C++ API Reference¶

This page describes all classes, enumerators and functions available in dtFFT C++ API. In order to use them user have to #include <dtfft.hpp>. All API is contained within dtfft namespace.

Predefined Macros¶

DTFFT_CXX_CALL(call)¶

Safe call macro.

Should be used to check error codes returned by dtFFT.

Throws an exception with a message explaining the error if one occurs.

Example

DTFFT_CXX_CALL( plan.execute(a, b, dtfft::Execute::FORWARD) )

Enumerators¶

enum class dtfft::Error¶

This enum lists the different error codes that dtFFT can return.

Values:

enumerator SUCCESS¶: Successful execution.

enumerator MPI_FINALIZED¶: MPI_Init is not called or MPI_Finalize has already been called.

enumerator PLAN_NOT_CREATED¶: Plan not created.

enumerator INVALID_TRANSPOSE_TYPE¶: Invalid transpose_type provided.

enumerator INVALID_N_DIMENSIONS¶

Invalid Number of dimensions provided.

Valid options are 2 and 3

enumerator INVALID_DIMENSION_SIZE¶: One or more provided dimension sizes <= 0.

enumerator INVALID_COMM_TYPE¶: Invalid communicator type provided.

enumerator INVALID_PRECISION¶: Invalid precision parameter provided.

enumerator INVALID_EFFORT¶: Invalid effort parameter provided.

enumerator INVALID_EXECUTOR¶: Invalid executor parameter provided.

enumerator INVALID_COMM_DIMS¶: Number of dimensions in provided Cartesian communicator > Number of dimension passed to create subroutine.

enumerator INVALID_COMM_FAST_DIM¶: Passed Cartesian communicator with number of processes in 1st (fastest varying) dimension > 1.

enumerator MISSING_R2R_KINDS¶: For R2R plan, kinds parameter must be passed if executor != Executor::NONE

enumerator INVALID_R2R_KINDS¶: Invalid values detected in kinds parameter.

enumerator R2C_TRANSPOSE_PLAN¶: Transpose plan is not supported in R2C, use R2R or C2C plan instead.

enumerator INPLACE_TRANSPOSE¶: Inplace transpose is not supported.

enumerator INVALID_AUX¶: Invalid aux buffer provided.

enumerator INVALID_DIM¶: Invalid dim passed to Plan.get_pencil

enumerator INVALID_USAGE¶: Invalid API Usage.

enumerator PLAN_IS_CREATED¶: Trying to create already created plan.

enumerator R2R_FFT_NOT_SUPPORTED¶: Selected executor does not support R2R FFTs.

enumerator ALLOC_FAILED¶: Internal call of Plan.mem_alloc failed.

enumerator DLOPEN_FAILED¶: Failed to dynamically load library.

enumerator DLSYM_FAILED¶: Failed to dynamically load symbol.

enumerator R2C_TRANSPOSE_CALLED¶: Calling to Plan.transpose for R2C plan is not allowed.

enumerator FREE_FAILED¶: Internal call of Plan.mem_free failed.

enumerator INVALID_ALLOC_BYTES¶: Invalid alloc_bytes provided.

enumerator GPU_INVALID_STREAM¶: Invalid stream provided.

enumerator GPU_INVALID_BACKEND¶: Invalid GPU backend provided.

enumerator GPU_NOT_SET¶: Multiple MPI Processes located on same host share same GPU which is not supported.

enumerator VKFFT_R2R_2D_PLAN¶: When using R2R FFT and executor type is vkFFT and plan uses Z-slab optimization, it is required that types of R2R transform are same in X and Y directions.

enumerator GPU_BACKENDS_DISABLED¶: Passed effort == Effort::PATIENT but all GPU backends have been disabled by Config

enumerator NOT_DEVICE_PTR¶: One of pointers passed to Plan.execute or Plan.transpose cannot be accessed from device.

enumerator NOT_NVSHMEM_PTR¶: One of pointers passed to Plan.execute or Plan.transpose is not an NVSHMEM pointer.

enumerator INVALID_PLATFORM¶: Invalid platform provided.

enumerator INVALID_PLATFORM_EXECUTOR_TYPE¶: Invalid executor provided for selected platform.

enum class dtfft::Execute¶

This enum lists valid execute_type parameters that can be passed to Plan.execute.

Values:

enumerator FORWARD¶: Perform XYZ –> YXZ –> ZXY plan execution (Forward)

enumerator BACKWARD¶: Perform ZXY –> YXZ –> XYZ plan execution (Backward)

enum class dtfft::Transpose¶

This enum lists valid transpose_type parameters that can be passed to Plan.transpose.

