Tabular data with multiple outputs

Part 1 (2019) Advanced (Part 1 v3)
1

Hello.
I’m fooling around with the tabular data and gets some errors when trying to create a datablock with two columns as ‘y’.
I get the error: 'got an unexpected keyword argument ‘one_hot’

# Create dataframe
df=pd.DataFrame()
df['A']=np.arange(datalen)
df['B']=np.arange(datalen)*10
df['C']=np.arange(datalen)*100
df['D']=np.random.choice(a=[True,False], size=datalen)
df['out']=np.arange(datalen)*2
df['out2'] =np.arange(datalen)*2
# create datablock
 start = int(0.8 * len(df))
 idx = list(range(start, len(df)))
 procs = [Categorify]

 src = (TabularList.from_df(df, cat_names=['D'], cont_names=['A', 'B', 'C'], procs=procs)
               .split_by_idx(idx)
               .label_from_df(cols=['out', 'out2'], label_cls=FloatList, log=True)
               .databunch(bs=8))

I’ve tracked down the error to the function: label_from_df in data_block.py

Could it be that this function should look like this instead?

def label_from_df(self, cols:IntsOrStrs=1, **kwargs):
        "Label `self.items` from the values in `cols` in `self.xtra`."
        labels = _maybe_squeeze(self.xtra.iloc[:,df_names_to_idx(cols, self.xtra)])
        assert labels.isna().sum().sum() == 0, f"You have NaN values in column(s) {cols} of your dataframe, please fix it." 
# Added check for 'log', If this key is in kwargs, the y should not be one-hot encoded 
# using multi category
        if is_listy(cols) and len(cols) > 1 and not 'log' in kwargs:
            new_kwargs = dict(one_hot=True, label_cls=MultiCategoryList, classes= cols)
# swithced place on kwargs and new_kwargs since "MultyCategoryList should override
# existing "FloatList". FloatList don't take the 'one hot' key.
           # org kwargs = {**new_kwargs, **kwargs}
            kwargs = {**kwargs, **new_kwargs}
        return self.label_from_list(labels, **kwargs)
3 Likes
2

You can have multiple Columns only for one-hot encoded values - check the source for label_from_df(…)

If you want to predict a Tuple you should create a custom ItemBase - see:

https://docs.fast.ai/tutorial.itemlist.html#Example:-ImageTuple

But on Y instead of X.

3

I can’t have multiple columns for one-hot encoded values because of the bug mentioned above. **kwargs and **new_kwargs are in wrong order which means that MultiCategoryList cls is never called.

Thanks for the link of the documentation, but I tested the code that I wrote above and it seems to work just fine to iterate over the data. I have not yet tested with tabular learners, since I’m trying to write my own custom one. Maybe I have missed some details that does not work properly?

4

Did you figure out how to do this @dangraf ? I’d also like to predict multiple outputs.

5

@dangraf @austeane I’m interested if either of you have made any progress on this as well.

6

Hello. I switched tasks so I didn’t dig deeper into this. I will do it later this year but now it’s on hold.