atlas-pretty-hrtime

Converts a time in nanoseconds to a pretty string in the most convenient units.

---

install

npm install --save atlas-pretty-hrtime

why

Printing times is annoying, so this is me thinking about it once and hopefully never again. If you are doing performance testing, you will encounter time diffs between different points in your code. With this module, you don't need to worry about how to print those times in various units with varying precision -- it's done automatically for you.

examples

The exported function takes a time in nanoseconds, an optional precision integer and returns a string. The default precision is 3 decimal places, and the maximum unit is hours.

1const pretty = require("atlas-pretty-time");
2// all times in nanoseconds
3const times = [  
4                 // output units:
5  0,             // ns
6  123,           // ns
7  1234,          // us
8  12345,         // us
9  123456,        // us
10  1234567,       // ms
11  12345678,      // ms
12  123456789,     // ms
13  1234567890,    // sec
14  12345678901,   // sec
15  123456789012,  // min
16  1234567890123, // min
17  12345678901234 // hr
18]
19times.forEach(time => {
20  // round to 1 decimal place
21  const prettyTime = pretty(time, 1);
22  console.log(prettyTime)
23});
24// 0.0ns
25// 123.0ns
26// 1.2us
27// 12.3us
28// 123.5us
29// 1.2ms
30// 12.3ms
31// 123.5ms
32// 1.2sec
33// 12.3sec
34// 2.1min
35// 20.6min
36// 3.4hr

caveats

units

Only accepts times in nanoseconds, because supporting multiple input units is outside the scope of this package. This package is primarily for printing time diffs, which should not be in milliseconds or seconds if you're using high resolution time. See atlas-hrtime.

fractional minutes and hours

For simplicity, this module does not decompose fractional minutes into "minutes and seconds" (and similarly with hours). This doesn't bother me much, so I'm unlikely to implement something like:

1console.log(pretty(123456789012, 1))
2// 2min 3sec

specifying return units

At the moment, this is not possible, but I may implement it in the future if I need finer-grained control on the output units:

1console.log(pretty(123456789012, 1, "sec"))
2// 123.5sec