Values:

enumerator X_TO_Y¶: Transpose from Fortran X aligned to Fortran Y aligned.

enumerator Y_TO_X¶: Transpose from Fortran Y aligned to Fortran X aligned.

enumerator Y_TO_Z¶: Transpose from Fortran Y aligned to Fortran Z aligned.

enumerator Z_TO_Y¶: Transpose from Fortran Z aligned to Fortran Y aligned.

enumerator X_TO_Z¶: Transpose from Fortran X aligned to Fortran Z aligned.

Note

This value is valid to pass only in 3D Plan and value returned by Plan.get_z_slab_enabled must be true

enumerator Z_TO_X¶: Transpose from Fortran Z aligned to Fortran X aligned.

Note

This value is valid to pass only in 3D Plan and value returned by Plan.get_z_slab_enabled must be true

enum class dtfft::Precision¶

This enum lists valid precision parameters that can be passed to Plan constructors.

Values:

enumerator SINGLE¶: Use Single precision.

enumerator DOUBLE¶: Use Double precision.

enum class dtfft::Effort¶

This enum lists valid effort parameters that can be passed to Plan constructors.

Values:

enumerator ESTIMATE¶: Create plan as fast as possible.

enumerator MEASURE¶

Will attempt to find best MPI Grid decomposition.

Passing this flag and MPI Communicator with cartesian topology to any Plan Constructor is same as Effort::ESTIMATE.

enumerator PATIENT¶

Same as Effort::MEASURE plus cycle through various send and receive MPI_Datatypes.

For GPU Build this flag will run autotune procedure to find best backend

enum class dtfft::Executor¶

This enum lists available FFT executors.

Values:

enumerator NONE¶

Do not create any FFT plans.

Creates transpose only plan.

enumerator FFTW3¶: FFTW3 Executor (Host only)

enumerator MKL¶: MKL DFTI Executor (Host only)

enumerator CUFFT¶: CUFFT Executor (GPU Only)

enumerator VKFFT¶: VkFFT Executor (GPU Only)

enum class dtfft::R2RKind¶

Real-to-Real FFT kinds available in dtFFT.

Values:

enumerator DCT_1¶: DCT-I (Logical N=2*(n-1), inverse is R2RKind::DCT_1)

enumerator DCT_2¶: DCT-II (Logical N=2*n, inverse is R2RKind::DCT_3)

enumerator DCT_3¶: DCT-III (Logical N=2*n, inverse is R2RKind::DCT_2)

enumerator DCT_4¶: DCT-IV (Logical N=2*n, inverse is R2RKind::DCT_4)

enumerator DST_1¶: DST-I (Logical N=2*(n+1), inverse is R2RKind::DST_1)

enumerator DST_2¶: DST-II (Logical N=2*n, inverse is R2RKind::DST_3)

enumerator DST_3¶: DST-III (Logical N=2*n, inverse is R2RKind::DST_2)

enumerator DST_4¶: DST-IV (Logical N=2*n, inverse is R2RKind::DST_4)

enum class dtfft::Backend¶

Various Backends available in dtFFT.

Note

This enum is only present in the API when dtFFT was compiled with CUDA Support.

Values:

enumerator MPI_DATATYPE¶

Backend that uses MPI datatypes.

Not really recommended to use, since it is a million times slower than other backends. It is present here just to show how slow MPI Datatypes are for GPU usage

enumerator MPI_P2P¶: MPI peer-to-peer algorithm.

enumerator MPI_P2P_PIPELINED¶: MPI peer-to-peer algorithm with overlapping data copying and unpacking.

enumerator MPI_A2A¶: MPI backend using MPI_Alltoallv.

enumerator NCCL¶: NCCL backend.

enumerator NCCL_PIPELINED¶: NCCL backend with overlapping data copying and unpacking.

enumerator CUFFTMP¶: cuFFTMp backend

enum class dtfft::Platform¶

Enum that specifies runtime platform, e.g.

Host, CUDA, HIP

Values:

enumerator HOST¶: Host.

enumerator CUDA¶: CUDA.

Functions¶

std::string dtfft::get_backend_string(const Backend backend)¶

Returns string with name of backend provided as argument.

Note

This function is only present in the API when dtFFT was compiled with CUDA Support.

Parameters:: backend – [in] Backend to represent
Returns:: String representation of backend.

inline std::string dtfft::get_error_string(Error error_code) noexcept¶

Returns the string description of an error code.

