I am trying to parse data in d3 using the csv function. I am attempting to give each datapoint a new attribute (Region) during processing. Outside the CSV function I defined a function that is supposed to take the datapoint, check to see if the state is Alabama, and if so, assign the Region attribute to a string of either "North" or "South".
var parseRegion = (function(d){
if(d.State === "Alabama"){
return "South";
}
else {
return "North";
}
});
However, when I run the code, every datapoint is assigned a "Region" attribute that is assigned to the function itself. In other words, it is assigned the actual code, rather than the return values. What am I doing wrong??
d3.csv("data.csv").get(function(error,data){
if (error) throw error;
data.forEach(function(d){
d.Deaths = +d.Deaths;
d.Population = +d.Population;
d.Year = parseDate(d.Year);
d.Region = parseRegion;
});
Thanks for any help you can provide. Eventually I will add additional states besides Alabama of course.
Your problem is that you're not calling the parseRegion function that you define.
So you need
d.Region = parseRegion(d);
More generally d3.csv provides a way to parse the data without the use of forEach. You can do the following:
d3.csv("data.csv")
.row(function(d) {
//Code to parse data row by row goes here
})
.get(function(error,data){
//Data is now the whole parsed dataset
});
Related
I would like to reach a specific property of the data that I have returned from my service.
So basically I want to be able to somehow reach $scope.users.name, I know that the users are the objects in the array, but could I reach that specific property in any way? Hopefully the question is clear enough?
$scope.users = [];
UserService.getAll().then(
function (data) {
$scope.users = data;
}, function (err) {
console.log(err);
}
);
I am assuming the data you receive is in the form of an array. If you know the index then you can do
$scope.users[2].name
Where 2 is the index of the object you want to know the name property of.
Or you can try a js function forEach
$scope.users.forEach(function (user) {
console.log(user.name);
});
The function will iterate over all the objects and you can access their properties inside the callback which is passed in.
Hope that is what you're looking for.
I have a standard JSON response in an Angular controller, which returns data.
I am trying to get specific parts of that data, and manipulate it and use the manipulated version within the code.
Currently i have:
$http.get('/json/file.json').success(function(data) {
$scope.results = data;
});
In the JSON, i have data such as this:
"hotels":[
{
"region": "Indian Ocean"
}
]
In my code, i am using ng-repeat to call "hotel in results.hotels" and using "hotel.region".
How do i grab the hotel.region from the data, and remove the space between the words, replace the space with a '_' and make it all lower case so i end up with "indian_ocean". As well as this, how would i then use this within my ng-repeat?
Many thanks..
data.hotels[0].region.replace(" ","_").toLowercase()
Just do...
$scope.results.forEach(function (element) {element.replace(" ","_").toLowercase()});
I figured it out so this can be used in a more general way.
Create a new filter...
app.filter('removeSpaces', function () {
return function (text) {
var str = text.replace(/\s+/g, '_');
return str.toLowerCase();
};
});
Then this can be used site-wide by calling "{{hotel.region | removeSpaces}}".
Thanks to the people who did respond and for their help.
I'm making a todo list. When first entering the item and adding it to the list, the server works great. It takes the parameters that the user selects and passes them into a list on the server that can be viewed by rendering Item.list(), that looks like so:
[{"class":"server.Item","id":1,"assignedTo":"User 1","comments":null,"completed":false,"creator":"User 1","name":"Task 1","priority":"1","type":"Personal"},
{"class":"server.Item","id":2,"assignedTo":"User 2","comments":null,"completed":false,"creator":"User 2","name":"Er","priority":"3","type":"Work"},
{"class":"server.Item","id":3,"assignedTo":"User 1","comments":null,"completed":false,"creator":"User 2","name":"Ga","priority":"1","type":"Work"}]
Now, the user then has the option to edit the task later. On the client side this works fine, but then I need the user to be able to save the new, updated task.
