# DataFrame.fillNa

danfo.DataFrame.fillNa(values, options) \[[source](https://github.com/opensource9ja/danfojs/blob/3398c2f540c16ac95599a05b6f2db4eff8a258c9/danfojs/src/core/frame.js#L1235)]

| Parameters | Type            | Description                                                                                                                                                                                                                   | Default          |
| ---------- | --------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------- |
| values     | Array \| Scalar | The list of value(s) to use for replacement.                                                                                                                                                                                  |                  |
| options    | Object          | <p>{<strong>columns</strong>:Array of column name(s) to fill. If undefined fill all columns</p><p><strong>inplace</strong>: Boolean indicating whether to perform the operation inplace or not. Defaults to false</p><p>}</p> | {inplace: false} |

## **Examples**

### Fill missing values in specified columns with specified values

Missing values are NaN, undefined or null values

{% tabs %}
{% tab title="Node" %}

```javascript
const dfd = require("danfojs-node")

let data = {
    "Name": ["Apples", "Mango", "Banana", undefined],
    "Count": [NaN, 5, NaN, 10],
    "Price": [200, 300, 40, 250]
}

let df = new dfd.DataFrame(data)
df.print()

let values = ["Apples", df["Count"].mean()]
let df_filled = df.fillNa(values, { columns: ["Name", "Count"] })
df_filled.print()
```

{% endtab %}

{% tab title="Browser" %}

```
```

{% endtab %}
{% endtabs %}

{% tabs %}
{% tab title="Output" %}

```
╔════════════╤═══════════════════╤═══════════════════╤═══════════════════╗
║            │ Name              │ Count             │ Price             ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 0          │ Apples            │ NaN               │ 200               ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 1          │ Mango             │ 5                 │ 300               ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 2          │ Banana            │ NaN               │ 40                ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 3          │ undefined         │ 10                │ 250               ║
╚════════════╧═══════════════════╧═══════════════════╧═══════════════════╝

╔════════════╤═══════════════════╤═══════════════════╤═══════════════════╗
║            │ Name              │ Count             │ Price             ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 0          │ Apples            │ 7.5               │ 200               ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 1          │ Mango             │ 5                 │ 300               ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 2          │ Banana            │ 7.5               │ 40                ║
╟────────────┼───────────────────┼───────────────────┼───────────────────╢
║ 3          │ Apples            │ 10                │ 250               ║
╚════════════╧═══════════════════╧═══════════════════╧═══════════════════╝
```

{% endtab %}
{% endtabs %}

### Fill all columns with NaNs with a specified value

{% tabs %}
{% tab title="Node" %}

```javascript
const dfd = require("danfojs-node")

let data = {
    "Name": ["Apples", "Mango", "Banana", undefined],
    "Count": [NaN, 5, NaN, 10],
    "Price": [200, 300, 40, 250]
}

let df = new dfd.DataFrame(data)
let df_filled = df.fillNa("Apples")

df_filled.print()
```

{% endtab %}

{% tab title="Browser" %}

```
```

{% endtab %}
{% endtabs %}

{% tabs %}
{% tab title="Output" %}

```
╔═══╤═══════════════════╤═══════════════════╤═══════════════════╗
║   │ Name              │ Count             │ Price             ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 0 │ Apples            │ Apples            │ 200               ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 1 │ Mango             │ 5                 │ 300               ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 2 │ Banana            │ Apples            │ 40                ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 3 │ Apples            │ 10                │ 250               ║
╚═══╧═══════════════════╧═══════════════════╧═══════════════════╝
```

{% endtab %}
{% endtabs %}

### Fill NaNs inplace

{% tabs %}
{% tab title="Node" %}

```javascript
const dfd = require("danfojs-node")
let data = {
    "Name": ["Apples", "Mango", "Banana", undefined],
    "Count": [NaN, 5, NaN, 10],
    "Price": [200, 300, 40, 250]
}

let df = new dfd.DataFrame(data)
let values = ["Apples", df["Count"].mean()]
df.fillNa(values, {
    columns: ["Name", "Count"],
    inplace: true
})
df.print()
```

{% endtab %}

{% tab title="Browser" %}

```
```

{% endtab %}
{% endtabs %}

{% tabs %}
{% tab title="Output" %}

```
╔═══╤═══════════════════╤═══════════════════╤═══════════════════╗
║   │ Name              │ Count             │ Price             ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 0 │ Apples            │ Apples            │ 200               ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 1 │ Mango             │ 5                 │ 300               ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 2 │ Banana            │ Apples            │ 40                ║
╟───┼───────────────────┼───────────────────┼───────────────────╢
║ 3 │ Apples            │ 10                │ 250               ║
╚═══╧═══════════════════╧═══════════════════╧═══════════════════╝
```

{% endtab %}
{% endtabs %}


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