Questions tagged [one-hot-encoding]

One-Hot Encoding is a method to encode categorical variables to numerical data that Machine Learning algorithms can deal with. One-Hot encoding is most used during feature engineering for a ML Model. It converts categorical values into a new categorical column and assign a binary value of 1 or 0 to those columns.

Also known as Dummy Encoding, One-Hot Encoding is a method to encode categorical variables, where no such ordinal relationship exists, to numerical data that Machine Learning algorithms can deal with. One hot encoding is the most widespread approach, and it works very well unless your categorical variable takes on a large number of unique values. One hot encoding creates new, binary columns, indicating the presence of each possible value from the original data. These columns store ones and zeros for each row, indicating the categorical value of that row.

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One Hot Encoding of large dataset

I want to build recommendation system using association rules with implemented in mlxtend library apriori algorithm. In my sales data there is information about 36 millions of transactions and 50k unique products. I tried to use sklearn…
psowa001
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'OneHotEncoder' object has no attribute 'transform'

I am using Spark v3.0.0. My dataframe is: indexer.show() +------+--------+-----+ |row_id| city|index| +------+--------+-----+ | 0|New York| 0.0| | 1| Moscow| 3.0| | 2| Beijing| 1.0| | 3|New York| 0.0| | 4| Paris| …
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One-Hot Encode numpy array with >2 dims

I have a numpy array of shape (192, 224, 192, 1). The last dimension is the integer class that I would like to one hot encode. For example, if I have 12 classes I would like the of the resulting array to be (192, 224, 192, 12), with the last…
PDPDPDPD
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one-hot-encoding (dummy variables) with BigQuery

I would like to use BigQuery instead of Pandas to create dummy variables (one-hot-encoding) for my categories. I will end up with about 200 columns, therefore I can't do it manually and hard code it Test dataset (the actual one has many more…
Alex
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OneHotEncoder gives ValueError : Input contains NaN ; even though my DataFrame doesn't contain any NaN as indicated by df.isna()

I am working on the titanic dataset and when trying to apply OneHotEncoding on one of the columns called 'Embarked' which has 3 possible values 'S','Q' and 'C'. It gives me the ValueError: Input contains NaN I checked the contents of the column by…
BURNS
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Multi-label classification or multi class classification or sequence labelling problem?

I have some images which look like this one: They exist of 4 possible characters (A-D) and a length of 4. Now, I would like to run a neural network, which recognizes each character in the picture. Is this a multi-label (I think so) or a multi-class…
Tobitor
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How to convert strings in a Pandas Dataframe to a list or an array of characters?

I have a dataframe called data, a column of which contains strings. I want to extract the characters from the strings because my goal is to one-hot encode them and make the usable for classification. The column containing the strings is stored in…
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OneHotEncoder from sklearn gives a ValueError when passing categories

I have an array of class names: classes = np.array(['A', 'B']) And I have an array of data (but this data only contains instances of one class): vals = np.array(['A', 'A', 'A']) vals = vals.reshape(len(vals), 1) I want to end up with one-hot…
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How to one-hot-encode matrix of sentences at the character level?

There is a dataframe: 0 1 2 3 0 a c e NaN 1 b d NaN NaN 2 b c NaN NaN 3 a b c d 4 a b NaN NaN 5 b c NaN NaN 6 a b NaN NaN 7 a b c e 8 a b c NaN 9 a c e NaN I would like…
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event start-end into hot encoding in python

I have a pandas dataframe with 2 columns "type" and "sign" as follows type sign 0 open A 1 open B 2 open D 3 close B 4 close D 5 open B 6 close B 7 close A "A" + "open" means that event A has started…
Guy Barash
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Parameter of OneHotEncoder : Categories

I have been coding on ML via Scikit-learn from few months. but a update has came on scikit object of preprocessing which is OneHotEncoder. here was a parameter categorical_features which is now changed to categories and now i am not understanding…
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Fast way for One Hot Encoding with python

In my project, I need to make oneHotEncode for millions of DNA sequences for ~100 time(in total, billions of times of similar sequences). So an effiect way will be very improtant for me. Bellow is my code, which takes 4.5s for 10K sequences. import…
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How to reverse One-Hot Encoding of labels for evaluation of ML/DL model?

This issue has been mentioned a few times here on Stackoverflow, but none provided the solution for the problem/error I'm currently facing. Currently my y of the dataset that I use as labels had to be transformed using One-Hot Encoding so that my…
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Pandas, reverse one hot encoding

I one hot encoded some variable and after some computation I would like to retrieve the original one. What I am doing is the following: I filter the one hot encoded column names (they all start with the name of the original variable, let say…
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Can PCA be applied on One-Hot-Encoded data?

I'm completely new to the concept of PCA. From what I comprehend, PCA uses sum of squares method. With that said, I Came across a one-hot-encoded data (which means im dealing with categorical data).Can PCA be applied here? If yes, would it yield…