Tensor
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#include "modular/c/tensor.h"
Functions

M_TensorSpec *M_newTensorSpec(const int64_t *shape, size_t rankSize, M_Dtype dtype, const char *tensorName)¶
Creates a tensor specification.
You need this before you set the input tensors with
M_borrowTensorInto()
.When storing tensor data in memory, we always use a diminishing stride size. That is, earlier dimensions in the shape have larger strides than later dimensions. For example, a C array declared as
int arr[1][2][3]
would have a shape specified as{1, 2, 3}
. Parameters:
shape – The shape of the tensor.
rankSize – The rank size of the tensor.
dtype – The datatype for the tensor.
tensorName – The name for the tensor. This string gets copied as part of the operation of
M_newTensorSpec
, so your original string need not remain valid after the completion of this call.
 Returns:
A pointer to the tensor spec. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeTensorSpec()
.

int64_t M_getDimAt(const M_TensorSpec *spec, size_t axis)¶
Gets the element at a particular axis.
 Parameters:
spec – The tensor spec.
axis – The requested axis
 Returns:
The dimension at requested axis if the spec and axis are valid. Otherwise,
0
. A dimension of 1 indicates dynamic dimension e.g. batchsize of a model expecting a batched tensor.

size_t M_getRank(const M_TensorSpec *spec)¶
Gets the rank from the tensor spec.
 Parameters:
spec – The tensor spec.
 Returns:
The number of dimensions in the tensor spec if the spec is valid. Otherwise,
0
.

M_Dtype M_getDtype(const M_TensorSpec *spec)¶
Gets the datatype from the tensor spec.
 Parameters:
spec – The tensor spec.
 Returns:
The element type from the tensor spec if the tensor spec is valid. Otherwise,
M_UNKNOWN
.

const char *M_getName(M_TensorSpec *spec)¶
Gets the name of the tensor from the tensor spec.
 Parameters:
spec – The tensor spec.
 Returns:
A nullterminated string containing the name of the tensor if the
spec
is valid. Otherwise,NULL
. The memory associated with the returned string is owned byspec
.

M_AsyncTensorMap *M_newAsyncTensorMap(const M_RuntimeContext *context)¶
Creates a map of tensor names to async tensors.
 Parameters:
context – The runtime context.
size – The size of the collection.
 Returns:
A pointer to the tensor map. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeAsyncTensorMap()
.

size_t M_getTensorMapSize(const M_AsyncTensorMap *tensorMap, M_Status *status)¶
Gets the size of the tensor map.
 Parameters:
tensorMap – The tensor map.
status – The status object for reporting errors.
 Returns:
The size of the tensor map if the tensor map is valid. Otherwise,
0
and thestatus
parameter contains an error message.

void M_borrowTensorInto(M_AsyncTensorMap *tensors, const void *input, const M_TensorSpec *tensorSpec, M_Status *status)¶
Adds a tensor to the tensor map.
You are responsible for the lifetime of the input tensor data. Its data gets “borrowed” into the Tensor Map.
 Parameters:
tensors – The tensor map, from
M_newAsyncTensorMap()
.input – The input tensor data.
tensorSpec – The tensor spec, from
M_newTensorSpec()
. This gets copied as part of the operation ofM_borrowTensorInto
, so your original tensorSpec need not exist through the lifetime of the tensor map.status – The status object for reporting errors.

M_AsyncValue *M_createBorrowedTensor(const void *data, const M_TensorSpec *tensorSpec, M_RuntimeContext *context)¶
Creates a borrowed tensor wrapped in an
AsyncValue
. Parameters:
data – The tensor data.
tensorSpec – The tensor spec, from
M_newTensorSpec()
. This gets copied as part of the operation ofM_createBorrowedTensor
, so your original tensorSpec need not exist through the lifetime of the tensor.context – The runtime context.
 Returns:
A pointer to the value. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeValue()
. The held value inside the return value is owned by theAsyncValue
, however the tensor data is borrowed and must outlive the returnedM_AsyncValue
.

M_AsyncTensor *M_getTensorByNameFrom(M_AsyncTensorMap *tensorMap, const char *name, M_Status *status)¶
Gets a tensor from the tensor map by name.
 Parameters:
tensorMap – The tensor map.
tensorName – The name of the tensor.
status – The status object for reporting errors.
 Returns:
A pointer to the tensor. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeTensor()
. The held tensor inside the return value is simply borrowed from the corresponding inputM_AsyncTensorMap
. If the tensor map or name are invalid, aNULL
pointer is returned and thestatus
parameter contains an error message.

