Formatting Array numbers in certain pattern

Question

I have read multiple posts on here in other languages, however it didn't quite help me.

Let's say I have an array, which could be anything from:

[0,1,2,4,5,6,7,10]

to:

[1194,1195,1199,1299]

What I need to do, is find out what numbers are missing within the sequence. These arrays coulr be out of order too.

Example 1 would result in:

"Missing Frames = 3, 8-9"

Example 2 would result in:

"Missing Frames = 1196-1198, 1200-1298"

Currently, I have found the missing frames, but I can't figure out how to format them like above strings, instead, I'm just building an array.

Here is what I've done so far:

DEMO: http://jsfiddle.net/qBcD6/2/

Any Ideas?

themerlinproject · Accepted Answer · 2014-04-22 02:07:05Z

1

There is probably a more elegant way to do this, but this will do the job for you (jsfiddle demo):

filesArray = [1195, 1201, 1202, 1203, 1205, 1001, 1002, 1004];
filesArray.sort();
var arrayLength = filesArray.length;
var lastFrame = filesArray[arrayLength - 1];
var firstFrame = filesArray[0];
var loopLength = lastFrame - firstFrame;
var missingArrayIndex = 0;
var missingFrames = new Array();
var missingFramesString = "";
for (var i = 0; i <= loopLength; i++) {

    currentFrame = firstFrame + i;
    console.log("currentFrame is "+(currentFrame)+" and last frame was "+missingFrames[missingArrayIndex-1]);

    if (!isInArray(currentFrame, filesArray))
    {

        missingFrames[missingArrayIndex] = currentFrame;

        // if the currentFrame is not the last missingFrame+1, then it is new sequence

        if( currentFrame !== missingFrames[missingArrayIndex-1]+1)
        {
            missingFramesString = missingFramesString + currentFrame;

        }

    missingArrayIndex++;

    // if not a missing frame and the currentFrame-1 was a missingFrame then it is last of sequence
    } else if( currentFrame == missingFrames[missingArrayIndex-1] +1 )    {
        if (missingFramesString.indexOf(missingFrames[missingArrayIndex-1]) >= 0)
            missingFramesString = missingFramesString + ",";
        else missingFramesString = missingFramesString + "-" + missingFrames[missingArrayIndex-1] + ",";
    }
}

// remove last comma
missingFramesString = missingFramesString.replace(/,\s*$/, "");

$('body').html("Missing Frames = " + missingFramesString);

function isInArray(value, array) {
    return array.indexOf(value) > -1;
}

edited Apr 22, 2014 at 2:07

answered Apr 22, 2014 at 1:44

themerlinproject

3,5825 gold badges40 silver badges55 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Shannon Hochkins Over a year ago

This works great!, however there's one small problem, I can't seem to figure out why it formats this array [1195, 1201, 1202, 1203, 1205, 1001, 1002, 1004] differently, as in I get 1003-1003 in the output

XeroxDucati · Accepted Answer · 2014-04-22 01:52:37Z

0

Something like this? Mostly from memory, didnt get a chance to fully test against your fiddle..

var missingFormatted = missingFrames[0];
var current = missingFormatted;
for(var i = 1; i < missingFrames.length-1; i++)
{
    if(missingFrames[i]-current > 1)
    {
        if(missingFrames[i-1] != current)
            missingFormatted = missingFormatted + "-" + missingFrames[i-1];

        missingFormatted = missingFormatted + "," + missingFrames[i];
    }
}

answered Apr 22, 2014 at 1:52

XeroxDucati

5,2404 gold badges42 silver badges66 bronze badges

Comments

jacobappleton · Accepted Answer · 2014-04-22 16:32:26Z

0

Try this:

var frames = [0,1,2,4,5,6,7,10];

var convertIntArrayToStringsWithConsecutives = function(arr) {
    var i = 0, result = [];

    // Make sure we don't over-step the array
    for(i; i < arr.length - 1; i++) {
        // If next element is not consecutive
        if(arr[i + 1] !== (arr[i] + 1)) {
            // Print either single element when there is no gap
            if(arr[i] + 1 === arr[i+1] - 1) {
                result.push(arr[i] + 1);
            } else {
                // Or the two elements either end of the gap
                result.push((arr[i] + 1) + '-' + (arr[i+1]-1));
            }
        }
    }
    return result;
}

$('body').html("Missing Frames = " + convertIntArrayToStringsWithConsecutives(frames.sort(function (a,b) {
return a - b;
}))).toString());

Tested here:

http://jsfiddle.net/5k86J/6/

edited Apr 22, 2014 at 16:32

answered Apr 22, 2014 at 2:03

jacobappleton

5488 silver badges22 bronze badges

5 Comments

Shannon Hochkins Over a year ago

This doesn't work if I pass it an array like this: [0058,0117,0002,0004,0005,0006,0007,0010]

jacobappleton Over a year ago

What behavior do you expect with this input?

jacobappleton Over a year ago

The simplest way I can think of to handle your input would be to sort the array first, but I'm not sure if this is the behavior you require. developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…

jacobappleton Over a year ago

One last thing, how do you get the leading zeros in your numbers? Are they actually strings? Javascript sees these as octal values (at least in chrome), and you get unexpected results for something like 0117 which is actually 79 in decimal.

Shannon Hochkins Over a year ago

That's okay, I'll just read them as an int not a float and that should fix that issue,

Collectives™ on Stack Overflow

Formatting Array numbers in certain pattern

3 Answers 3

1 Comment

Comments

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related