Parameters:: error_code – [in] Error code to convert to string
Returns:: String representation of error_code

inline Error dtfft::set_config(Config config) noexcept¶

Sets configuration values to dtFFT.

Must be called before plan creation to take effect.

Classes¶

class Version¶

dtFFT version information

Public Static Functions

static inline int32_t get() noexcept¶

Returns:: Version Code defined during compilation

static inline constexpr int32_t get(int32_t major, int32_t minor, int32_t patch) noexcept¶

Returns:: Version Code based on input parameters

Public Static Attributes

static constexpr int32_t MAJOR = DTFFT_VERSION_MAJOR¶: dtFFT Major Version

static constexpr int32_t MINOR = DTFFT_VERSION_MINOR¶: dtFFT Minor Version

static constexpr int32_t PATCH = DTFFT_VERSION_PATCH¶: dtFFT Patch Version

static constexpr int32_t CODE = DTFFT_VERSION_CODE¶

dtFFT Version Code.

Can be used for version comparison

class Exception : public std::exception¶

Basic exception class.

Public Functions

inline Exception(std::string msg, const char *file, int line)¶

Basic exception constructor.

Parameters:

msg – Message describing the error that occurred
file – Filename
line – Line number

inline const char *what() const noexcept override¶: Exception explanation.

class Pencil¶

Class to handle Pencils.

See also

set_config()

Public Functions

inline Config &set_enable_z_slab(bool enable_z_slab) noexcept¶

Sets whether dtFFT use Z-slab optimization or not.

Default is true

One should consider disabling Z-slab optimization in order to resolve Error::VKFFT_R2R_2D_PLAN error OR when underlying FFT implementation of 2D plan is too slow.

In all other cases it is considered that Z-slab is always faster, since it reduces number of data transpositions.

inline Config &set_platform(Platform platform) noexcept¶

Sets platform to execute plan.

Default is Platform::HOST

This option is only defined with device support build. Even when dtFFT is build with device support it does not necessary means that all plans must be related to device.

inline Config &set_stream(dtfft_stream_t stream) noexcept¶

Sets Main CUDA stream that will be used in dtFFT.

This parameter is a placeholder for user to set custom stream. Stream that is actually used by dtFFT plan is returned by Plan.get_stream function. When user sets stream he is responsible of destroying it.

Stream must not be destroyed before call to destroy.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

inline Config &set_backend(Backend backend) noexcept¶

Sets GPU Backend that will be used by dtFFT when effort is Effort::ESTIMATE or Effort::MEASURE.

Default is Backend::NCCL

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

inline Config &set_enable_mpi_backends(bool enable_mpi_backends) noexcept¶

Sets whether MPI GPU Backends be enabled when effort is DTFFT_PATIENT or not.

Default is false

MPI Backends are disabled by default during autotuning process due to OpenMPI Bug https://github.com/open-mpi/ompi/issues/12849 It was noticed that during plan autotuning GPU memory not being freed completely.

For example: 1024x1024x512 C2C, double precision, single GPU, using Z-slab optimization, with MPI backends enabled, plan autotuning will leak 8Gb GPU memory. Without Z-slab optimization, running on 4 GPUs, will leak 24Gb on each of the GPUs.

One of the workarounds is to disable MPI Backends by default, which is done here.

Other is to pass “–mca btl_smcuda_use_cuda_ipc 0” to mpiexec, but it was noticed that disabling CUDA IPC seriously affects overall performance of MPI algorithms

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

inline Config &set_enable_pipelined_backends(bool enable_pipelined_backends) noexcept¶

Sets whether pipelined GPU backends be enabled when effort is Effort::PATIENT or not.

Default is true

Note

Pipelined backends require additional buffer that user has no control over.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

inline Config &set_enable_nccl_backends(bool enable_nccl_backends) noexcept¶

Sets whether NCCL Backends be enabled when effort is Effort::PATIENT or not.

Default is true.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

inline Config &set_enable_nvshmem_backends(bool enable_nvshmem_backends) noexcept¶

Should NVSHMEM Backends be enabled when effort is Effort::PATIENT or not.

Default is true.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

inline dtfft_config_t c_struct() const¶

Returns:: Underlying C structure

class Plan¶

Abstract plan for all dtFFT plans.

This class does not have any constructors. To create a plan user should use one of the inherited classes.

Subclassed by dtfft::PlanC2C, dtfft::PlanR2C, dtfft::PlanR2R

Public Functions

inline Error get_z_slab_enabled(bool *is_z_slab_enabled) const noexcept¶

Checks if plan is using Z-slab optimization.

