ResistorJS

ResistorJS is a Javascript library intended to compose electronical resistors.

Using Resistors in Code

In order to instantiate an 100 Ohm resistor, we simply call new Resistor(100). In order to compose several resistors, the composite resistor types SeriesResistor and ParallelResistor are available.

var r1 = new Resistor(100);
var r2 = new Resistor(150);
// Combining resistors
var inSeries = r1.series(r2); // type: SeriesResistor
var inParallel = r1.parallel(r2); // type: ParallelResistor

// Computing resulting resistors
inSeries.getOhmage() // 250
inParallel.getOhmage() // 60

// Drawing to DOM
r1.draw(div1);
r2.draw(div2);
inSeries.draw(div3);
inParallel.draw(div4);

Calling Resistor.draw(element) generates an SVG from the constructed Resistor object. Above code will render something like this:

Computing approximations

Sometimes, one wants to use ohmages in an electronical circuit that simply are not available. By cleverly combining a sufficient number of available resistors, one can approximate the needed values. For instance, using only 100Ohm and 100Ohm resistors, one can construct a (sufficiently close to) 127Ohm resistor like so:

main.js contains an example application using dynamic programming that computes sufficiently good approximations for resistor values within a set range.