From a7633e89dee012102a041be8f2a81329e2f32b1f Mon Sep 17 00:00:00 2001
From: xieguigang <xie.guigang@gcmodeller.org>
Date: Sat, 19 Jun 2021 13:47:45 +0800
Subject: [PATCH] cdf data driver

---
 LINQ/Drivers/NetCDF/CDFDataSet.vb | 127 +++++++++++++++++++++---------
 1 file changed, 88 insertions(+), 39 deletions(-)

diff --git a/LINQ/Drivers/NetCDF/CDFDataSet.vb b/LINQ/Drivers/NetCDF/CDFDataSet.vb
index fdc4c49..5ed9636 100644
--- a/LINQ/Drivers/NetCDF/CDFDataSet.vb
+++ b/LINQ/Drivers/NetCDF/CDFDataSet.vb
@@ -1,56 +1,105 @@
 #Region "Microsoft.VisualBasic::6b9b62435842858d057df49f23e18377, LINQ\Drivers\NetCDF\CDFDataSet.vb"
 
-    ' Author:
-    ' 
-    '       asuka (amethyst.asuka@gcmodeller.org)
-    '       xie (genetics@smrucc.org)
-    '       xieguigang (xie.guigang@live.com)
-    ' 
-    ' Copyright (c) 2018 GPL3 Licensed
-    ' 
-    ' 
-    ' GNU GENERAL PUBLIC LICENSE (GPL3)
-    ' 
-    ' 
-    ' This program is free software: you can redistribute it and/or modify
-    ' it under the terms of the GNU General Public License as published by
-    ' the Free Software Foundation, either version 3 of the License, or
-    ' (at your option) any later version.
-    ' 
-    ' This program is distributed in the hope that it will be useful,
-    ' but WITHOUT ANY WARRANTY; without even the implied warranty of
-    ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    ' GNU General Public License for more details.
-    ' 
-    ' You should have received a copy of the GNU General Public License
-    ' along with this program. If not, see <http://www.gnu.org/licenses/>.
-
-
-
-    ' /********************************************************************************/
-
-    ' Summaries:
-
-    ' Class CDFDataSet
-    ' 
-    '     Constructor: (+1 Overloads) Sub New
-    '     Function: ReadFromUri
-    ' 
-    ' /********************************************************************************/
+' Author:
+' 
+'       asuka (amethyst.asuka@gcmodeller.org)
+'       xie (genetics@smrucc.org)
+'       xieguigang (xie.guigang@live.com)
+' 
+' Copyright (c) 2018 GPL3 Licensed
+' 
+' 
+' GNU GENERAL PUBLIC LICENSE (GPL3)
+' 
+' 
+' This program is free software: you can redistribute it and/or modify
+' it under the terms of the GNU General Public License as published by
+' the Free Software Foundation, either version 3 of the License, or
+' (at your option) any later version.
+' 
+' This program is distributed in the hope that it will be useful,
+' but WITHOUT ANY WARRANTY; without even the implied warranty of
+' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+' GNU General Public License for more details.
+' 
+' You should have received a copy of the GNU General Public License
+' along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+
+
+' /********************************************************************************/
+
+' Summaries:
+
+' Class CDFDataSet
+' 
+'     Constructor: (+1 Overloads) Sub New
+'     Function: ReadFromUri
+' 
+' /********************************************************************************/
 
 #End Region
 
 Imports LINQ.Runtime.Drivers
+Imports Microsoft.VisualBasic.ComponentModel.DataSourceModel
+Imports Microsoft.VisualBasic.Data.IO.netCDF
+Imports Microsoft.VisualBasic.Language
+Imports Microsoft.VisualBasic.My.JavaScript
 
 <DriverFlag("dataframe")>
 Public Class CDFDataSet : Inherits DataSourceDriver
 
+    ''' <summary>
+    ''' 
+    ''' </summary>
+    ''' <param name="arguments">should be variable name</param>
     Public Sub New(arguments() As String)
         MyBase.New(arguments)
     End Sub
 
-    Public Overrides Function ReadFromUri(uri As String) As IEnumerable(Of Object)
-        Throw New NotImplementedException()
+    Public Overrides Iterator Function ReadFromUri(uri As String) As IEnumerable(Of Object)
+        Using cdf As New netCDFReader(uri)
+            Dim vectors As New List(Of NamedValue(Of Func(Of Integer, Object)))
+            Dim size As Integer
+
+            For Each name As String In arguments
+                vectors += New NamedValue(Of Func(Of Integer, Object)) With {
+                    .Name = name,
+                    .Value = vectorReader(cdf, name, size),
+                    .Description = size
+                }
+            Next
+
+            Dim maxSize As Integer = vectors _
+                .Select(Function(v)
+                            Return Integer.Parse(v.Description)
+                        End Function) _
+                .Max
+
+            For i As Integer = 0 To maxSize - 1
+                Dim obj As New JavaScriptObject
+
+                For Each field In vectors
+                    obj(field.Name) = field.Value(i)
+                Next
+
+                Yield obj
+            Next
+        End Using
+    End Function
+
+    Private Shared Function vectorReader(cdf As netCDFReader, name As String, ByRef size As Integer) As Func(Of Integer, Object)
+        Dim vec As Array = cdf.getDataVariable(name).genericValue
+
+        size = vec.Length
+
+        If size = 1 Then
+            Dim [single] As Object = vec.GetValue(Scan0)
+
+            Return Function(i) [single]
+        Else
+            Return AddressOf vec.GetValue
+        End If
     End Function
 End Class