If true then flags Transpose::X_TO_Z and Transpose::Z_TO_X will be valid to pass to Plan.transpose method.

Parameters:: is_z_slab_enabled – [out] Boolean value if Z-slab is used.
Returns:: Error::SUCCESS if call was without error, error code otherwise

inline bool get_z_slab_enabled() const¶

Checks if plan is using Z-slab optimization.

Throws:: Exception – if underlying call fails
Returns:: true if Z-slab is enabled, false otherwise

inline Error report() const noexcept¶

Prints plan-related information to stdout.

Returns:: Error::SUCCESS if call was without error, error code otherwise

inline Error get_pencil(const int32_t dim, Pencil &pencil) const noexcept¶

Obtains pencil information from plan.

This can be useful when user wants to use own FFT implementation, that is unavailable in dtFFT.

Parameters:

dim – [in] Required dimension:
- 0 for XYZ layout (real space, R2C only)
- 1 for XYZ layout
- 2 for YXZ layout
- 3 for ZXY layout
pencil – [out] Pencil class

Returns:

Error::SUCCESS on success or error code on failure.

inline Pencil get_pencil(const int32_t dim) const¶

Get the pencil object.

Parameters:

dim – [in] Required dimension:

0 for XYZ layout (real space, R2C only)
1 for XYZ layout
2 for YXZ layout
3 for ZXY layout

Throws:

Exception – if underlying call fails

Returns:

Pencil class

inline Error execute(void *in, void *out, const Execute execute_type, void *aux = nullptr) const noexcept¶

Plan execution.

Note

Parameters:

in – [inout] Incoming pointer
out – [out] Result pointer
execute_type – [in] Type of execution
aux – [inout] Optional auxiliary pointer

Returns:

Error::SUCCESS on success or error code on failure.

inline Error transpose(void *in, void *out, const Transpose transpose_type) const noexcept¶

Transpose data in single dimension, e.g.

X align -> Y align

Attention: in and out cannot be the same pointers

Parameters:

in – [inout] Incoming pointer
out – [out] Transposed pointer
transpose_type – [in] Type of transpose to perform.

Returns:

Error::SUCCESS on success or error code on failure.

inline Error get_alloc_size(size_t *alloc_size) const noexcept¶

Wrapper around Plan.get_local_sizes to obtain alloc_size only.

Parameters:: alloc_size – [out] Minimum number of elements to be allocated for in, out or aux buffers. Size of each element in bytes can be obtained by calling Plan.get_element_size.
Returns:: Error::SUCCESS on success or error code on failure.

inline size_t get_alloc_size() const¶

Wrapper around Plan.get_local_sizes to obtain alloc_size only.

Throws:: Exception – if underlying call fails
Returns:: Minimum number of elements to be allocated for in, out or aux buffers.

inline Error get_local_sizes(std::vector<int32_t> &in_starts, std::vector<int32_t> &in_counts, std::vector<int32_t> &out_starts, std::vector<int32_t> &out_counts, size_t *alloc_size) const noexcept¶

Get grid decomposition information.

Results may differ on different MPI processes

Note

Before calling this function, user must ensure that in_starts, in_counts, out_starts and out_counts vectors are large enough to hold the data.

Parameters:

in_starts – [out] Starts of local portion of data in ‘real’ space in reversed order
in_counts – [out] Sizes of local portion of data in ‘real’ space in reversed order
out_starts – [out] Starts of local portion of data in ‘fourier’ space in reversed order
out_counts – [out] Sizes of local portion of data in ‘fourier’ space in reversed order
alloc_size – [out] Minimum number of elements to be allocated for in, out or aux buffers. Size of each element in bytes can be obtained by calling Plan.get_element_size.

Returns:

Error::SUCCESS on success or error code on failure.

inline Error get_local_sizes(int32_t *in_starts = nullptr, int32_t *in_counts = nullptr, int32_t *out_starts = nullptr, int32_t *out_counts = nullptr, size_t *alloc_size = nullptr) const noexcept¶

Get grid decomposition information.

Results may differ on different MPI processes

Parameters:

in_starts – [out] Starts of local portion of data in ‘real’ space in reversed order
in_counts – [out] Sizes of local portion of data in ‘real’ space in reversed order
out_starts – [out] Starts of local portion of data in ‘fourier’ space in reversed order
out_counts – [out] Sizes of local portion of data in ‘fourier’ space in reversed order
alloc_size – [out] Minimum number of elements needs to be allocated for in, out or aux buffers. Size of each element in bytes can be obtained by calling Plan.get_element_size.

