read/write of the r# dataframe in binary file format

Author: xieguigang

R#/Runtime/Internal/internalInvokes/file.vb

@@ -122,6 +122,11 @@ Namespace Runtime.Internal.Invokes
     <Package("file")>
     Public Module file
 
+        Sub New()
+            Call generic.add("writeBin", GetType(dataframe), AddressOf writeBinDataframe)
+            Call generic.add("readBin.dataframe", GetType(Stream), AddressOf readBinDataframe)
+        End Sub
+
         ''' <summary>
         ''' # Generate SHA1 checksum of a file
         ''' </summary>
@@ -1512,6 +1517,24 @@ Namespace Runtime.Internal.Invokes
             Return out
         End Function
 
+        <RGenericOverloads("writeBin")>
+        Private Function writeBinDataframe(dataframe As dataframe, args As list, env As Environment) As Object
+            Dim con As Stream = args!con
+            Dim buffer As New dataframeBuffer(dataframe, env)
+
+            Call buffer.Serialize(con)
+            Call con.Flush()
+
+            Return True
+        End Function
+
+        <RGenericOverloads("readBin.dataframe")>
+        Private Function readBinDataframe(s As Stream, args As list, env As Environment) As Object
+            Dim buffer As New dataframeBuffer(s)
+            Dim df As dataframe = buffer.getFrame
+            Return df
+        End Function
+
         ''' <summary>
         ''' close connections, i.e., “generalized files”, such as possibly compressed files, URLs, pipes, etc.
         ''' </summary>

R#/Runtime/Serialize/bufferObjects/dataframeBuffer.vb

@@ -93,6 +93,10 @@ Namespace Runtime.Serialize
             Call MyBase.New(data)
         End Sub
 
+        ''' <summary>
+        ''' write dataframe value to binary file
+        ''' </summary>
+        ''' <param name="buffer"></param>
         Public Overrides Sub Serialize(buffer As Stream)
             Dim colnames As String() = dataframe.colnames
             Dim rownames As String() = dataframe.getRowNames