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Why does a number get its last 2 digits turned to 0?

Use
Hi, so I was working on my discord bot with some user ids that I stored in a database, which then I will get back to ping them or give them roles.
Problem
Though here's the problem, in the database they get turned from ex: 533692905387196429 to 533692905387196400. I tried setting that to a String, and it worked, in the database, it's stored fully how it's supposed to be. But, when I get them back from the database and turn them into a number or an integer they get turned back to ex: 533692905387196400.
Tried using
I tried using parseInt(), parseFloat() and Number() but all of them give the same result.
More info
Also if I remove 2 digits for example: 533692905387196429I remove 19 from there, it will give back 533692905387(19)6429 instead of 533692905387196429 and instead of 533692905387196400.
Any help is appreciated!

So, Number.MAX_SAFE_INTEGER is 9007199254740991 (which is 253 - 1). Your number is too large to hold full precision.
If you want a number with that level of digits and precision, you can use BigInt and then you will have to be very careful how you use that BigInt as it cannot be directly used in place of a regular Number type, but it can hold infinite precision and you can do math between two BigInt values.
Whether it's best used as a BigInt or as a String really depends upon what you're doing with it. If these are just some sort of ID that you aren't actually doing numeric operations with, then you can just keep it as a string.

The number is too big, so Javascript doesn't keep full precision!
> 533692905387196429
533692905387196400
You can resolve this by storing them as strings:
> '533692905387196429'
'533692905387196429'
You shouldn't need to do any mathematical operations with Discord IDs so there shouldn't be any issue storing and treating them as strings everywhere.

Dynamically splitting an array depending on character count

I have an array like so:
const testArray = [ 'blah', 'abc​testtt​​', 'atestc​', 'testttttt' ]
I would like to split the string once it reaches a certain character count, for example lets use 10 characters. Also, I would like the output to swap itself to be able to use within 10 characters. Please see the expected output below if this doesn't really make sense to you. Please assume that each item in the array will not be above 10 characters just for example purpose.
So once the testArray reaches 10 characters I would like the next item to be under a new variable maybe? Not sure if thats the best way of doing this.
Something like this maybe? Again this may be very inefficient, if so please feel free to use another method.
const testArray = [ 'blah', 'abctesttt​​', 'atestc', 'testttttt' ]
if ((testArray.join('\n')).length) >= 10 {
/* split the string into parts and store it under a variable maybe?
console.log((the_splitted_testArray).join('\n')); */
}
Expected output:
"blah
atestc" //instead of using "abctesttt" it would use "atestc" as it's the next element in the array and it also avoids reaching the 10 character limit, if adding "atestc" caused the character limit to go over 10, I would like it to check the next element and so on
"abctesttt" // it can't add the remaining "testttttt" since that would cause the character limit to be reached
"testttttt"

First of all, as you can't create a new variable out of nowhere at run time, you are probably going to use a "parent"-array, which then contains the actual strings with a length of 10 maximally.
For the grouping you probably have to design an algorithm yourself. My first idea for an algorithm is something like below. Probably not the best and most efficient way (as the description of "efficient" depends on your personal priorities), but feel free to optimise it yourself :)
Walk through $testArray[], sort all strings into a new two-dimensional array: $stringLength[$messagesWithSameLength[]]. Like array(1=>array('.','a'),2=>array('hi','##',...),...)
Now, always try to get as many strings together as possible. Start with one of the longest strings, calculate the remaining space and get a string suiting best into it. If none fits, start a new group.
Always try to use the space as good as possible

Regex for finding all the numbers between any two numeric values (range) in JavaScript [duplicate]

This question already has answers here:
How to match numbers between X and Y with regexp?
(7 answers)
Closed 7 years ago.
First of all, i know Regular expressions isn't the best tool to achieve what I want here. I have done enough research to know that bit. Still, The problem I am stuck in requires me to make up a regex to find the values between some lower and upper bound values.
So here is the problem, I have a large set of data, let's say ranging between 1 and 1000000. That data is not under my direct control, I cannot manipulate the data directly. Only way of finding out (searching) some values from that data is regex.. Now, the user can give two values, a minimum value and a maximum value and I need to construct a regex based on these two values and then query the large data set using the regex to get all the values lying between the set range. So, if my data contains [1,5,7,9,15,30,45,87] and user sets the range min:10, max:40. The regex should filter out values 15, 30.
From whatever I have searched, I know it is very much possible to build a regex for finding out values between fixed values (if we know them beforehand) for example, values between 1 to 100 can be found by:
^(100|[1-9][0-9]?)$
But what gets so tricky about my problem is that the input range can be anything from pretty much 1 digit values to up to 10 digit values. 10000-550000 can be an example user input for a large data set.
I know this will require some complex logic and loops involved on the basis of number of digits in the lower bound and number of digits in the upper bound of the range and then some recursive or other magical logic to build a regex that covers all the number lying in that range.
I've been filling up pages to come up with a logic but I'm afraid it surpasses my knowledge of regex. If anyone has ever done something like this before or try to point me in the right direction or attempt it him/herself - it'll be quite helpful. Thanks.
The language I will be using this in is JavaScript and I read somewhere that JS doesn't support conditional regex, keeping that in mind, solution doesn't have to be in specific to a language.

