JSON parser doesn't working properly data mismatched [duplicate] - json

I'm passing back a list of approved tweets from a webserver in JSON format. When I go to the URL: http://localhost:8000/showtweets/?after_id=354210796420608003 in my browser I get the following JSON:
[{
"date": "2013-07-08T12:10:09",
"text": "#RaspberryPi ist auf dem Weg :-)",
"author_pic_url": "http://a0.twimg.com/profile_images/1315863231/twitter_normal.jpg",
"id": 354210796420608004,
"author": "switol"
}]
Which has an id of: 354210796420608004.
When I make a GET call from Javascript, the number changes:
function TweetUpdater() {
}
TweetUpdater.latest_id = 0;
TweetUpdater.undisplayed_tweets = new Array();
TweetUpdater.prototype.get_more_tweets = function () {
// var since_id = parseFloat(TweetUpdater.get_latestlatest_id;
// alert(since_id);
var get_tweets_url = "/showtweets/?after_id="+TweetUpdater.latest_id;
$.get(get_tweets_url, function (tweets) {
if (tweets.length > 0) {
/////////////////////////////////////////////////////////
alert(tweets[0].id+", "+ tweets[0].text); <<<<< THIS LINE
/////////////////////////////////////////////////////////
TweetUpdater.latest_id = tweets[0].id;
for (var i = 0; i < tweets.length; i++) {
TweetUpdater.undisplayed_tweets.push(tweets[i]);
}
}
}, "json");
};
This code alerts: 354210796420608000, #RaspberryPi ist auf dem Weg :-)
354210796420608004 != 354210796420608000
Very odd.

No, not very odd. JS represents all numbers as double, and with growing integers you loose precision at some point. See What is JavaScript's highest integer value that a Number can go to without losing precision? for details.
To solve the problem, simply make the id a string - you're not doing calculations with it anyway. You'll have to do that in the original JSON though, otherwise the precision loss happens at JSON.parse already.

Try using id_str instead of id while using twitter API, It should work. see this https://dev.twitter.com/discussions/11284.

Related

Is there a simple way to have a local webpage display a variable passed in the URL?

I am experimenting with a Firefox extension that will load an arbitrary URL (only via HTTP or HTTPS) when certain conditions are met.
With certain conditions, I just want to display a message instead of requesting a URL from the internet.
I was thinking about simply hosting a local webpage that would display the message. The catch is that the message needs to include a variable.
Is there a simple way to craft a local web page so that it can display a variable passed to it in the URL? I would prefer to just use HTML and CSS, but adding a little inline javascript would be okay if absolutely needed.
As a simple example, when the extension calls something like:
folder/messageoutput.html?t=Text%20to%20display
I would like to see:
Message: Text to display
shown in the browser's viewport.
You can use the "search" property of the Location object to extract the variables from the end of your URL:
var a = window.location.search;
In your example, a will equal "?t=Text%20to%20display".
Next, you will want to strip the leading question mark from the beginning of the string. The if statement is just in case the browser doesn't include it in the search property:
var s = a.substr(0, 1);
if(s == "?"){s = substr(1);}
Just in case you get a URL with more than one variable, you may want to split the query string at ampersands to produce an array of name-value pair strings:
var R = s.split("&");
Next, split the name-value pair strings at the equal sign to separate the name from the value. Store the name as the key to an array, and the value as the array value corresponding to the key:
var L = R.length;
var NVP = new Array();
var temp = new Array();
for(var i = 0; i < L; i++){
temp = R[i].split("=");
NVP[temp[0]] = temp[1];
}
Almost done. Get the value with the name "t":
var t = NVP['t'];
Last, insert the variable text into the document. A simple example (that will need to be tweaked to match your document structure) is:
var containingDiv = document.getElementById("divToShowMessage");
var tn = document.createTextNode(t);
containingDiv.appendChild(tn);
getArg('t');
function getArg(param) {
var vars = {};
window.location.href.replace( location.hash, '' ).replace(
/[?&]+([^=&]+)=?([^&]*)?/gi, // regexp
function( m, key, value ) { // callback
vars[key] = value !== undefined ? value : '';
}
);
if ( param ) {
return vars[param] ? vars[param] : null;
}
return vars;
}

How do i parse the KairosSDK JSON recognise response in Swift?

