Coding Ref

The `nunique()`

function in Pandas is used to compute the number of unique values in a dataframe or series. This can be useful for getting an overview of the data, or for identifying and removing duplicate values.

Here's an example of using the `nunique()`

function in Pandas to compute the number of unique values in a dataframe:

main.py

```
import pandas as pd
# create a sample dataframe
df = pd.DataFrame({"A": [1, 2, 3, 2, 3],
"B": [6, 7, 7, 8, 8]})
# compute the number of unique values in each column
df_nunique = df.nunique()
# display the result
print(df_nunique)
```

This will compute the number of unique values in each column of the dataframe, and return a new Series with the number of unique values in each column.

The output will be:

output

```
A 3
B 3
dtype: int64
```

You can also use the `nunique()`

function to compute the number of unique values in a particular column or row of a dataframe. For example:

main.py

```
# compute the number of unique values in the A column
col_a_nunique = df["A"].nunique()
# display the result
print(col_a_nunique)
```

This will compute the number of unique values in the `A`

column of the dataframe, and return a single integer value.

The output will be:

output

```
3
```

The `nunique()`

function is useful for computing the number of unique values in a dataframe or series, and it can be used to get an overview of the data or to identify and remove duplicate values.

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