Returns:

Error::SUCCESS on success or error code on failure.

inline Error get_element_size(size_t *element_size) const noexcept¶

Obtains number of bytes required to store single element by this plan.

Parameters:: element_size – [out] Size of element in bytes
Returns:: Error::SUCCESS on success or error code on failure.

inline size_t get_element_size() const¶

Obtains number of bytes required to store single element by this plan.

Throws:: Exception – if underlying call fails
Returns:: Size of element in bytes

inline Error get_alloc_bytes(size_t *alloc_bytes) const noexcept¶

Returns minimum number of bytes required to execute plan.

This function is a combination of two calls: Plan.get_alloc_size and Plan.get_element_size

Parameters:: alloc_bytes – [out] Number of bytes required
Returns:: Error::SUCCESS on success or error code on failure.

inline size_t get_alloc_bytes() const¶

Returns minimum number of bytes required to execute plan.

This function is a combination of two calls: Plan.get_alloc_size and Plan.get_element_size

Throws:: Exception – if underlying call fails
Returns:: Number of bytes of each buffer required to execute plan

inline Error mem_alloc(size_t alloc_bytes, void **ptr) const noexcept¶

Allocates memory specific for this plan.

Parameters:

alloc_bytes – [in] Number of bytes to allocate
ptr – [out] Allocated pointer

Returns:

Error::SUCCESS on success or error code on failure.

inline void *mem_alloc(size_t alloc_bytes) const¶

Allocates memory specific for this plan.

Parameters:: alloc_bytes – Number of bytes to allocate
Returns:: void* Pointer to allocated memory

inline Error mem_free(void *ptr) const noexcept¶

Frees memory specific for this plan.

Parameters:: ptr – [inout] Allocated pointer
Returns:: Error::SUCCESS on success or error code on failure.

inline Error destroy() noexcept¶

Plan Destructor.

To fully clean all internal memory, this should be called before MPI_Finalize

Returns:: Error::SUCCESS on success or error code on failure.

inline Error get_stream(dtfft_stream_t *stream) const noexcept¶

Returns stream associated with current Plan.

This can either be stream passed by Config.set_stream followed by set_config() or stream created internally. Returns NULL pointer if plan’s platform is Platform::HOST.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

Parameters:: stream – [out] CUDA stream associated with plan
Returns:: Error::SUCCESS on success or error code on failure.

inline dtfft_stream_t get_stream() const¶

Returns stream associated with current Plan.

This can either be stream passed by Config.set_stream followed by set_config() or stream created internally. Returns NULL pointer if plan’s platform is Platform::HOST.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

Returns:: dtFFT stream associated with plan

inline Error get_backend(Backend &backend) const noexcept¶

Returns selected GPU backend during autotune if effort is Effort::PATIENT.

If effort passed to any create function is Effort::ESTIMATE or Effort::MEASURE returns value set by Config.set_backend followed by set_config() or default value, which is Backend::NCCL.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

Returns:: Error::SUCCESS on success or error code on failure.

inline Backend get_backend() const¶

Returns selected GPU backend during autotune if effort is Effort::PATIENT.

If effort passed to any create function is Effort::ESTIMATE or Effort::MEASURE returns value set by Config.set_backend followed by set_config() or default value, which is Backend::NCCL.

Note

This method is only present in the API when dtFFT was compiled with CUDA Support.

Throws:: Exception – if underlying call fails
Returns:: GPU Backend used by this plan.

inline Error get_platform(Platform &platform) const noexcept¶

Returns plan execution platform.

Returns:: DTFFT_SUCCESS on success or error code on failure.

inline Platform get_platform() const¶

Returns plan execution platform.

Throws:: Exception – if underlying call fails
Returns:: Platform::HOST if plan is executed on host, Platform::CUDA if plan is executed on CUDA device.

inline dtfft_plan_t c_struct() const¶

Returns:: Underlying C structure

inline virtual ~Plan() noexcept = 0¶

Plan Destructor.

To fully clean all internal memory, this should be called before MPI_Finalize

class PlanC2C : public dtfft::Plan ¶

Complex-to-Complex Plan.

Public Functions

inline explicit PlanC2C(const std::vector<int32_t> &dims, MPI_Comm comm = MPI_COMM_WORLD, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE, const Executor executor = Executor::NONE)¶

Complex-to-Complex Plan constructor.

