static void Main(string[] args)
{
//Read in csv file(s) or a .dprep package.
string FMInfoPath = Path.Combine(Directory.GetCurrentDirectory(), "farmers-markets-info.csv");
string FMProductsPath = Path.Combine(Directory.GetCurrentDirectory(), "farmers-markets-products.csv");
string resultPath = Path.Combine(Directory.GetCurrentDirectory(), "result.csv");
DataFlow dataFlowMarketInfo = Reader.AutoReadFile(FMInfoPath);
DataFlow dataFlowProducts = Reader.AutoReadFile(FMProductsPath);
//Select useful columns.
dataFlowMarketInfo = dataFlowMarketInfo.KeepColumns(
columnNames: new string[] { "FMID", "MarketName", "State", "zip", "Location" });
dataFlowProducts = dataFlowProducts.KeepColumns(
columnNames: new string[] { "Credit", "Organic", "Flowers" });
//Column type conversions: ToBool, ToLong, ToNumber, ToString, ToDateTime.
dataFlowMarketInfo = dataFlowMarketInfo.ToString(columnName: "FMID");
dataFlowProducts = dataFlowProducts.ToBool(
columnName: "Organic",
trueValues: new List <string> {
"Y"
},
falseValues: new List <string> {
"N"
},
mismatchAs: MismatchAsOption.AsFalse);
//Replace values to null values.
dataFlowMarketInfo = dataFlowMarketInfo.ReplaceNa(
columnName: "Location",
customNaList: "Other");
dataFlowMarketInfo = dataFlowMarketInfo.ReplaceNa(columnName: "zip");
//Append columns from one dataflow to the other.
DataFlow dataFlowCombined = dataFlowMarketInfo.AppendColumns(
dataflows: new List <DataFlow> {
dataFlowProducts
});
//Sort values in selected column.
List <Tuple <string, bool> > sortOrder = new List <Tuple <string, bool> >
{
new Tuple <string, bool>("State", false)
};
dataFlowCombined = dataFlowCombined.Sort(sortOrder);
//Write output to a csv file or save to .dprep package.
DataFlow result = dataFlowCombined.WriteDelimitedFile(resultPath);
// Get a IDataView object for further model training, such as ML.Net
IDataView dataView = result.ToDataView();
}