Function NewTensor

tensorflow/go/tensor.go:72–113

NewTensor converts from a Go value to a Tensor. Valid values are scalars, slices, and arrays. Every element of a slice must have the same length so that the resulting Tensor has a valid shape.

(value interface{})

// slices, and arrays. Every element of a slice must have the same length so
// that the resulting Tensor has a valid shape.
func NewTensor(value interface{}) (*Tensor, error) {
	val := reflect.ValueOf(value)
	shape, dataType, err := shapeAndDataTypeOf(val)
	if err != nil {
		return nil, err
	}
	nflattened := numElements(shape)
	nbytes := typeOf(dataType, nil).Size() * uintptr(nflattened)
	if dataType == String {
		// TF_STRING tensors are encoded as an array of 8-byte offsets
		// followed by string data. See c_api.h.
		nbytes = uintptr(nflattened*8) + byteSizeOfEncodedStrings(value)
	}
	var shapePtr *C.int64_t
	if len(shape) > 0 {
		shapePtr = (*C.int64_t)(unsafe.Pointer(&shape[0]))
	}
	t := &Tensor{
		c:     C.TF_AllocateTensor(C.TF_DataType(dataType), shapePtr, C.int(len(shape)), C.size_t(nbytes)),
		shape: shape,
	}
	runtime.SetFinalizer(t, (*Tensor).finalize)
	raw := tensorData(t.c)
	buf := bytes.NewBuffer(raw[:0:len(raw)])
	if dataType != String {
		if err := encodeTensor(buf, val, shape); err != nil {
			return nil, err
		}
		if uintptr(buf.Len()) != nbytes {
			return nil, bug("NewTensor incorrectly calculated the size of a tensor with type %v and shape %v as %v bytes instead of %v", dataType, shape, nbytes, buf.Len())
		}
	} else {
		e := stringEncoder{offsets: buf, data: raw[nflattened*8:], status: newStatus()}
		if err := e.encode(reflect.ValueOf(value), shape); err != nil {
			return nil, err
		}
		if int64(buf.Len()) != nflattened*8 {
			return nil, bug("invalid offset encoding for TF_STRING tensor with shape %v (got %v, want %v)", shape, buf.Len(), nflattened*8)
		}
	}
	return t, nil
}

// ReadTensor constructs a Tensor with the provided type and shape from the
// serialized tensor contents in r.