For those who don't know what the Kairos SDK is, it's basically a facial recognition api.
When you give it an image, it will tell you who if they can match you with someone in the database.
When i give it an image; the api sends me back this response:
[images: (
{
attributes = {
gender = {
confidence = "80%";
type = F;
};
};
candidates = (
{
"enrollment_timestamp" = 1436883322;
face3rd = "0.988351106643677";
},
{
"enrollment_timestamp" = 1436883214;
hi = "0.94137054681778";
},
{
"enrollment_timestamp" = 1436883132;
hi = "0.94137054681778";
}
);
time = "6.43676";
transaction = {
confidence = "0.988351106643677";
"distance_apart" = "0.046980559825897";
"gallery_name" = test1;
height = 482;
"matching_threshold" = "0.4";
"next_subject" = hi;
"next_subject_confidence" = "0.94137054681778";
"simularity_threshold" = "0.1";
status = success;
subject = face3rd;
topLeftX = 148;
topLeftY = 92;
width = 482;
};
}
)]
What i have done is put three images in the database and have called each of them respectively, face3rd, hi, hi (sorry for the two hi's)
I have been trying to parse the names and the number next to it for soo long, i can get around the 6 second response time.
The reason i have not been able to get the names is because, as you can see, i don't know what to tell Swift to look for. The image name changes depending on who i get back.
I don't know if i've explained my situation, bestly, but if you look at the response. The parts that say:
face3rd = "0.988351106643677";
hi = "0.94137054681778";
hi = "0.94137054681778";
I need the information on both sides of the equal sign.
Thank you for your help and apologise, if reading it was pedantic or you felt like their was a lot of repetion.
Thanks!
Yes, it is poorly formatted JSON that we are returning. We will fix it in an upcoming version of the API (no release date at this time..sorry).
If all you need is the closest match, you can just access the subject variable directly and ignore the candidates array.
Otherwise, you would need to parse the candidates array manually unfortunately. I'm not sure how to do that in Swift.

Can Microsoft Translator answer "does a word exist" queries?

I want to know if the API can do something like this:
I send a word in an predetermined language
API answer if the word exist in that language.
To add some context to the question, the idea is to develop a Scrabble like game, and I'm investigating a method to detect valid words, for all (or most common) languages that is.
I've already asked for a solution in one of their forums, but they are kind of dead.
I tested the MS translator service.
var result = MST.TranslateText("xyz", "en", "de"); // custom routine that calls MS service
var result2 = MST.TranslateText("dog", "en", "de");
var result2 = MST.TranslateText("sdfasfgd", "en", "de");
Result = XYZ // source xyz
Result2 = Hund // source dog
Result3 = sdfasfgd // sdfasfgd
Looks like when not found or a translation is not possible the string
is returned untouched.
The only strange behavior i've noted is conversion to uppercase for Some 3 letter scenarios that
arent obvious TLAs in either langauge.
public string TranslateText(string sourceText, string fromLang, string toLang) {
var httpRequestProperty = GetAuthorizationRequestHeader();
var msTransClient = new TranslatorService.LanguageServiceClient();
// Creates a block within which an OperationContext object is in scope.
using (var scope = new OperationContextScope(msTransClient.InnerChannel))
{
OperationContext.Current.OutgoingMessageProperties[HttpRequestMessageProperty.Name] = httpRequestProperty;
//Keep appId parameter blank as we are sending access token in authorization header.
var translationResult = msTransClient.Translate("", sourceText, fromLang, toLang, "text/plain", "");
return translationResult;
}
}

Query a backbone collection (or json) from a Filter model (or json)

I'm trying to render a google map from data I have in a LocationCollection.
Users will define filterParameters in a Model, here is the JSON from a filter
var filter = {
"id_ref_type_category":[2,4],
"pricemin":5,
"pricemax":15,
"distmin":10, // meters
"distmax":150 // meters
}
I need to query my collection, here is a sample of json I have for my location
var location = [
{
"id":"1",
"name":"Sushi 1",
"price_min":"10",
"price_max":"20",
"price_avg":"15",
"id_ref_type_category":"1",
"latitude":"48.863831",
"longitude":"2.356215"
},
{
"id":"2",
"description":"Miam ",
"price_min":"15",
"price_max":"35",
"price_avg":"25",
"id_ref_type_category":"4",
"latitude":"48.864269",
"longitude":"2.355153"
},
{
"id":"3",
"name":"Restaurant 1",
"price_min":"5",
"price_max":"20",
"price_avg":"12.5",
"street_number":"60",
"id_ref_type_category":"1",
"latitude":"48.863407",
"longitude":"2.350938"
},
{
"id":"4",
"name":"Chez gigi",
"price_min":"0",
"price_max":"17",
"price_avg":"8.5",
"id_ref_type_category":"2",
"latitude":"48.861824",
"longitude":"2.350901"
}
]
Regarding to my filter parameter, i am looking for
a location with a id_ref_type_category equal 2 OR 4
a location with an average price around 5 and 15
a location within a distance around 10 and 150 (it's in meters) (if user allow geolocation)
I can calculate the distance from my position to the location with this js function from geocoding http://www.geodatasource.com/developers/javascript
I have looked for backbone collection filtering but didn't find a lot, I have looked for json query systems, but couldn't find any stuff.
I takes any suggestions.
How about applying a underscore filter for all the attributes like in here:
http://jsfiddle.net/cnDeu/1/
I have relaxed a bit your filter object so that a location makes it through.
Essentially the filter looks like this:
var filtered = loc.filter(function (el) {
var dist = distance(el.get('latitude'), el.get('longitude'),
position.latitude, position.longitude, 'K') / 1000;
return ((el.get('id') == filter.id_ref_type_category[0]) ||
(el.get('id') == filter.id_ref_type_category[1])) &&
el.get('price_avg') >= filter.pricemin &&
el.get('price_avg') <= filter.pricemax &&
dist >= filter.distmin &&
dist <= filter.distmax;
});

What's the fastest way to search a very long list of words for a match in actionscript 3?

