calculate

Performs calculation using basic operators. Currently, the following calculations are supported: cryptographic multiplication, comparison, division, averaging, summation, and sorting.

int calculate(
	DG_TeeCtx *dgTeeCtx,
        DG_AlgorithmsType type,
        DG_MpcShareSet *shareSet,
        DG_MpcShare **share
)

Parameters

**Table 1** Description
Parameter	Description	Value Range	Input/Output
dgTeeCtx	KCAL context	Context initialized in section initTeeCtx.	Input
type	Operator enumeration: DG_AlgorithmsType	MULTI // Multiplication operator DIV // Division operator LT // Less than operator LT_EQ // Less than or equal to operator GT // Greater than operator GT_EQ // Greater than or equal to operator EQ // Equal to operator NEQ // Not equal to operator AVG // Average operator SUM // Sum operator ASCEND_SORT // Sort ascending operator DESCEND_SORT // Sort descending operator	Input
shareSet	The type of the structure after concatenating the shares: DG_MpcShareSet	The value is not null.	Input
share	The type of the calculation result: DG_MpcShare	It is null as a single pointer and cannot be null as a double pointer.	Output

**Table 2** DG_MpcShareSet structure
Member	Type	Description
shareSet	DG_MpcShare	Shares of each participant
size	unsigned long	Number of participants

**Table 3** DG_MpcShare structure
Member	Type	Description
dataShare	Share*	Share structure
size	unsigned long	Data volume
shareType	DG_ShareType	Share type

Return Values

Success: 0 is returned.
Failure: The error code is returned.

Error Codes

**Table 4** Error codes
Error Code	Value	Description	Remarks
DG_ERR_MPC_TEE_INVALID_PARAM	4501	Invalid parameter	-
DG_ERR_MPC_TEE_INVALID_ALGORITHM_TYPE	4502	Invalid algorithm type	-
DG_ERR_MALLOC_FAIL	51	Memory allocation failure	-
DG_ERR_MPC_DIVISION_BY_ZERO	4020	Division by zero error	-
DG_FAILURE	4501	Operator execution failure	Failed to verify the parameters. Failed to share data. Failed to receive data from the other node.

Dependency

Call the calculate API using the dgTeeCtx output from the successful initTeeCtx call.
The share output indicates the data share of a single party. You need to call the makeShare API multiple times and concatenate the DG_MpcShare data from both parties into the DG_MpcShareSet. The concatenation order is crucial. For example, after compute node 0 acquires share a, it calls the less-than operator to confirm that a < b (a originates from compute node 1 and b from compute node 0), and then places share a at bit 0 and share b at bit 1 in DG_MpcShareSet.
The basic operations involve two parties.

Example

#include  "data_guard_mpc.h" 
// Compute party
DG_AlgorithmsType type = MULTI;
std::unique_ptr<DG_MpcShareSet> shares = std::make_unique<DG_MpcShareSet>();
std::unique_ptr<DG_MpcShare[]> share_datas = std::make_unique<DG_MpcShare[]>(2);
share_datas[0] = *share2;
share_datas[1] = *share1;
shares->shareSet = share_datas.get();
shares->size = 2;   
DG_MpcShare *share_out = nullptr;
res = aritOpts.calculate(dgTee, type, shares.get(), &share_out);

The calculation is based on the multiplication operator. In the example, shares 1 and 2 serve as examples for reference but cannot be executed.

Running result: The shares are not null and res is 0.

Parent topic: Arithmetic Operators