# re() Function & Examples

Use the re() complex function in Calcul.io. Review its syntax, edit working examples, understand the result, and explore related math functions.

## re

#### re(x)

Try it yourself:

```calculio
re(2 + 3i)
im(2 + 3i)
re(-5.2i)
re(2.4)
```

[im](https://calcul.io/function/im/index.md)

[conj](https://calcul.io/function/conj/index.md)

[abs](https://calcul.io/function/abs/index.md)

[arg](https://calcul.io/function/arg/index.md)

---

## re(): Real Part of a Complex Value

**re()** extracts the real component of a complex number. For 3 + 4i, re returns 3. This is useful for signals, phasors, and separating Cartesian components.

## Complex components

Use [im()](https://calcul.io/function/im/index.md) for the imaginary component, [abs()](https://calcul.io/function/abs/index.md) for magnitude, and [arg()](https://calcul.io/function/arg/index.md) for phase. For a real input, re simply returns the input.

Do not confuse real-part extraction with rounding or type conversion. Preserve both components until the model explicitly calls for a real projection; dropping the imaginary part can change the meaning of a calculation.

[All functions](https://calcul.io/functions/index.md)