2016年2月4日 · There's been a lot of questions on rounding by significant figures, and answers that that provides a new method to do the rounding, such as: Rounding to an arbitrary number of significant digits. Round a double to 2 decimal places. Most of these questions and solutions are around 2009~2010.

Most of the solutions given here either (a) don't give correct significant figures, or (b) are unnecessarily complex. If your goal is display formatting, then numpy.format_float_positional supports the desired behaviour directly. The following fragment returns the float x formatted to 4 significant figures, with scientific notation suppressed.

The posted answer was the best available when given, but it has a number of limitations and does not produce technically correct significant figures. numpy.format_float_positional supports the desired behaviour directly. The following fragment returns the float x formatted to 4 significant figures, with scientific notation suppressed.

2017年5月4日 · I needed significant-digit rounding for approximate and non-performance-critical computational purposes, and the format-parse round-trip through "G" format is good enough: public static double RoundToSignificantDigits(this double value, int numberOfSignificantDigits) { return double.Parse(value.ToString("G" + numberOfSignificantDigits)); }

2016年7月20日 · I would like to be able to round a number to n significant figures in SQL. So: 123.456 rounded to 2sf would give 120 0.00123 rounded to 2sf would give 0.0012 I am aware of the ROUND() function, which rounds to n decimal places rather than significant figures.

2008年10月15日 · For N significant integral (non-fractional) digits: • Divide the number by 10 N • Add 0.5 • Truncate the fraction digits (i.e., truncate the result into an integer) • Multiply by 10 N You can do this on any calculator, for example, that has an "INT" (integer truncation) operator.

2015年12月15日 · Rounding to significant figures is a lot easier in TSQL where the rounding method is based on rounding position, not number of decimal places - which is the case with .Net math.round. You could round a number in TSQL to negative places, which would round at whole numbers - so the scaling isn't needed. Also see this other thread. Pyrolistical's ...

2013年12月18日 · I am using excel and i want to display a value to a certain number of significant figures. I tried using the following equation =ROUND(value,sigfigs-1-INT(LOG10(ABS(value)))) with value replaced by the number I am using and sigfigs replaced with the number of significant figures I want. This formula works sometimes, but other times it doesn't.

2017年5月4日 · There is a difference between rounding a value to a number of significant figures and displaying a number of significant figures. 3 is already accurate to 3.s.f. so as a value it does not matter whether you have 3.00 or 3 as they are identical values; if you want to display all the significant figures then you want 3.00 and that is a very ...

2017年7月18日 · The accepted answer has limitations and does not produce technically correct significant figures in the general case. numpy.format_float_positional supports the desired behaviour directly. The following fragment returns the float x formatted to 4 significant figures, with scientific notation suppressed.