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I'm trying to filter an array to build another array with the results I get. But the bination of functions I have been using with jQuery haven't workk so far. So I would appreciate some advice about how to solve this.

Here is the example of what I'm trying to implement:

This is my first array:

var data =[salt.1200, salt.1100, salt.1000, salt.0900, salt.0800, salt.0700, current.1200, current.1100, current.1000, current.0900, current.0800, current.0700];

And from this array I would like to build two different arrays, one for salt and one from current.

I have tried to use a for loop with a jQuery grep function on it and split, but that didn't worked.

var plotsArray = [];
        for (var i=0; i<data.length; i++){
            plotsArray = jQuery.grep(data, function(a){
                return (a.split(".") == 'salt')
            });
        }
        console.log('plotsArray: '+plotsArray);

Also, I been trying to do is to read the first part of the string until the dot and then build an array base on that result. Using for example array filter, but I haven't figure it out how to read just until the dot.

I will appreciate any guidance on how to solve this.

Regards,

I'm trying to filter an array to build another array with the results I get. But the bination of functions I have been using with jQuery haven't workk so far. So I would appreciate some advice about how to solve this.

Here is the example of what I'm trying to implement:

This is my first array:

var data =[salt.1200, salt.1100, salt.1000, salt.0900, salt.0800, salt.0700, current.1200, current.1100, current.1000, current.0900, current.0800, current.0700];

And from this array I would like to build two different arrays, one for salt and one from current.

I have tried to use a for loop with a jQuery grep function on it and split, but that didn't worked.

var plotsArray = [];
        for (var i=0; i<data.length; i++){
            plotsArray = jQuery.grep(data, function(a){
                return (a.split(".") == 'salt')
            });
        }
        console.log('plotsArray: '+plotsArray);

Also, I been trying to do is to read the first part of the string until the dot and then build an array base on that result. Using for example array filter, but I haven't figure it out how to read just until the dot.

I will appreciate any guidance on how to solve this.

Regards,

• javascript
• jquery

Share Improve this question Follow edited Jan 4, 2013 at 12:58 Probandot asked Jan 4, 2013 at 12:52 ProbandotProbandot 19511 silver badge1717 bronze badges 6

• Does data contain strings? – pimvdb Commented Jan 4, 2013 at 12:54
• also doesn't a.split() return an array? a.split(".")[0] maybe? – NickSlash Commented Jan 4, 2013 at 12:56
• @pimvdb, data contain strings. – Probandot Commented Jan 4, 2013 at 13:02
• @NickSlash, a.split returns an array with two elements from the string [salt, 1200]. And I want to get an array with all the salt elements. Make sense? – Probandot Commented Jan 4, 2013 at 13:03
• not really no? ([array] == [string]) == false – NickSlash Commented Jan 4, 2013 at 13:07

 |  Show 1 more ment

7 Answers 7

Sorted by: Reset to default 3

I would do something more along the lines off this.

var plotsArray = [];
        for (var i=0; i<data.length; i++){
            if(data[i].indexOf('salt') >= 0){
            plotsArray.push(data[i]);           
        }
        console.log('plotsArray: '+plotsArray);

Make change here -

return (a.split(".")[0] == 'salt')

and your code will work. Working fiddle - http://jsfiddle/Lh8Pt/

Using you code I would do:

var plotsArray = [];

plotsArray.push($.grep(data, function(n,i){
   return n.split(".")[0] !== "salt";
}));

And please be sure that the data array contains strings.

I reckon your test should either be:

return a.split(".")[0] == "salt";

or

return a.indexOf("salt") == 0;

The latter might be better because it will not error out in the occasion that one of the array values doesn't contain a dot.

Using filter/map methods you could do something like:

var current = [], 
    salt = data.filter(
            function(a){
              var x = a.split('.'); 
              if (/current/i.test(x[0])) { this.push(x[1]); } 
 //                                        ^ = current
              return /salt/i.test(x[0])
             }, current
 //             ^ context
           ).map(
             function(b){
               return b.split('.')[1]}
           );

MDN about Array.filter

Try this: http://jsfiddle/afEGC/

var data = ['salt.1200', 'salt.1100', 'salt.1000', 'salt.0900', 'salt.0800', 'salt.0700', 'current.1200', 'current.1100', 'current.1000', 'current.0900', 'current.0800', 'current.0700'];

var asplit = new Array();
asplit['salt'] = new Array();
asplit['current'] = new Array();

​jQuery.each(data, 
          function(index,value)
             {
                 var split_value = value.split('.');
                   asplit[split_value[0]].push(split_value[1]);                                 
             });

console.log('salt: ' + asplit['salt']);

console.log('current: ' +​​​​​​​​​​​​​​​​ asplit['current']);​​​​

var saltArray = [];
    var currentArray = [];
    for(var i=0;i<data.length;i++){

        if(data[i].split('.')[0]=='salt'){

            saltArray.push(data[i]);

        }else{
           currentArray.push(data[i]);
         }
    }

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