for the same data.
when use matlab to read it. it works fine.
uiopen('C:\Users\evelyn\Downloads\wifi.csi',1) Start parsing PicoScenes CSI file: wifi.csi 141117 PicoScenes frames are decoded in 45.4099 seconds. wifi
But with csiread.Picoscenes, it could not give the timestamp. all 'timestamp' are zeros.
`csidata = csiread.Picoscenes(dat_file, {'CSI': [245, 2, 1], 'MPDU': 1522})
csidata.read()
csidata.check()
print(csidata.raw['CSI']['CSI'].shape)
timestamp = csidata.RxSBasic['Timestamp']
rssi_a = csidata.RxSBasic['RSSI1']
rssi_b = csidata.RxSBasic['RSSI2']
csi = csidata.raw['CSI']['CSI']
csi = csi[:, :, :, 0]
`
Use the official parser first. csiread.Picoscenes is not recommended because it's too old and lacks maintenance. At the moment it is just a reference for those who want to implement picoscenes parser in python with higher performance than the official implementation.
Appreciate your immediate help.
Sometimes, the file is too big making crush even for Matlab parse. When I install package, it give below error even with a total new python3.8 virtual environment. Do you have any idea for it?
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:9,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/PicoScenesFrameTxParameters.hxx: In member function ‘void PicoScenesFrameTxParameters::applyPreset(const string&)’:
./rxs_parsing_core/PicoScenesFrameTxParameters.hxx:65:49: error: ‘const class std::map<std::__cxx11::basic_string, std::shared_ptr<FrontEndModePreset> >’ has no member named ‘contains’
if (!FrontEndModePreset::getPresetMap().contains(presetName))
^~~~~~~~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:11,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/CSISegment.hxx: At global scope:
./rxs_parsing_core/CSISegment.hxx:299:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/CSISegment.hxx:299:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/CSISegment.hxx:1:1:
+#include
//
./rxs_parsing_core/CSISegment.hxx:299:36:
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/CSISegment.hxx:299:91: error: template argument 2 is invalid
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/CSISegment.hxx:299:91: error: template argument 4 is invalid
./rxs_parsing_core/CSISegment.hxx:299:92: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/CSISegment.hxx:301:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/CSISegment.hxx:301:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/CSISegment.hxx:301:91: error: template argument 2 is invalid
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/CSISegment.hxx:301:91: error: template argument 4 is invalid
./rxs_parsing_core/CSISegment.hxx:301:92: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<std::shared_ptr<CSI>(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:12,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/RxSBasicSegment.hxx:69:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/RxSBasicSegment.hxx:69:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/RxSBasicSegment.hxx:1:1:
+#include
//
./rxs_parsing_core/RxSBasicSegment.hxx:69:36:
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/RxSBasicSegment.hxx:69:79: error: template argument 2 is invalid
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/RxSBasicSegment.hxx:69:79: error: template argument 4 is invalid
./rxs_parsing_core/RxSBasicSegment.hxx:69:80: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/RxSBasicSegment.hxx:71:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/RxSBasicSegment.hxx:71:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/RxSBasicSegment.hxx:71:79: error: template argument 2 is invalid
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/RxSBasicSegment.hxx:71:79: error: template argument 4 is invalid
./rxs_parsing_core/RxSBasicSegment.hxx:71:80: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<RxSBasic(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:13,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/ExtraInfoSegment.hxx:29:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/ExtraInfoSegment.hxx:29:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/ExtraInfoSegment.hxx:11:1:
+#include
./rxs_parsing_core/ExtraInfoSegment.hxx:29:36:
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/ExtraInfoSegment.hxx:29:80: error: template argument 2 is invalid
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/ExtraInfoSegment.hxx:29:80: error: template argument 4 is invalid
./rxs_parsing_core/ExtraInfoSegment.hxx:29:81: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/ExtraInfoSegment.hxx:31:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/ExtraInfoSegment.hxx:31:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/ExtraInfoSegment.hxx:31:80: error: template argument 2 is invalid
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/ExtraInfoSegment.hxx:31:80: error: template argument 4 is invalid
./rxs_parsing_core/ExtraInfoSegment.hxx:31:81: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<ExtraInfo(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:14,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/MVMExtraSegment.hxx:63:49: error: ‘function’ in namespace ‘std’ does not name a template type
