動態構建管道鏈

Question

使用此示例中的代碼。

此代碼的工作原理：

var pipeline = mlContext.Transforms.CopyColumns(outputColumnName: "Label", inputColumnName: "FareAmount")
            .Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "VendorIdEncoded", inputColumnName: "VendorId"))
            .Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "RateCodeEncoded", inputColumnName: "RateCode"))
            .Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "PaymentTypeEncoded", inputColumnName: "PaymentType"))
            .Append(mlContext.Transforms.Concatenate("Features", "VendorIdEncoded", "RateCodeEncoded", "PassengerCount", "TripTime", "TripDistance", "PaymentTypeEncoded"))
            .Append(mlContext.Regression.Trainers.FastTree());

但我想像這樣在運行時動態追加：

var pipeline = mlContext.Transforms.CopyColumns(outputColumnName: "Label", inputColumnName: "FareAmount");
pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "VendorIdEncoded", inputColumnName: "VendorId"));
pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "RateCodeEncoded", inputColumnName: "RateCode"));
pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "PaymentTypeEncoded", inputColumnName: "PaymentType"));
pipeline.Append(mlContext.Transforms.Concatenate("Features", "VendorIdEncoded", "RateCodeEncoded", "PassengerCount", "TripTime", "TripDistance", "PaymentTypeEncoded"));
pipeline.Append(mlContext.Regression.Trainers.FastTree());

第一個命令之后的命令均無效。 如何動態鏈接附加？

嘗試時：

var pipeline = mlContext.Transforms.CopyColumns(outputColumnName: "Label", inputColumnName: "FareAmount");
pipeline = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "VendorIdEncoded", inputColumnName: "VendorId"));
pipeline = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "RateCodeEncoded", inputColumnName: "RateCode"));
pipeline = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "PaymentTypeEncoded", inputColumnName: "PaymentType"));
pipeline = pipeline.Append(mlContext.Transforms.Concatenate("Features", "VendorIdEncoded", "RateCodeEncoded", "PassengerCount", "TripTime", "TripDistance", "PaymentTypeEncoded"));
pipeline = pipeline.Append(mlContext.Regression.Trainers.FastTree());

我收到“無法將類型'Microsoft.ML.Data.EstimatorChain'隱式轉換為'Microsoft.ML.Transforms.ColumnCopyingEstimator'”錯誤

嘗試時

var pipeline = mlContext.Transforms.CopyColumns(outputColumnName: "Label", inputColumnName: "FareAmount");
var pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "VendorIdEncoded", inputColumnName: "VendorId"));
pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "RateCodeEncoded", inputColumnName: "RateCode"));
pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "PaymentTypeEncoded", inputColumnName: "PaymentType"));
var pipeline3 = pipeline2.Append(mlContext.Transforms.Concatenate("Features", "VendorIdEncoded", "RateCodeEncoded", "PassengerCount", "TripTime", "TripDistance", "PaymentTypeEncoded"));
var pipeline4 = pipeline3.Append(mlContext.Regression.Trainers.FastTree());
var model = pipeline4.Fit(dataView);

但是，在最后一行，我得到了“ System.ArgumentOutOfRangeException：'找不到輸入列'VendorIdEncoded'參數名稱：inputSchema'”錯誤

Answer 1

正如@Camilo Terevinto在評論部分中解釋的那樣，您需要將結果放入pipeline ：

var pipeline = mlContext.Transforms.CopyColumns(outputColumnName: "Label", inputColumnName: "FareAmount");
var pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "VendorIdEncoded", inputColumnName: "VendorId"));
pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "RateCodeEncoded", inputColumnName: "RateCode"));
pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "PaymentTypeEncoded", inputColumnName: "PaymentType"));
pipeline2 = pipeline.Append(mlContext.Transforms.Concatenate("Features", "VendorIdEncoded", "RateCodeEncoded", "PassengerCount", "TripTime", "TripDistance", "PaymentTypeEncoded"));
pipeline2 = pipeline.Append(mlContext.Regression.Trainers.FastTree());

最終的答案是

var pipeline = mlContext.Transforms.CopyColumns(outputColumnName: "Label", inputColumnName: "FareAmount");
var pipeline2 = pipeline.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "VendorIdEncoded", inputColumnName: "VendorId"));
pipeline2 = pipeline2.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "RateCodeEncoded", inputColumnName: "RateCode"));
pipeline2 = pipeline2.Append(mlContext.Transforms.Categorical.OneHotEncoding(outputColumnName: "PaymentTypeEncoded", inputColumnName: "PaymentType"));
var pipeline3 = pipeline2.Append(mlContext.Transforms.Concatenate("Features", "VendorIdEncoded", "RateCodeEncoded", "PassengerCount", "TripTime", "TripDistance", "PaymentTypeEncoded"));
var pipeline4 = pipeline3.Append(mlContext.Regression.Trainers.FastTree());
var model = pipeline4.Fit(dataView);