| This post was kindly contributed by SAS from Out in Left Field - go there to comment and to read the full post. |
I have been spending the last week working on how the interface to the sas dataset can be used by a .NET developer. It is of particular concern because once the initial dll is released, it will be hard to change it. Getting the interface ‘mostly’ correct is important.
After a lot of thought, here is what I have so far:
//Initiate logging
Savian.SaviDataSet.Logging.StartLog(@”c:\temp\SaviDataSetErrors.log”);
//Create SAS dataset object
SasDataSet ds = new SasDataSet();
//Add 4 variables
ds.AddVariable(“AA1”, “Var1”);
ds.AddVariable(“AA2”, “Var2”);
ds.AddVariable(“AA3”, “Var3″, 10, SasVariableType.Character,”$5.”,”$7.”);
ds.AddVariable(“AA4”, “Var4”, 10, SasVariableType.Character);
//Add observations
//Bulk insertion
for (int i = 0; i < 1000; i++)
{
object[] values = new object[] {1, 2, “Test_” + (i + 1).ToString(“00#”), “Test2”, “Test3”, “Test4”, “Test5”};
ds.AddObservation(i, values );
}
//Modify observation – Similar to a .NET dataset
ds.Observations[0][“AA1”].Value = “Test”;
//Write dataset
ds.WriteDataSet(“TEMP”, @”c:\temp\test.sas7bdat”);
//Stop logging
Savian.SaviDataSet.Logging.CloseLog();
The area that was a challenge was adding observations since they are really an array across existing variable metadata.
The other area I am focused on is keeping the wording the same as how SAS would refer to things. Hence, observation instead of row and variable instead of column.
I have also been working on validation so that invalid data does not make it into the dataset. I can’t prevent everything, but I am making a good faith effort to minimize it. Also, formats/informats have to be checked, name lengths, length values, dataset name, etc. all have to be verified to make sure they comply. So far, so good but more checking is underway.
While working on this, you realize how much effort has been put into the dataset by SAS over the years and how much work they have to go through to make things compliant and workable.
| This post was kindly contributed by SAS from Out in Left Field - go there to comment and to read the full post. |