Sine in JS and in Processing

sine.js

var sprintf = require('sprintf').sprintf; // only needed for formatting the console output

var counter = 0;
var increase = Math.PI * 2 / 50;
var i=0;

setInterval(function() {
    var val = Math.sin(counter-Math.PI/2)/2+0.5;
    counter += increase;
    console.log(sprintf("%.3f %" + Math.round(val*60) + "s", val, "."));
}, 20);

sine.js.output

% node sin.js
0.000 .
0.004 .
0.016 .
0.035  .
0.062    .
0.095      .
0.136        .
0.181           .
0.232              .
0.287                 .
0.345                     .
0.406                        .
0.469                            .
0.531                                .
0.594                                    .
0.655                                       .
0.713                                           .
0.768                                              .
0.819                                                 .
0.864                                                    .
0.905                                                      .
0.938                                                        .
0.965                                                          .
0.984                                                           .
0.996                                                            .
1.000                                                            .
0.996                                                            .
0.984                                                           .
0.965                                                          .
0.938                                                        .
0.905                                                      .
0.864                                                    .
0.819                                                 .
0.768                                              .
0.713                                           .
0.655                                       .
0.594                                    .
0.531                                .
0.469                            .
0.406                        .
0.345                     .
0.287                 .
0.232              .
0.181           .
0.136        .
0.095      .
0.062    .
0.035  .
0.016 .
0.004 .
0.000 .
0.004 .
0.016 .
0.035  .
0.062    .
0.095      .
0.136        .
0.181           .
0.232              .
0.287                 .
0.345                     .
0.406                        .
0.469                            .
0.531                                .
0.594                                    .
0.655                                       .
0.713                                           .
0.768                                              .
0.819                                                 .
0.864                                                    .
0.905                                                      .
0.938                                                        .
0.965                                                          .
0.984                                                           .
0.996                                                            .
1.000                                                            .
0.996                                                            .
0.984                                                           .
0.965                                                          .
0.938                                                        .
0.905                                                      .
0.864                                                    .
0.819                                                 .
0.768                                              .
0.713                                           .
0.655                                       .
0.594                                    .
0.531                                .
0.469                            .
0.406                        .
0.345                     .
0.287                 .
0.232              .
0.181           .
0.136        .
0.095      .
0.062    .
0.035  .
0.016 .
0.004 .
0.000 .
0.004 .
0.016 .
0.035  .
0.062    .
0.095      .
0.136        .
0.181           .
0.232              .
0.287                 .
0.345                     .
0.406                        .
0.469                            .
0.531                                .
0.594                                    .
0.655                                       .
0.713                                           .
0.768                                              .
0.819                                                 .
0.864                                                    .
0.905                                                      .
0.938                                                        .
0.965                                                          .
0.984                                                           .
0.996                                                            .
1.000                                                            .
0.996                                                            .
0.984                                                           .
0.965                                                          .
0.938                                                        .
0.905                                                      .
0.864                                                    .
0.819                                                 .
0.768                                              .
0.713                                           .
0.655                                       .
0.594                                    .
0.531                                .
0.469                            .
0.406                        .
0.345                     .
0.287                 .
0.232              .
0.181           .
0.136        .
0.095      .
0.062    .
0.035  .
0.016 .
0.004 .
0.000 .
0.004 .
0.016 .
0.035  .
0.062    .
0.095      .
0.136        .
0.181           .
0.232              .
0.287                 .
0.345                     .
0.406                        .
0.469                            .
0.531                                .
0.594                                    .
0.655                                       .
^C%

sine.pde

float counter = 0;
float increase = PI * 2 / 200;
int i = 0;

void draw() {
  float value = (sin(counter-PI/2)/2+0.5);
  counter += increase;
  background(255*value);
  println(value);
  i += 1;  
}