Changes between Version 1 and Version 2 of CSMLReadMethods

Timestamp:

24/07/06 15:02:08 (13 years ago)

Author:

domlowe

Comment:

More edits to how to

CSMLReadMethods

@@ -4 +4 @@
 
 The basic read methods that need implementing for a new data format are:
-
+ * DI.openFile(self, fileName) --- opens the file
  * DI.setAxis(self,axisName)    --- this 'sets' the axis you want to read (axis: e.g latitude, time, pressure, depth.. etc)
  * DI.getDataForAxis(self) --- this returns the entire set of values for that axis
- * DI.setVariable(self,variableName) --- this 'sets' the variable you want to read (variable: e.g Temperature, WindSpeed etc..)
+ * DI.setVariable(self,variableName) --- this 'sets' the variable you want to read (variable: e.g Temperature, !WindSpeed etc..)
  * DI.getDataForVariable(self,) --- this returns the entire set of values for that variable
  * DI.getSubsetOfDataForVar(self,**kwargs) --- this returns a subset of values for that variable 
+ * DI.closeFile(self) --- closes the open file
+
+
+When the CSML API instantiates a !DataInterface object (from now on, DI), what is actually returned is a data interface specific to the data format.
+
+In the !DataInterface class there is a bit of python code that does something like this:
+
+{{{
+#!python
+                if self.iface == 'nappy':
+                        return NappyInterface()
+                elif self.iface == 'cdunif':
+                        return cdunifInterface()
+}}}
 
 
 
-As an example
+So if you want to integrate your format, XYZFormat, the first thing to do is to create an XYZInterface() and we can then have:
+{{{
+#!python
+                if self.iface == 'nappy':
+                        return NappyInterface()
+                elif self.iface == 'cdunif':
+                        return cdunifInterface()
+                elif self.iface == 'XYZ':
+                        return XYZInterface()
+
+}}}
+
+
+
+
+
+So (in python) you should create a class that looks like this:
+
+{{{
+#!python
+class XYZInterface(AbstractDI):
+    #Data Interface for XYZ File format
+
+    def __init__(self):
+        #this might change when CSML is revamped
+        self.extractType='XYZExtract'
+        self.extractPrefix = '_XYZextract_'
+
+    def openFile(self, filename):
+        #some code to open the file
+
+    def setAxis(self,axis):
+        #some code to set an axis to be queried, may not need to do much, depending on your format
+
+    def getDataForAxis(self):
+        #some code to return the values for an axis
+        return data
+
+    def setVariable(self,varname):
+        #some code to set a variable to be queried, may not need to do much, depending on your format
+
+
+    def getDataForVar(self):
+        #some code to return all values for a variable
+        return data
+
+    def getSubsetOfDataForVar(self, **kwargs):
+        #takes keyword args defining subset eg
+        #subset=getSubsetOfDataForVar(latitude=(0.,10.0), longitude=(90, 100.0), ...)
+        #and returns a subset of data for tha variable 
+        return data
+
+    def closeFile(self):
+        #some code to close the file
+}}}
+
+