Using Scipy’s zscore function:
df = pd.DataFrame(np.random.randint(100, 200, size=(5, 3)), columns=['A', 'B', 'C'])
df
| | A | B | C |
|---:|----:|----:|----:|
| 0 | 163 | 163 | 159 |
| 1 | 120 | 153 | 181 |
| 2 | 130 | 199 | 108 |
| 3 | 108 | 188 | 157 |
| 4 | 109 | 171 | 119 |
from scipy.stats import zscore
df.apply(zscore)
| | A | B | C |
|---:|----------:|----------:|----------:|
| 0 | 1.83447 | -0.708023 | 0.523362 |
| 1 | -0.297482 | -1.30804 | 1.3342 |
| 2 | 0.198321 | 1.45205 | -1.35632 |
| 3 | -0.892446 | 0.792025 | 0.449649 |
| 4 | -0.842866 | -0.228007 | -0.950897 |
If not all the columns of your data frame are numeric, then you can apply the Z-score function only to the numeric columns using the select_dtypes
function:
# Note that `select_dtypes` returns a data frame. We are selecting only the columns
numeric_cols = df.select_dtypes(include=[np.number]).columns
df[numeric_cols].apply(zscore)
| | A | B | C |
|---:|----------:|----------:|----------:|
| 0 | 1.83447 | -0.708023 | 0.523362 |
| 1 | -0.297482 | -1.30804 | 1.3342 |
| 2 | 0.198321 | 1.45205 | -1.35632 |
| 3 | -0.892446 | 0.792025 | 0.449649 |
| 4 | -0.842866 | -0.228007 | -0.950897 |