Parameters:

dims – [in] Vector with global dimensions in reversed order. dims.size() must be 2 or 3
comm – [in] MPI communicator: MPI_COMM_WORLD or Cartesian communicator
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan
executor – [in] Type of external FFT executor

Throws:

Exception – In case error occurs during plan creation

inline explicit PlanC2C(const std::vector<int32_t> &dims, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE)¶

Complex-to-Complex Transpose-only Plan constructor.

Parameters:

dims – [in] Vector with global dimensions in reversed order. dims.size() must be 2 or 3
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan

Throws:

Exception – In case error occurs during plan creation

inline explicit PlanC2C(const int8_t ndims, const int32_t *dims, MPI_Comm comm = MPI_COMM_WORLD, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE, const Executor executor = Executor::NONE)¶

Complex-to-Complex Generic Plan constructor.

Parameters:

ndims – [in] Number of dimensions: 2 or 3
dims – [in] Buffer of size ndims with global dimensions in reversed order.
comm – [in] MPI communicator: MPI_COMM_WORLD or Cartesian communicator
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan
executor – [in] Type of external FFT executor

Throws:

Exception – In case error occurs during plan creation

class PlanR2C : public dtfft::Plan ¶

Real-to-Complex Plan.

Note

This class is only present in the API when dtFFT was compiled with any external FFT.

Public Functions

inline explicit PlanR2C(const std::vector<int32_t> &dims, const Executor executor, MPI_Comm comm = MPI_COMM_WORLD, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE)¶

Real-to-Complex Plan constructor.

Note

Parameter executor cannot be Executor::NONE. PlanC2C should be used instead.

Parameters:

dims – [in] Vector with global dimensions in reversed order. dims.size() must be 2 or 3
comm – [in] MPI communicator: MPI_COMM_WORLD or Cartesian communicator
executor – [in] Type of external FFT executor
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan

Throws:

Exception – In case error occurs during plan creation

inline explicit PlanR2C(const int8_t ndims, const int32_t *dims, const Executor executor, MPI_Comm comm = MPI_COMM_WORLD, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE)¶

Real-to-Complex Generic Plan constructor.

Note

Parameter executor cannot be Executor::NONE. PlanC2C should be used instead.

Parameters:

ndims – [in] Number of dimensions: 2 or 3
dims – [in] Buffer of size ndims with global dimensions in reversed order.
comm – [in] MPI communicator: MPI_COMM_WORLD or Cartesian communicator
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan
executor – [in] Type of external FFT executor

Throws:

Exception – In case error occurs during plan creation

class PlanR2R : public dtfft::Plan ¶

Real-to-Real Plan.

Public Functions

inline explicit PlanR2R(const std::vector<int32_t> &dims, const std::vector<R2RKind> &kinds = std::vector<R2RKind>(), MPI_Comm comm = MPI_COMM_WORLD, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE, const Executor executor = Executor::NONE)¶

Real-to-Real Plan constructor.

Parameters:

dims – [in] Vector with global dimensions in reversed order. dims.size() must be 2 or 3
kinds – [in] Real FFT kinds in reversed order. Can be empty vector if executor == Executor::NONE
comm – [in] MPI communicator: MPI_COMM_WORLD or Cartesian communicator
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan
executor – [in] Type of external FFT executor.

Throws:

Exception – In case error occurs during plan creation

inline explicit PlanR2R(const std::vector<int32_t> &dims, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE)¶

Real-to-Real Transpose-only Plan constructor.

Parameters:

dims – [in] Vector with global dimensions in reversed order. dims.size() must be 2 or 3
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan

Throws:

Exception – In case error occurs during plan creation

inline explicit PlanR2R(const int8_t ndims, const int32_t *dims, const R2RKind *kinds = nullptr, MPI_Comm comm = MPI_COMM_WORLD, const Precision precision = Precision::DOUBLE, const Effort effort = Effort::ESTIMATE, const Executor executor = Executor::NONE)¶

Real-to-Real Generic Plan constructor.

Parameters:

ndims – [in] Number of dimensions: 2 or 3
dims – [in] Buffer of size ndims with global dimensions in reversed order.
kinds – [in] Buffer of size ndims with Real FFT kinds in reversed order. Can be nullptr if executor == Executor::NONE
comm – [in] MPI communicator: MPI_COMM_WORLD or Cartesian communicator
precision – [in] Precision of transform.
effort – [in] How thoroughly dtFFT searches for the optimal plan
executor – [in] Type of external FFT executor.

Throws:

Exception – In case error occurs during plan creation