complete cython interface, python example usage.py

cython/py_tdm_reaper.pyx

@@ -1,7 +1,8 @@
 # distutils: language = c++
 
 from tdm_reaper cimport tdm_reaper
-# import numpy as np
+import json as jsn
+import numpy as np
 # import re
 # import os
 
@@ -14,6 +15,26 @@ cdef class tdmreaper:
   def __cinit__(self, string tdmfile, string tdxfile):
     self.cpp_tdm = tdm_reaper(tdmfile,tdxfile)
 
+  # provide TDM files
+  def submit_files(self,string tdmfile, string tdxfile):
+    self.cpp_tdm.submit_files(tdmfile,tdxfile)
+
+  # get list of channel(-group) ids
+  def get_channelgroup_ids(self):
+    return self.cpp_tdm.get_channelgroup_ids()
+  def get_channel_ids(self):
+    return self.cpp_tdm.get_channel_ids()
+
+  # get data of specific channel
+  def get_channel(self, string id):
+    return self.cpp_tdm.get_channel_as_double(id)
+
+  # get meta-data of channel(-group)
+  def get_channelgroup_info(self, string id):
+    return self.cpp_tdm.get_channelgroup_info(id)
+  def get_channel_info(self, string id):
+    return self.cpp_tdm.get_channel_info(id)
+
   # def set_file(self, string rawfile):
   #   if not os.path.isfile(rawfile) :
   #     raise ValueError("'" + str(rawfile) + "' does not exist")

cython/tdm_reaper.pxd

@@ -2,8 +2,8 @@
 
 # use some C++ STL libraries
 from libcpp.string cimport string
-# from libcpp.vector cimport vector
-# from libcpp cimport bool
+from libcpp.vector cimport vector
+from libcpp cimport bool
 
 cdef extern from "tdm_reaper.cpp":
   pass
@@ -13,7 +13,17 @@ cdef extern from "tdm_reaper.hpp":
     # constructor(s)
     tdm_reaper() except +
     tdm_reaper(string tdmfile, string tdxfile) except +
-        # set new file for decoding
+    # provide TDM files
+    void submit_files(string tdmfile, string tdxfile) except+
+    # get list of channel(-group) ids
+    vector[string] get_channelgroup_ids() except+
+    vector[string] get_channel_ids() except+
+    # get data of specific channel
+    vector[double] get_channel_as_double(string id) except+
+    # get meta-data
+    string get_channelgroup_info(string id) except+
+    string get_channel_info(string id) except+
+
         # void set_file(string)
         # # perform conversion (pass any C++ exceptions to Python)
         # void setup_and_conversion() except +

lib/tdm_datamodel.hpp

@@ -160,6 +160,17 @@ struct tdm_channelgroup {
     return formatter.get_info();
   }
 
+  const std::string get_json()
+  {
+    std::stringstream ss;
+    ss<<"{"<<"\"group-id\":\""<<id_
+           <<"\",\"name\":\""<<name_
+           <<"\",\"description\":\""<<description_
+           <<"\",\"root\":\""<<root_
+           <<"\",\"channels\":\""<<join_strings(channels_)<<"\"}";
+    return ss.str();
+  }
+
 };
 
 // -------------------------------------------------------------------------- //
@@ -216,6 +227,20 @@ struct tdm_channel {
     return formatter.get_info();
   }
 
+  const std::string get_json()
+  {
+    std::stringstream ss;
+    ss<<"{"<<"\"channel-id\":\""<<id_
+           <<"\",\"name\":\""<<name_
+           <<"\",\"description\":\""<<description_
+           <<"\",\"unit_string\":\""<<unit_string_
+           <<"\",\"datatype\":\""<<datatype_
+           <<"\",\"minimum\":\""<<minimum_
+           <<"\",\"maximum\":\""<<maximum_
+           <<"\",\"group\":\""<<group_<<"\"}";
+    return ss.str();
+  }
+
 };
 