So I have a list of words (the entire English dictionary).
For a word matching game, when a player moves a piece I need to check the entire dictionary to see if the the word that the player made exists in the dictionary. I need to do this as quickly as possible. simply iterating through the dictionary is way too slow.
What is the quickest algorithm in AS3 to search a long list like this for a match, and what datatype should I use? (ie array, object, Dictionary etc)
I would first go with an Object, which is a hash table (at least, storage-wise).
So, for every word in your list, make an entry in your dictionary Object and store true as its value.
Then, you just have to check if a given word is a key into your dictionary to know whether the word the user has choosen is valid or not.
This works really fast in this simple test (with 10,000,000 entries):
var dict:Object = {};
for(var i:int = 0; i < 10000000; i++) {
dict[i] = true;
}
var btn:Sprite = new Sprite();
btn.graphics.beginFill(0xff0000);
btn.graphics.drawRect(0,0,50,50);
btn.graphics.endFill();
addChild(btn);
btn.addEventListener(MouseEvent.CLICK,checkWord);
var findIt:Boolean = true;
function checkWord(e:MouseEvent):void {
var word:String;
if(findIt) {
word = "3752132";
} else {
word = "9123012456";
}
if(dict[word]) {
trace(word + " found");
} else {
trace(word + " not found");
}
findIt = !findIt;
}
It takes a little longer to build the dictionary, but lookup is almost instantaneous.
The only caveat is that you will have to consider certain keys that will pass the check and not necessarily be part of your words list. Words such as toString, prototype, etc. There are just a few of them, but keep that in mind.
I would try something like this with your real data set. If it works fine, then you have a really easy solution. Go have a beer (or whatever you prefer).
Now, if the above doesn't really work after testing it with real data (notice I've build the list with numbers cast as strings for simplicity), then a couple of options, off the top of my head:
1) Partition the first dict into a set of dictionaries. So, instead of having all the words in dict, have a dictionary for words that begin with 'a', another for 'b', etc. Then, before looking up a word, check the first char to know where to look it up.
Something like:
var word:String = "hello";
var dictKey:String = word.charAt(0);
// actual check
if(dict[dictKey][word]) {
trace("found");
} else {
trace("not found");
}
You can eventually repartition if necessary. I.e, make dict['a'] point to another set of dictionaries indexed by the first two characters. So, you'll have dict['a']['b'][wordToSearch]. There are a number of possible variations on this idea (you'd also have to come up with some strategy to cope with words of two letters, such as "be", for instance).
2) Try a binary search. The problem with it is that you'll first have to sort the list, upfront. You have to do it just once, as it doesn't make sense to remove words from your dict. But with millions of words, it might be rarther intensive.
3) Try some fancy data structures from open source libraries such as:
http://sibirjak.com/blog/index.php/collections/as3commons-collections/
http://lab.polygonal.de/ds/
But again, as I said above, I'd first try the easiest and simpler solution and check if it works against the real data set.
Added
A simple way to deal with keywords used for Object's built-in properties:
var dict:Object = {};
var keywordsInDict:Array = [];
function buildDictionary():void {
// let's assume this is your original list, retrieved
// from XML or other external means
// it contains "constructor", which should be dealt with
// separately, as it's a built-in prop of Object
var sourceList:Array = ["hello","world","foo","bar","constructor"];
var len:int = sourceList.length;
var word:String;
// just a dummy vanilla object, to test if a word in the list
// is already in use internally by Object
var dummy:Object = {};
for(var i:int = 0; i < len; i++) {
// also, lower-casing is a good idea
// do that when you check words as well
word = sourceList[i].toLowerCase();
if(!dummy[word]) {
dict[i] = true;
} else {
// it's a keyword, so store it separately
keywordsInDict.push(word);
}
}
}
Now, just add an extra check for built-in props in the checkWords function:
function checkWord(e:MouseEvent):void {
var word:String;
if(findIt) {
word = "Constructor";
} else {
word = "asdfds";
}
word = word.toLowerCase();
var dummy:Object = {};
// check first if the word is a built-in prop
if(dummy[word]) {
// if it is, check if that word was in the original list
// if it was present, we've stored it in keywordsInDict
if(keywordsInDict.indexOf(word) != -1) {
trace(word + " found");
} else {
trace(word + " not found");
}
// not a built-in prop, so just check if it's present in dict
} else {
if(dict[word]) {
trace(word + " found");
} else {
trace(word + " not found");
}
}
findIt = !findIt;
}
This isn't specific to ActionScript, but a Trie is a suitable data structure for storing words.