static void setHeaderManipulator(const std::function<void(IntelMVMParsedCSIHeader &)> &headerManipulator);
^~~~~~~~
./rxs_parsing_core/MVMExtraSegment.hxx:63:44: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/MVMExtraSegment.hxx:11:1:
+#include
./rxs_parsing_core/MVMExtraSegment.hxx:63:44:
static void setHeaderManipulator(const std::function<void(IntelMVMParsedCSIHeader &)> &headerManipulator);
^~~
./rxs_parsing_core/MVMExtraSegment.hxx:63:57: error: expected ‘,’ or ‘...’ before ‘<’ token
static void setHeaderManipulator(const std::function<void(IntelMVMParsedCSIHeader &)> &headerManipulator);
^
./rxs_parsing_core/MVMExtraSegment.hxx:72:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<IntelMVMExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/MVMExtraSegment.hxx:72:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/MVMExtraSegment.hxx:72:88: error: template argument 2 is invalid
static std::map<uint16_t, std::function<IntelMVMExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/MVMExtraSegment.hxx:72:88: error: template argument 4 is invalid
./rxs_parsing_core/MVMExtraSegment.hxx:72:89: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<IntelMVMExtraInfo(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/MVMExtraSegment.hxx:74:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<IntelMVMExtraInfo(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/MVMExtraSegment.hxx:74:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/MVMExtraSegment.hxx:74:88: error: template argument 2 is invalid
static std::map<uint16_t, std::function<IntelMVMExtraInfo(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/MVMExtraSegment.hxx:74:88: error: template argument 4 is invalid
./rxs_parsing_core/MVMExtraSegment.hxx:74:89: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<IntelMVMExtraInfo(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~
./rxs_parsing_core/MVMExtraSegment.hxx:76:17: error: ‘function’ in namespace ‘std’ does not name a template type
static std::function<void(IntelMVMParsedCSIHeader &)> headerManipulator;
^~~~~~~~
./rxs_parsing_core/MVMExtraSegment.hxx:76:12: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
static std::function<void(IntelMVMParsedCSIHeader &)> headerManipulator;
^~~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:15,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/SDRExtraSegment.hxx:52:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/SDRExtraSegment.hxx:52:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/SDRExtraSegment.hxx:9:1:
+#include
#include "AbstractPicoScenesFrameSegment.hxx"
./rxs_parsing_core/SDRExtraSegment.hxx:52:36:
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/SDRExtraSegment.hxx:52:79: error: template argument 2 is invalid
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/SDRExtraSegment.hxx:52:79: error: template argument 4 is invalid
./rxs_parsing_core/SDRExtraSegment.hxx:52:80: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/SDRExtraSegment.hxx:54:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/SDRExtraSegment.hxx:54:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/SDRExtraSegment.hxx:54:79: error: template argument 2 is invalid
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/SDRExtraSegment.hxx:54:79: error: template argument 4 is invalid
./rxs_parsing_core/SDRExtraSegment.hxx:54:80: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<SDRExtra(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:17,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/PayloadSegment.hxx:57:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/PayloadSegment.hxx:57:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/PayloadSegment.hxx:1:1:
+#include
//
./rxs_parsing_core/PayloadSegment.hxx:57:36:
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/PayloadSegment.hxx:57:82: error: template argument 2 is invalid
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/PayloadSegment.hxx:57:82: error: template argument 4 is invalid
./rxs_parsing_core/PayloadSegment.hxx:57:83: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/PayloadSegment.hxx:59:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/PayloadSegment.hxx:59:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/PayloadSegment.hxx:59:82: error: template argument 2 is invalid
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/PayloadSegment.hxx:59:82: error: template argument 4 is invalid
./rxs_parsing_core/PayloadSegment.hxx:59:83: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<PayloadData(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:18,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/CargoSegment.hxx:17:46: error: ‘function’ in namespace ‘std’ does not name a template type
static void registerAlgorithm(const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &compressorV,
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:17:41: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/CargoSegment.hxx:1:1:
+#include
//
./rxs_parsing_core/CargoSegment.hxx:17:41:
