An error occurs when using MLDataTable to load data

Question

I tried to create a word tagger model in Swift according to this tutorial in the latest XCode. But I cannot load data from a local file using MLDataTable. Here is my code.

let data = try MLDataTable(contentsOf:
URL(fileURLWithPath: "/path/to/data.json"))

The error is as follows.

error: Couldn't lookup symbols:
CreateML.MLDataTable.init(contentsOf: Foundation.URL, options: CreateML.MLDataTable.ParsingOptions) throws -> CreateML.MLDataTable

I tried absolute path and relative path, but neither of them worked(I am pretty sure that the data file is in the right location and the paths are correct). In addition, I can load the local file to a URL object, so the problem should lie in MLDataTable.

Could someone help?

Answer 1

I have the same error however I used .csv file. But the problem is solved when I use COREML tool under developer tools of Xcode.

Here are some recommendations:

1. Your training data's class column label should be "label"

2. Your training data can be one file but testing data should contains sub folders named exactly the same name of your label's names. To illustrate, you have "negative", "positive" and "neutral as label names. Then you should have three sub folders named "negative", "positive" and "neutral". Moreover testing data files can't be one json or csv file including all the testing data. For example if you have five rows of negative labeled data, you can't put that csv file under negative sub-folder. You have to create five txt file for each five row.