Request for sigfig support

[SS-KyleSam]

Request for sigfig support

[hanna-kn]

This is already supported by the "read precision" (readprec) setting. This can be activated in qalc using set readprec. The number of significant digits in output can be changed using the precision or max decimals settings.

> help readprec

read precision (readprec)
If activated, numbers are interpreted as approximate with precision equal to the number of significant digits
(3.20 = 3.20+/-0.005).
(0* = off, 1 = always, 2 = when decimals)

> set readprec
> 1.23*2.1

  ≈ 1.2300±0.0050 × 2.100±0.050 ≈ 2.583±0.062

Qalculate also supports specification of the precision/uncertainty/error of a value using ± (or +/-), or the interval() and uncertainty() functions.

By default the precision of the result (uncertainty propagation) is determined using the variance formula, but interval arithmetic can also be used (this is controlled by the "interval arithmetic", or ia, setting). The common simple method of using the same number of significant digits in output as the number with the least number of significant digits in input is not supported.

With "read precision" enabled 1.23*2.1 will return 2.583±0.062 (or 2.583±0.072 with interval arithmetic enabled). Note that ± will by default be omitted for values with higher precision (e.g. 1.23 * 2.10 ≈ 2.6)

[SS-KyleSam]

Apologies for adding a request without doing the proper research. The real implantation is better than what I requested.