Round to Electronic Component Values

Round numeric array values to IEC 60063 resistor/capacitor values (E-Series of preferred numbers).

ROUND63 rounds numeric values to electronic component values defined in IEC 60063 (preferred numbers for resistor, capacitor, and inductor values, previously IEC 63). By default the rounding bin edges approximate component tolerance boundaries: an optional input selects round-to-nearest, rounding up, and rounding down.

Supports E-series E3, E6, E12, E24, E48, E96, and E192. For example, E6 = [...,10,15,22,33,47,68,100,150,220,...]

Reference: https://en.wikipedia.org/wiki/E_series_of_preferred_numbers

Bonus Functions

The bonus function ROUND63_VIEW creates a figure that demonstrates how ROUND63's rounding bin edges correspond to the component tolerance boundaries.

The bonus function ROUND63_TEST includes many tests of the nominal and edgecase behavior.

Examples

>> round63(500, "E12")
ans = 470

>> round63([5,42,18,100], 'E12')
ans = [4.7, 39, 18, 100]

>> round63([5,42,18,100], 'E6') % default = 'harmonic'
ans = [4.7, 47, 22, 100]
>> round63([5,42,18,100], 'E6', 'up')
ans = [6.8, 47, 22, 100]
>> round63([5,42,18,100], 'E6', 'down')
ans = [4.7, 33, 15, 100]
>> round63([5,42,18,100], 'E6', 'arithmetic')
ans = [4.7, 47, 15, 100]

>> [Y,idx,pns,edg] = round63([5,42,18,100], 'E3')
Y   = [4.7, 47, 22, 100]
idx = [  1,  4,  3,   5]
pns = [4.7; 10; 22; 47; 100]
edg = [2.9971; 6.3946; 13.75; 29.971; 63.946; 137.5]

>> [Y,idx,pns,edg] = round63([-Inf,Inf,NaN;-1,0,1], 'E3')
Y   = [NaN, NaN, NaN; NaN, NaN, 1]
idx = [NaN, NaN, NaN; NaN, NaN, 1]
pns = 1
edg = [0.63946; 1.375]