M_AsyncTensor *M_getTensorFromValue(M_AsyncValue *value)¶
Gets a tensor from the async value.
 Parameters:
value – The async value.
 Returns:
A pointer to the tensor. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeTensor()
. The held tensor inside the return value is simply borrowed from theM_AsyncValue
. Note that the tensor name is not available through this method (unlikeM_getTensorByNameFrom
). If the value is invalid or not a tensor, aNULL
pointer is returned.

size_t M_getTensorNumElements(const M_AsyncTensor *tensor)¶
Gets the number of elements for the tensor.
 Parameters:
tensor – The tensor which must not be
NULL
. Returns:
The number of elements for the given tensor.

M_Dtype M_getTensorType(const M_AsyncTensor *tensor)¶
Gets the corresponding
M_Dtype
for the tensor. Parameters:
tensor – The tensor which must not be
NULL
. Returns:
The corresponding
M_Dtype
for the tensor.

const void *M_getTensorData(const M_AsyncTensor *tensor)¶
Gets a pointer to underlying data of the tensor.
 Parameters:
tensor – The tensor which must not be
NULL
. Returns:
A pointer to the underlying data of the tensor. This pointer is valid for the lifetime of the underlying tensor.

M_TensorSpec *M_getTensorSpec(const M_AsyncTensor *tensor)¶
Gets a Tensor Spec for the tensor.
 Parameters:
tensor – The tensor.
 Returns:
The tensor spec for the tensor if the tensor is valid. Otherwise,
NULL
.

M_TensorMapIterator *M_getTensorMapIterator(M_AsyncTensorMap *tensorMap, M_Status *status)¶
Gets a tensor map iterator for the tensor map.
 Parameters:
tensorMap – The tensor map.
status – The status object for reporting errors.
 Returns:
A pointer to the tensor map iterator. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeTensorMapIterator()
. If the tensor map is invalid, aNULL
pointer is returned and thestatus
parameter contains an error message.

void M_advanceTensorMapIterator(M_TensorMapIterator *iterator)¶
Advances the tensor map iterator by one entry.
 Parameters:
iterator – The tensor map iterator.

const char *M_getNameFromMapIterator(M_TensorMapIterator *iterator)¶
Gets the name of the tensor from the tensor map iterator.
 Parameters:
iterator – The tensor map iterator.
 Returns:
A nullterminated string containing the name of the tensor if the
iterator
is valid. Otherwise,NULL
. The memory associated with the returned string is owned byspec
.

M_AsyncTensor *M_getTensorFromMapIterator(M_TensorMapIterator *iterator)¶
Gets the tensor from the tensor map iterator.
 Parameters:
iterator – The tensor map iterator.
 Returns:
A pointer to the tensor. You are responsible for the memory associated with the pointer returned. The memory can be deallocated by calling
M_freeTensor()
. The held tensor inside the return value is simply borrowed from the corresponding inputM_AsyncTensorMap
. If the tensor map iterator is invalid, aNULL
pointer is returned.

bool M_isEndOfTensorMap(M_AsyncTensorMap *tensorMap, M_TensorMapIterator *iterator)¶
Checks if the iterator has reached the end of the tensor map.
 Parameters:
tensorMap – The tensor map.
iterator – The tensor map iterator.
 Returns:
True if the iterator points to the end of the map, false otherwise. Also returns true if either the tensorMap or iterator are invalid.

void M_freeTensor(M_AsyncTensor *tensor)¶
Deallocates the memory for the tensor. Noop if
tensor
is NULL. Parameters:
tensor – The tensor to deallocate.

void M_freeTensorNameArray(M_TensorNameArray *names)¶
Deallocates the memory for the array of tensor names. Noop if
names
is NULL. Parameters:
names – The tensor names to deallocate.

void M_freeTensorSpec(M_TensorSpec *spec)¶
Deallocates the memory for the tensor spec. Noop if
spec
is NULL. Parameters:
spec – The tensor spec to deallocate.

void M_freeAsyncTensorMap(M_AsyncTensorMap *tensorMap)¶
Deallocates the memory for the tensor map. Noop if
tensorMap
is NULL. Parameters:
tensorMap – The tensor map to deallocate.

void M_freeTensorMapIterator(M_TensorMapIterator *iterator)¶
Deallocates the memory for the tensor map iterator. Noop if
iterator
is NULL. Parameters:
iterator – The tensor map iterator to deallocate.