How to get index value from array?

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I am trying to find the index value of the data from array who's contain 800 data approximately and it is also contain lots of same value.

What I have tried:

copyarray = yAxisdata.slice(0);  
length=yAxisdata.length;   
for (k = 0; k <length-1; k++)
{ 
     maxvalue = copyarray[k];
     indexvalue = yAxisdata.indexOf(maxvalue);
}

Above code is just an example of my long code. I am using this code to find the index of a number which is available into the array, This code is working perfectly but the problem is, if this array contain a multiple same value for example if i have 1,1 number is available in array at that time the above code is always provide an index value of first 1 and skip the second 1.

Posted 18-Jan-21 20:29pm

Member 14743579

Updated 18-Jan-21 22:52pm

v2

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Maciej Los 19-Jan-21 2:50am

And you're suprised that indexOf returns the index of first instance of value in the array?

Member 14743579 19-Jan-21 3:06am

I am trying to get the index values of all data which is available into the array including same values if you have a solution about it please tell me.

Richard MacCutchan 19-Jan-21 6:33am

Then you will need to create a new array to hold all the index values that you find.

Richard Deeming 19-Jan-21 4:44am

Is this C#, or is it Javascript? They are two completely different languages.

The int declarations would seem to suggest C#. But the slice call would suggest Javascript.

Member 14743579 19-Jan-21 4:51am

This is javascript code, I Added the int for understanding. Now i am going to remove int part from my code if you confused.

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Maciej Los · Answer 1 · 2021-01-18T20:53:00

Solution 1

Well... below code returns the first occurance of value in the array.

JavaScript

indexvalue = yAxisdata.indexOf(maxvalue);

To get second occurance of value, use this:

JavaScript

secondindex = yAxisdata.indexOf(maxvalue, yAxisdata.indexOf(maxvalue)+1);

To get more examples, visit this thread: javascript - How to get the position of the second occurrence? - Stack Overflow[^]

Posted 18-Jan-21 20:53pm

Maciej Los

Comments

Member 14743579 19-Jan-21 3:04am

I know about this code but my problem is I have an arraylist which contain 800 data approximately including lots of same data, I want to get the index values of all the values which is an available into the arraylist include the same values.

Note: I don't know how many values are same in this array please give me a solution if you know.

CPallini 19-Jan-21 3:10am

5.

Member 14743579 19-Jan-21 3:19am

ok, but I want to find the index of every number which is available in array including same numbers.

Maciej Los 19-Jan-21 3:38am

So, what's stoppping you? You've got an idea! Use it!

Maciej Los 19-Jan-21 3:37am

Thank you, Carlo.