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Javascript – Using setInterval in a for loop to iterate through multiple arrays?

I have a for loop that i need to use to iterate through 6 arrays of equal length at the same time but at set intervals. I’m using Javascript. what i am having trouble with is implementing the intervals. Basically what i am trying to do is make the for loop iterate through each array at an interval of 1000ms, so that it prints out the console logs at a rate of 1000ms. The ‘iteration complete’ log only after the array is done. meaning after every index has been iterated through at a rate of 1000 ms per index

if anyone has any advice please i would greatly appreciate your input.

const noteW = [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
const noteE = [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
const noteR = [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
const noteI = [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
const noteO = [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
const noteP = [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]

for (i=0;i<noteW.length;i++){
  

      if (noteW[i] === 1) {
        console.log('shieeet1');
      }
      if (noteE[i] === 1) {
        console.log('shieeet2');
      }
      if (noteR[i] === 1) {
        console.log('shieeet3');
      }
      if (noteI[i] === 1) {
        console.log('shieeet4');
      }
      if (noteO[i] === 1) {
        console.log('shieeet5');
      }
      if (noteP[i] === 1) {
        console.log('shieeet6');
      }
      console.log('Iteration complete');
    }

I have tried using setintervals but its not working for some reason.

Tags:

2

Answers


  1. 0

    You can achieve your purpose by using a setTimeout with Promise which resolves after 1 second.

    A shorter version of the working code will look like:

    const notes = [
  [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1],
  [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1],
  [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1],
  [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1],
  [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1],
  [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1],
];

async function printLogs() {
  for (let i = 0; i < notes[0].length; i++) {
    for (let j = 0; j < notes.length; j++) {
      if (notes[j][i] === 1) {
        console.log(`shieeet${j + 1}`);
      }
    }
    console.log(`${i + 1}th iteration complete`);

    // Wait for 1000ms before continuing the loop
    await new Promise((resolve) => setTimeout(resolve, 1000));
  }
  console.log("Loop completes"); // <--- From your comment put your Iteration complete here if you want.
  
}

printLogs();
    .as-console-wrapper { max-height: 100% !important; top: 0; }

    Alternative solution:

    You might be using setInterval wrongly because of which it was not working for you. Here’s how you can use it:

    const notes = [
  [1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1],
  [0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1],
  [1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1],
  [0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1],
  [1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1],
  [0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1],
];
let i = 0;
function printLogs() {
  if (i >= notes[0].length) {
    clearInterval(interval);
    console.log(`Iteration complete`);
    return;
  }
  for (let j = 0; j < notes.length; j++) {
    if (notes[j][i] === 1) {
      console.log(`shieeet${j + 1}`);
    }
  }
  i++;
}
const interval = setInterval(printLogs, 1000);
    .as-console-wrapper { max-height: 100% !important; top: 0; }
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  2. 0

    From what I understand from your question, you want to have only one message each second.

    IMHO, the simplest is to use a generative function.

    const
  delay = 1000  // ms
, noteW = [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
, noteE = [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
, noteR = [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
, noteI = [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
, noteO = [1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
, noteP = [0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1]
, Notes =
  [ [noteW, 'shieeet1'], [noteE, 'shieeet2'], [noteR, 'shieeet3']
  , [noteI, 'shieeet4'], [noteO, 'shieeet5'], [noteP, 'shieeet6']
  ]
, iterator = 
    (function* ()
      {
      for (let i=0; i < noteW.length; i++ )
        {
        for (let [note,resp] of Notes)
          {
          if (note[i]) yield resp;
      } } }
    )()
, refInterval = 
    setInterval( () => 
      {
      let iteration = iterator.next();
      //console.clear();
      if (iteration.done)
        {
        console.log( 'Iteration complete' );
        clearInterval( refInterval );
        }
      else
        console.log( iteration.value );
      }
      , delay
    );
    .as-console-wrapper    { max-height: 100% !important;top: 0; }
.as-console-row::after { display: none !important;           }
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