pandas to categorical code example

Example 1: pandas categorical to numeric

#this will label the different catagories as 0,1,2,3....
dataset["sex"] = dataset["sex"].astype('category').cat.codes

Example 2: using df.astype to select categorical data and numerical data

df = pd.DataFrame({'vertebrates': ['Bird', 'Bird', 'Mammal', 'Fish', 'Amphibian', 'Reptile', 'Mammal']})

df.vertebrates.astype("category").cat.codes

Example 3: panda categorical data into numerica

sex = train_dataset['Sex'].replace(['female','male'],[0,1])
print(sex)

Example 4: pandas categorical to numeric

#this will label as one hot vectors (origin is split into 3 columns - USA, Europe, Japan and any one place will be 1 while the others are 0)
dataset['Origin'] = dataset['Origin'].map({1: 'USA', 2: 'Europe', 3: 'Japan'})

Example 5: using df.astype to select categorical data and numerical data

df.satisfaction.astype("category",
  ordered=True,
  categories=ordered_satisfaction
)

Example 6: how to store categorical variables in separate dataframe

df.loc[:,df.dtypes==np.object]