static void registerAlgorithm(const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &compressorV,
^~~
./rxs_parsing_core/CargoSegment.hxx:17:54: error: expected ‘,’ or ‘...’ before ‘<’ token
static void registerAlgorithm(const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &compressorV,
^
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:18,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/CargoSegment.hxx:26:23: error: ‘function’ in namespace ‘std’ does not name a template type
static const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &getCompressor() {
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:26:18: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
static const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &getCompressor() {
^~~
./rxs_parsing_core/CargoSegment.hxx:30:23: error: ‘function’ in namespace ‘std’ does not name a template type
static const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &getDecompressor() {
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:30:18: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
static const std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> &getDecompressor() {
^~~
./rxs_parsing_core/CargoSegment.hxx:35:17: error: ‘function’ in namespace ‘std’ does not name a template type
static std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> compressor;
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:35:12: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
static std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> compressor;
^~~
./rxs_parsing_core/CargoSegment.hxx:36:17: error: ‘function’ in namespace ‘std’ does not name a template type
static std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> decompressor;
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:36:12: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
static std::function<std::optional<std::vector<uint8_t>>(const uint8_t *, size_t)> decompressor;
^~~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:18,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/CargoSegment.hxx: In static member function ‘static bool CargoCompression::isAlgorithmRegistered()’:
./rxs_parsing_core/CargoSegment.hxx:14:16: error: ‘compressor’ was not declared in this scope
return compressor && decompressor;
^~~~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:14:30: error: ‘decompressor’ was not declared in this scope
return compressor && decompressor;
^~~~~~~~~~~~
In file included from ./rxs_parsing_core/ModularPicoScenesFrame.hxx:18,
from ./picoscenes.cpp:1291:
./rxs_parsing_core/CargoSegment.hxx: In lambda function:
./rxs_parsing_core/CargoSegment.hxx:21:13: error: ‘compressor’ was not declared in this scope
compressor = compressorV;
^~~~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:21:26: error: ‘compressorV’ was not declared in this scope
compressor = compressorV;
^~~~~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:22:13: error: ‘decompressor’ was not declared in this scope
decompressor = decompressorV;
^~~~~~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:22:28: error: ‘decompressorV’ was not declared in this scope
decompressor = decompressorV;
^~~~~~~~~~~~~
./rxs_parsing_core/CargoSegment.hxx: At global scope:
./rxs_parsing_core/CargoSegment.hxx:75:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<std::shared_ptr<PayloadCargo>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:75:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/CargoSegment.hxx:75:100: error: template argument 2 is invalid
static std::map<uint16_t, std::function<std::shared_ptr<PayloadCargo>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^
./rxs_parsing_core/CargoSegment.hxx:75:100: error: template argument 4 is invalid
./rxs_parsing_core/CargoSegment.hxx:75:101: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<std::shared_ptr<PayloadCargo>(const uint8_t *, uint32_t)>> versionedSolutionMap;
^~
./rxs_parsing_core/CargoSegment.hxx:77:36: error: ‘function’ is not a member of ‘std’
static std::map<uint16_t, std::function<std::shared_ptr<PayloadCargo>(const uint8_t *, uint32_t)>> initializeSolutionMap() noexcept;
^~~~~~~~
./rxs_parsing_core/CargoSegment.hxx:77:36: note: ‘std::function’ is defined in header ‘’; did you forget to ‘#include ’?
./rxs_parsing_core/CargoSegment.hxx:77:100: error: template argument 2 is invalid
static std::map<uint16_t, std::function<std::shared_ptr<PayloadCargo>(const uint8_t , uint32_t)>> initializeSolutionMap() noexcept;
^
./rxs_parsing_core/CargoSegment.hxx:77:100: error: template argument 4 is invalid
./rxs_parsing_core/CargoSegment.hxx:77:101: error: expected unqualified-id before ‘>’ token
static std::map<uint16_t, std::function<std::shared_ptr<PayloadCargo>(const uint8_t , uint32_t)>> initializeSolutionMap() noexcept;
^~
./picoscenes.cpp:8776:18: warning: ‘PyObject __pyx_f_10picoscenes_parse_SignalMatrix(const SignalMatrix<std::complex >)’ defined but not used [-Wunused-function]
static PyObject *__pyx_f_10picoscenes_parse_SignalMatrix(SignalMatrix<std::complex > const *__pyx_v_m) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error: command '/usr/bin/g++' failed with exit code 1
citysu