 // -------------------------------------------------------------------------- //

lib/tdm_datatype.hpp

@@ -104,6 +104,20 @@ public:
     return *this;
   }
 
+  // obtain number as double
+  double as_double()
+  {
+    double num;
+    if ( dtidx_ == 0 ) num = (double)sint16_;
+    else if ( dtidx_ == 1 ) num = (double)sint32_;
+    else if ( dtidx_ == 2 ) num = (double)uint8_;
+    else if ( dtidx_ == 3 ) num = (double)uint16_;
+    else if ( dtidx_ == 4 ) num = (double)uint32_;
+    else if ( dtidx_ == 5 ) num = (double)float32_;
+    else if ( dtidx_ == 6 ) num = (double)float64_;
+    return num;
+  }
+
   // define custom stream operator to print the correct type
   friend std::ostream& operator<<(std::ostream& out, const tdmdatatype& num)
   {

lib/tdm_reaper.hpp

@@ -177,6 +177,34 @@ public:
   // extract channel by id
   std::vector<tdmdatatype> get_channel(std::string& id);
 
+  // additional methods for Cython/Python compatibiliy
+  //
+  // extract and return any channel as datatype double
+  std::vector<double> get_channel_as_double(std::string id)
+  {
+    std::vector<tdmdatatype> tdmchn = this->get_channel(id);
+    std::vector<double> chn;
+    for ( tdmdatatype el: tdmchn ) chn.push_back(el.as_double());
+    return chn;
+  }
+  // get channel(-group) meta-data
+  std::string get_channelgroup_info(std::string id)
+  {
+    if ( tdmchannelgroups_.count(id) == 1 ) {
+      return tdmchannelgroups_.at(id).get_json();
+    } else {
+      throw std::runtime_error(std::string("channelgroup does not exist: ") + id);
+    }
+  }
+  std::string get_channel_info(std::string id)
+  {
+    if ( tdmchannels_.count(id) == 1 ) {
+      return tdmchannels_.at(id).get_json();
+    } else {
+      throw std::runtime_error(std::string("channel does not exist: ") + id);
+    }
+  }
+
   // dump a single channel/entire group (identified by id) to file
   void print_channel(std::string &id, const char* filename, bool include_meta = true);
   void print_group(std::string &id, const char* filename, bool include_meta = true, char sep = ' ');

makefile

@@ -79,13 +79,14 @@ cython-list : cython/setup.py
 
 cython-build : cython/setup.py cython/tdm_reaper.pxd cython/py_tdm_reaper.pyx $(HPP) lib/tdm_reaper.cpp
 	python3 $< build_ext --inplace
-	# python3 $< build_ext
+	cp -v tdm_reaper.cpython-*.so python/
 
 cython-install : cython/setup.py cython/tdm_reaper.pyx cython/tdm_reaper.pyx
 	python3 $< install
 
 clean-cython :
-	rm -vf cython/py_tdm_reaper.cpp tdm_reaper.cpython-*.so
+	rm -vf cython/py_tdm_reaper.cpp
+	rm -vf tdm_reaper.cpython-*.so python/tdm_reaper.cpython-*.so
 	rm -rf build
 
 # --------------------------------------------------------------------------- #

python/usage.py

@@ -0,0 +1,40 @@
+
+import tdm_reaper
+import numpy as np
+import json
+
+# create 'tdm_reaper' instance object
+try :
+    jack = tdm_reaper.tdmreaper(b'samples/SineData.tdm',b'samples/SineData.tdx')
+except RuntimeError as e:
+    print("failed to load/decode TDM files: " + str(e))
+
+# list ids of channelgroups
+grpids = jack.get_channelgroup_ids()
+grpids = [x.decode() for x in grpids]
+print("list of channelgroups: ",grpids)
+
+# obtain meta data of channelgroups
+for grp in grpids[0:2] :
+    grpinfostr = jack.get_channelgroup_info(grp.encode())
+    grpinfostr = grpinfostr.decode()
+    grpinfo = json.loads(grpinfostr)
+    print( json.dumps(grpinfo,sort_keys=False,indent=4) )
+
+# list ids of channels
+chnids = jack.get_channel_ids()
+chnids = [x.decode() for x in chnids]
+print("list of channels: ",chnids)
+
+# get (meta-)data of channels
+for chn in chnids[0:3] :
+
+    # obtain meta-data
+    chninfostr = jack.get_channel_info(chn.encode())
+    chninfostr = chninfostr.decode()
+    chninfo = json.loads(chninfostr)
+    print( json.dumps(chninfo,sort_keys=False,indent=4) )
+
+    # channel data
+    chndata = jack.get_channel(chn.encode())
+    print(str(chndata[0:6]) + " ...")