If your task is to get numbers between min and max value from the dataset, you can try filter method.
Var filteredResults = Dataset.filter(function(item){
If(item < max && item > min)
Return item
}
)

Find numbers at a specific position

I'm trying to find an expression for JavaScript which gives me the two characters at a specific position.
It's always the same call so its may be not too complicated.
I have always a 10 char long number and i want to replace the first two, the two at place 3 and 4 or the two at place 5 and 6 and so on.
So far I've done this:
number.replace(/\d{2}/, index));
this replace my first 2 digits with 2 others digits.
but now I want to include some variables at which position the digits should be replaced, something like:
number.replace(/\d{atposx,atpox+1}/, index));
that means:
01234567891
and I want sometimes to replace 01 with 02 and sometimes 23 with 56.
(or something like this with other numbers).
I hope I pointed out what I want.

This function works fine:
function replaceChars(input, startPos, replacement){
return input.substring(0,startPos) +
replacement +
input.substring(startPos+replacement.length)
}
Usage:
replaceChars("0123456789",2,"55") // output: 0155456789
Live example: http://jsfiddle.net/FnkpT/

Numbers are fairly easily interpreted as strings in JS. So, if you're working with an actual number (i.e. 9876543210) and not a number that's represented by a string (i.e. '987654321'), just turn the number into a string (''.concat(number); ) and don't limit yourself to the constraints of what you can do with just numbers.
Both of the above examples are fine (bah, they beat me to it), but you can even think about it like this:
var numberString = ''.concat(number);
var numberChunks = numberString.match(/(\d{2})/g);
You've now got an array of chunks that you can either walk through, switch through, or whatever other kind of flow you want to follow. When you're done, just say...
numberString = numberChunks.join('');
number = parseInt(numberString, 10);
You've got your number back as a native number (or skip the last part to just get the string back). And, aside from that, if you're doing multiple replacements.. the more replacements you do in the number, the more efficient breaking it up into chunks and dealing with the chunks are. I did a quick test, and running the 'replaceChars' function was faster on a single change, but will be slower than just splitting into an array if you're doing two or more changes to the data.
Hope that makes sense!

You can try this
function replaceAtIndex(str,value,index) {
return str.substr(0,index)+value+str.substr(index+value.length);
}
replaceAtIndex('0123456789','X',3); // returns "012X456789"
replaceAtIndex('0123456789','XY',3); // returns "012XY56789"

How to compare locale dependent float numbers?

I need to compare a float value entered in a web form against a range. The problem is that the client computers may have various locale settings, meaning that user may use either "." or "," to separate the integer part from decimal one.
Is there a simple way to do it? As it is for an intranet and that they are only allowed to use IE, a VBScript is fine, even if I would prefer to use JavaScript.
EDIT: Let me clarify it a bit:
I cannot rely on the system locale, because, for example, a lot of our french customers use a computer with an english locale, even if they still use the comma to fill data in the web forms.
So I need a way to perform a check accross multiple locale "string to double" conversion.
I know that the raise condition is "what about numbers with 3 decimal digits", but in our environment, this kind of answer never happen, and if it happens, it will be threated as an out of range error due to the multiplication by a thousand, so it's not a real issue for us.

In Javascript use parseFloat on the text value to get a number. Similarly in VBScript use CDbl on the text value. Both should conform to the current locale settings enforce for the user.

This code should work:
function toFloat(localFloatStr)
var x = localFloatStr.split(/,|\./),
x2 = x[x.length-1],
x3 = x.join('').replace(new RegExp(x2+'$'),'.'+x2);
return parseFloat(x3);
// x2 is for clarity, could be omitted:
//=>x.join('').replace(new RegExp(x[x.length-1]+'$'),'.'+x[x.length-1])
}
alert(toFloat('1,223,455.223')); //=> 1223455.223
alert(toFloat('1.223.455,223')); //=> 1223455.223
// your numbers ;~)
alert(toFloat('3.123,56')); //=> 3123.56
alert(toFloat('3,123.56')); //=> 3123.56

What we do is try parsing using the culture of the user and if that doesn't work, parse it using an invariant culture.
I wouldn't know how to do it in javascript or vbscript exactly though.

I used KooiInc's answer but change it a bit, because it didn't reckon with some cases.
function toFloat(strNum) {
var full = strNum.split(/[.,]/);
if (full.length == 1) return parseFloat(strNum);
var back = full[full.length - 1];
var result = full.join('').replace(new RegExp(back + '$'), '.' + back);
return parseFloat(result);
}

Forbid using any thousands separator.
Give the user an example: "Reals should look like this: 3123.56 or 3123,56". Then simply change , to . and parse it.
You can always tell user that he did something wrong with a message like this:
"I don't understand what you mean by "**,**,**".
Please format numbers like "3123.56."