When the number is empty, its value isNaN. So one needs to test for that, like in \`isNaN(gain) ? 0 : gain\`. Wish: option to set a default for when isNaN. When typed number falls outside of range (e.g. when using Range to select item from array), result of array reference is \`undefined\`. Wish: option to ‘squeeze’ value to always be in range.

To always have correct values—automatically when ‘ranging’ an array—I now have: squeeze = (x, r) => { const range = Array.isArray(r) ? [0, r.length - 1] : r return isNaN(x) ? range[0] : x < range[0] ? range[0] : x > range[1] ? range[1] : x }

Release 0.7.13 added input validation to Range, so invalid values are no longer visible. https://github.com/observablehq/inputs/releases/tag/v0.7.13

Great! Thank you.

Setting value:NaN defaults to showing the placeholder. But gain still has a value. Is there a clearer way to show the placeholder on loading?

What about Range of dates (with custom steps, i.e. 6h or 2days or ...)? I guess with current construct there would be quite a lot of transformation and formatting if at any possible. Or does it "deserve" its own input? Any suggestions / pointers?

I think that’s outside the scope of the input, because you’re intended to be able to type into the number input to set the value. Though perhaps a date range could let you type a date in… Feel free to upvote this issue: https://github.com/observablehq/inputs/issues/38

Weirdly enough, this fails: viewof x = Range([-0.5857864376269049, 2]) Symptom: variable x never reaches -0.586, although the value displayed in the number input element does This also fails: viewof x = Range([-0.5857864376269049, 2], {step:0.0001}) Symptom: variable x is never updated, although the number input element does.

This appears to be a precision problem with the behavior of native inputs. I would suggest not relying on such high precision for user input. For example, an extent of [-0.586, 2] will be fine. You can verify this, given an input: <input type="range" min="-0.5857864376269049" max="2" value="-0.5857864376269049"> The input.valueAsNumber is -0.585786437626905 (note the rounding), and after calling input.checkValidity(), input.validity.rangeUnderflow is true. Changing the minimum to -0.585786437626905 fixes this problem. The other problem here is that the default number format (number.toLocaleString) will only give you three decimal places, so to be compatible with Observable’s Range input, you need the number input to be valid, too. So I recommend using -0.586 as the minimum, or if you really want a high precision input, pass {format: x => x} to force the number to display all the digits.

Thanks, Mike. I had already figured out how to avoid the problem. It's just that that weird number came out as a calculation -- 2 * (Math.cos(Math.PI / 4) - 1) and I thought it was worth mentioning. From here on, limits are best written as literals!

This behavior has been substantially improved in 0.7.18. Hope this helps! https://github.com/observablehq/inputs/releases/tag/v0.7.18

Can we change the style (color, width, height, etc.) of the slider?

You can style it with external CSS, but this is not recommended. Observable Inputs are intended to provide a well-designed, consistent appearance by default. For more customization, see https://observablehq.com/@bartok32/diy-inputs

When the "step" is provided at the same time as a "transform", the Input does not update I noticed that in this notebook https://observablehq.com/@mbostock/sine-cosine

I’m working on it. https://github.com/observablehq/inputs/issues/176

Seems like transform is not working?

It appears to be working for me. When the thumb is in the middle of the range, the value is ~10 (rather than ~50).

Ah I see, I misunderstood how transform works, whoops

How can I change disabled option dynamically?

Set the attribute directly on the two input elements of the form that is returned. For example with D3: > d3.select(viewof d).selectAll("input").attr("disabled", "disabled") // disable > d3.select(viewof d).selectAll("input").attr("disabled", null) // enable

Thanks, I got it.