I do have a JSON string which I receive by ajax which is correctly ordered:
{"label":"Gr\u00f6\u00dfe","values":{"4302":"XS","4184":"S","4185":"M","4186":"L","4187":"XL","4188":"XXL","5165":"3XL","4340":"4XL"}}
This JSON fills a select. The problem is, that the options are automatically reordered ( I don't know why? ) based on the value key which means that I do not get the correct option order for the select.
The option looks like:
S,M,L,XL,XXL,XS,4XL,3XL
The correct order should be
XS,S,M,L,XL,XXL,3XL,4XL
What can I do to get the correct order?
In JavaScript there is no guaranteed order for the properties on objects. Instead, you should use an array in your JSON to ensure order. Something like this:
{"label":"Gr\u00f6\u00dfe","values":[{"4302":"XS"},{"4184":"S"}, ...]}
You can format the objects in the values array anyhow you'd like, but the idea is when concerned with order, use arrays.
I have the the following data being returned by my api.
[{"category":"Amazon","month":"Feb","total":9.75},
{"category":"Amazon","month":"Mar","total":169.44},
{"category":"Amazon","month":"Apr","total":10.69},
{"category":"Amazon","month":"May","total":867.0600000000001},
{"category":"Amazon","month":"Jun","total":394.43999999999994},
{"category":"Amazon","month":"Jul","total":787.2400000000001},
{"category":"Amazon","month":"Aug","total":1112.4400000000003},
{"category":"Amazon","month":"Sep","total":232.86999999999998},
{"category":"Amazon","month":"Oct","total":222.26999999999998},
{"category":"Amazon","month":"Nov","total":306.09999999999997},
{"category":"Amazon","month":"Dec","total":1096.2599999999998}]
I want to format it so that the months are all grouped under each category like this:
[{"category":"Amazon","month":{"Jan":9.75,"Feb":9.75,"Mar":9.75,"Apr":9.75,etc...}]
How can I do this with javascript?
What I'm ultimately trying to do is to display some pivoted data in a table. I'm not sure what the best design is to accomplish this.
Right now, I'm just setting up a table dynamically and adding in the data corresponding to each row. Are there better design patterns for doing this?
You can reduce the array of objects to an object using the categories as keys, and adding the months, and then map it back to an array again
var arr = [{"category":"Amazon","month":"Feb","total":9.75},
{"category":"Amazon","month":"Mar","total":169.44},
{"category":"Amazon","month":"Apr","total":10.69},
{"category":"Amazon","month":"May","total":867.0600000000001},
{"category":"Amazon","month":"Jun","total":394.43999999999994},
{"category":"Amazon","month":"Jul","total":787.2400000000001},
{"category":"Amazon","month":"Aug","total":1112.4400000000003},
{"category":"Amazon","month":"Sep","total":232.86999999999998},
{"category":"Amazon","month":"Oct","total":222.26999999999998},
{"category":"Amazon","month":"Nov","total":306.09999999999997},
{"category":"Amazon","month":"Dec","total":1096.2599999999998}];
var o = arr.reduce( (a,b) => {
a[b.category] = a[b.category] || [];
a[b.category].push({[b.month]:b.total});
return a;
}, {});
var a = Object.keys(o).map(function(k) {
return {category : k, month : Object.assign.apply({},o[k])};
});
console.log(a);
I would take the following approach:
Write down on a piece of paper how to solve the problem (the "algorithm").
Flesh out this algorithm with more details. Sometimes this is called "pseudo-code".
Convert the pseudo-code into JavaScript.
For instance, your algorithm might look like this:
Create a new thing to hold the results.
Loop through the elements in the input.
For each element in the input, update the results thing.
Return the result.
Sometimes it helps to read out the algorithm aloud to yourself. Or animate the algorithm on a blackboard. Or talk through the algorithm with someone nearby.
The pseudo-code might be:
Create a new array containing a new object to hold the results, with a category property set to "Amazon", and a months property set to an empty object.
Loop through the elements in the input array.
For each element, add a new property to the months property of the results object, whose key is the value of the month property from the element, and whose value is the value of the total property from the element.
Return the result.
If you have specific questions about any of those steps, you can research it further, or ask, such as:
How do I create a new array, with an object inside?
How do I loop through the elements of an array?
