Round to a Specified Number of Significant Digits

Rounds a numeric array to a specified number of Significant Digits.

Description

sd_round stands for "Significant Digits Round".

This program rounds a 2-d matrix of numbers to a specified number of significant digits.

This program support five different styles of rounding the last digit: to the nearest integer, up, down, toward zero, and away from zero.

This program supports real and complex numbers.

The program outputs the rounded array, a cell string of the rounded matrix, the number of digits, to the left and right of the decimal place.

This program is useful for presenting scientific data that requires rounding to a specifid number of significant digits for publication.

Acknowledgements

The author wishes to acknowledge the following in the creation of this submission:
round2, FIX2, ROUND2
This submission has inspired the following:
Round with significant digits

• MATLAB release: MATLAB 7.5 (R2007b)

[Dimitri Shvorob]

.. So how does your submission improve on the older ones?

[Edward Zechmann]

Dimitri, this submission fixed the error for rounding numbers less than 1. There is an additional example. The number of digits to the left and right of the decimal point is recalcualted after rounding, because rounding can affect the number of digits to the left and right of the decimal point. Please post a comment or send me an e-mail if you find any more bugs or have any questions. Thanks for your previous comments.

[Peter]

Is it a bug that:

sd_round(1.5000, 2)

==> 1.5000

I hoped for 1.5 as result.

[mathworks2011]