### New solution (using D3 v5.8)

After more than 2 years this question finally has a D3-based answer that doesn't suggest removing 0 from the domain, as I did in my original answer (see below).

This is possible due to the new Symlog scale in D3 v5.8, based on a by-symmetric log transformation, which allows 0 in the domain.

So, using your domain and range without any modification:

```
var myLogScale = d3.scaleSymlog()
.domain([0, 100])
.range([50, 1150]);
console.log(myLogScale(71));
```

`<script src="https://d3js.org/d3.v5.min.js"></script>`

Or even shorter, with the new scale constructors in D3 v5.8:

```
var myLogScale = d3.scaleSymlog([0, 100], [50, 1150]);
console.log(myLogScale(71));
```

`<script src="https://d3js.org/d3.v5.min.js"></script>`

### Original answer (for D3 v3)

Change your domain so it doesn't include or cross zero:

```
var myLogScale = d3.scale.log()
.domain([1e-6, 100])//domain doesn't include zero now
.range([50, 1150]);
console.log(myLogScale(71));
```

`<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>`

In the above demo I'm using `1e-6`

, which is `0.000001`

.

**Explanation:**

The logarithm of zero is undefined (or not defined). In base 10, for instance, log(0) is a number `x`

so that 10 raised to the power of `x`

is zero... that number, of course, doesn't exist. The limit, however, when we approach zero from the positive side is minus infinity.

In pure JavaScript:

`console.log("Log of 0 is: " + Math.log(0))`

Thus, in JavaScript, `log(0)`

is negative infinity, or minus infinity.

That being said, according to the API:

a log scale must have either an exclusively-positive or exclusively-negative domain; the domain must not **include or cross zero**. (emphasis mine)