How do I retrieve a property from an object?
How do I add a new key/value pair to an object?
How do I return the result?
If you are unfamiliar with any of the terms used above--such as array, object, property, key, value, or element--research them and make sure you know what they mean. Knowing and using correct terminology is the first step to successful programming!
When converting your algorithm into JS, write it step by step, and test it at each phase. For instance, start with a version which doesn't loop over the input at all, and make sure it produces a correct output of [{category: "Amazon", month: {}}]. Walk though your code in the debugger at this and each following step--if you don't know how to use the debugger, learning that should be your first priority! If you want to check a little bit of syntax, to make sure it does what you think, just try it out by typing it into the console. If you don't know what the console is, learning that should be another top priority.
All the above assumes that you've got a single Amazon category. If you are going to have multiple categories, and want multiple objects (one for each) in your output array, then start over from the top and write the algorithm and pseudo-code which can handle that.
Could not find a clear explanation of how to achieve this. Does JS have a straight forward method for taking the entire column from a grid and populating an array with one cell value per array element. I do know the value of each cell. But I want to make an array of all the individual cell values. I am relatively new to JS and thought it might be wiser to ask here than to go on mashing code together seeing no results.
Thank you so much, Luxy
For example,
My cell value is in params.data["Bug Feature"] // which prints each value 0, 13, text, text, 0...
What I want is to make an array of the single values to an array.
I didn't mean to get a full implementation. I just wanted to know the right way. This is what I am doing currently. But it is making each cell value an array which is not what I am looking for.
var sortBUGFeatures = jQuery.makeArray(params.data["Bug Feature"]);
i did it in jQuery but I thought JS would be little simpler for me
I have a table (in a RethinkDB database) that has a bunch of documents with the field VIN0. This field almost always stores numbers, as intended.
I had some data corruption recently where there are some strings in place of numbers for the field VIN0. Queries I was using to manipulate this data now return the error: "e: Expected type NUMBER but found STRING in:"
I'd like to filter for the strings, but I can't seem to find them. Is there a way to use something like Number.isInteger() to filter out these items within RethinkDB?
Thanks!
You can use typeOf to find type of a field, or a element. Let's say you want to filter document with VIN0 is a number
r.db('db').table('table').filter(r.row('VIN0').typeOf().eq('NUMBER'))
You can also try to correct problem by using coereTo to convert string to number.
r.db('db').table('table')
.filter(r.row('VIN0').typeOf().eq('STRING'))
.update({VIN0: r.row('VIN0').coerceTo('NUMBER')})
Hope this helps.
I have a pretty big array of JSON objects (its a music library with properties like artist, album etc, feeding a jqgrid with loadonce=true) and I want to implement lucene-like (google-like) query through whole set - but locally, i.e. in the browser, without communication with web server. Are there any javascript frameworks that will help me?
Go through your records, to create a one time index by combining all search
able fields in a single string field called index.
Store these indexed records in an Array.
Partition the Array on index .. like all a's in one array and so on.
Use the javascript function indexOf() against the index to match the query entered by the user and find records from the partitioned Array.
That was the easy part but, it will support all simple queries in a very efficient manner because the index does not have to be re-created for every query and indexOf operation is very efficient. I have used it for searching up to 2000 records. I used a pre-sorted Array. Actually, that's how Gmail and yahoo mail work. They store your contacts on browser in a pre-sorted array with an index that allows you to see the contact names as you type.
This also gives you a base to build on. Now you can write an advanced query parsing logic on top of it. For example, to support a few simple conditional keywords like - AND OR NOT, will take about 20-30 lines of custom JavaScript code. Or you can find a JS library that will do the parsing for you the way Lucene does.
For a reference implementation of above logic, take a look at how ZmContactList.js sorts and searches the contacts for autocomplete.
You might want to check FullProof, it does exactly that:
https://github.com/reyesr/fullproof
Have you tried CouchDB?
Edit:
How about something along these lines (also see http://jsfiddle.net/7tV3A/1/):
var filtered_collection = [];
var query = 'foo';
$.each(collection, function(i,e){
$.each(e, function(ii, el){
if (el == query) {
filtered_collection.push(e);
}
});
});
The (el == query) part of course could/should be modified to allow more flexible search patterns than exact match.