradient as ClassType>::Super as ClassType>::ThreadKind

Whether the type can be used from any thread, or from only the main thread.

fn class() -> &'static AnyClass

Get a reference to the Objective-C class that this type represents.

fn as_super(&self) -> &Self::Super

Get an immutable reference to the superclass.

impl CopyingHelper for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

type Result = MPSMatrixSoftMaxGradient

The immutable counterpart of the type, or Self if the type has no immutable counterpart.

impl Debug for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

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

Formats the value using the given formatter.

impl Deref for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

type Target = MPSMatrixBinaryKernel

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Hash for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Message for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn retain(&self) -> Retained<Self>

where Self: Sized,

Increment the reference count of the receiver.

impl NSCoding for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

unsafe fn encodeWithCoder(&self, coder: &NSCoder)

where Self: Sized + Message,

Safety

unsafe fn initWithCoder( this: Allocated<Self>, coder: &NSCoder, ) -> Option<Retained<Self>>

where Self: Sized + Message,

Safety

impl NSCopying for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn copy(&self) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

unsafe fn copyWithZone(&self, zone: *mut NSZone) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

impl NSObjectProtocol for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn isEqual(&self, other: Option<&AnyObject>) -> bool

where Self: Sized + Message,

Check whether the object is equal to an arbitrary other object.

fn hash(&self) -> usize

where Self: Sized + Message,

An integer that can be used as a table address in a hash table structure.

fn isKindOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of the class, or one of its subclasses.

fn is_kind_of<T>(&self) -> bool

where T: ClassType, Self: Sized + Message,

👎Deprecated: use isKindOfClass directly, or cast your objects with AnyObject::downcast_ref

Check if the object is an instance of the class type, or one of its subclasses.

fn isMemberOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of a specific class, without checking subclasses.

fn respondsToSelector(&self, aSelector: Sel) -> bool

where Self: Sized + Message,

Check whether the object implements or inherits a method with the given selector.

fn conformsToProtocol(&self, aProtocol: &AnyProtocol) -> bool

where Self: Sized + Message,

Check whether the object conforms to a given protocol.

fn description(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object.

fn debugDescription(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object to use when debugging.

fn isProxy(&self) -> bool

where Self: Sized + Message,

Check whether the receiver is a subclass of the NSProxy root class instead of the usual NSObject.

fn retainCount(&self) -> usize

where Self: Sized + Message,

The reference count of the object.

impl NSSecureCoding for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn supportsSecureCoding() -> bool

where Self: Sized + ClassType,

impl PartialEq for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefEncode for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

const ENCODING_REF: Encoding = <MPSMatrixBinaryKernel as ::objc2::RefEncode>::ENCODING_REF

The Objective-C type-encoding for a reference of this type.

impl DowncastTarget for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.

impl Eq for MPSMatrixSoftMaxGradient

Available on crate feature MPSMatrix only.