This is my current update function:
def updateList() {
def newItem = Item.findById(request.JSON.id)
newItem.assignedTo = request.JSON.assignedTo
newItem.comments = request.JSON.comments
newItem.completed = request.JSON.completed
newItem.creator = request.JSON.creator
newItem.name = request.JSON.name
newItem.priority = request.JSON.priority
newItem.type = request.JSON.type
newItem.save(flush: true)
render newItem as JSON
}
This doesn't work, however. I get a null pointer exception that says "Cannot set property "assignedTo" on null object. I'm assuming that the findById request is not getting anything for the JSON object, and thus there is no object to assign values to, however I don't know what the problem is considering the items are in fact being put into the Item.list().
This is called with the following JS function on the client side:
$scope.updateList = function() {
angular.forEach($scope.items, function (item) {
// serverList.save({command: 'updateList'}, item);
$http.post('http://localhost:8080/server/todoList/updateList', item)
.success(function(response) {})
.error(function(response) {alert("Failed to update");});
});
};
This might depend on your Grails version, but you should be able to do this:
def update(Item item) {
if (!item) {
// return a 404
} else {
// you should really use a service and not save
// in the controller
itemService.update(item)
respond item
}
}
Grails is smart enough look that item up since there is an ID in the JSON params, and populate the object correctly.
Sort of a work around for anyone else that may need to do this in a basic manner, what I've done that works is clear the list when "Update List" is clicked, then read back in the values that are currently in the client side list.
Grails:
def clearList() {
Item.executeUpdate('delete from Item')
render Item.list()
}
def updateList() {
def newItem = new Item(request.JSON)
newItem.save(flush:true)
render newItem as JSON
}
Javascript:
$scope.updateList = function() { // Update list on the server
serverList.get({command: 'clearList'});
angular.forEach($scope.items, function (item) {
serverList.save({command: 'updateList'}, item);
});
};
I am trying to pass a simple variable value into an HTML file using ember.js. My value is contained within a json file called value.json.
My HTML code is as follows:
<h1>I won {{App.moneyvalue}} today!</h1>
However when I pass the json call via ember, it think that the entire call is a variable:
App = Ember.Application.create({
moneyvalue: function () {
return $.getJSON( "js/value.json", function( data ) {
return data.tot;
});
}
}
And returns the following:
I won function () { return $.getJSON( "js/donors.json", function( data ) { return data.tot; }); } today!
As it seems to think that moneyvalue is a string variable as opposed to a value?
The jSON file is superbasic
{
"tot": 100
}
Where is this going wrong?
you're supplying Handlebars with a function, generally you would use a computed or normal property on the object. In this case you really just shouldn't define it in the application scope either, I'd recommend using an application route (it's the root route of your app).
App.ApplicationRoute = Ember.Route.extend({
model: function(){
return $.getJSON( "js/value.json");
}
});
Then in your handlebars just use
<h1>I won {{tot}} today!</h1>
Here's an example: http://emberjs.jsbin.com/OxIDiVU/576/edit
I would like to know if any better way to create multiple collections fetching from a single big JSON file. I got a JSON file looks like this.
{
"Languages": [...],
"ProductTypes": [...],
"Menus": [...],
"Submenus": [...],
"SampleOne": [...],
"SampleTwo": [...],
"SampleMore": [...]
}
I am using the url/fetch to create each collection for each node of the JSON above.
var source = 'data/sample.json';
Languages.url = source;
Languages.fetch();
ProductTypes.url = source;
ProductTypes.fetch();
Menus.url = source;
Menus.fetch();
Submenus.url = source;
Submenus.fetch();
SampleOne.url = source;
SampleOne.fetch();
SampleTwo.url = source;
SampleTwo.fetch();
SampleMore.url = source;
SampleMore.fetch();
Any better solution for this?
Backbone is great for when your application fits the mold it provides. But don't be afraid to go around it when it makes sense for your application. It's a very small library. Making repetitive and duplicate GET requests just to fit backbone's mold is probably prohibitively inefficient. Check out jQuery.getJSON or your favorite basic AJAX library, paired with some basic metaprogramming as following:
//Put your real collection constructors here. Just examples.
var collections = {
Languages: Backbone.Collection.extend(),
ProductTypes: Backbone.Collection.extend(),
Menus: Backbone.Collection.extend()
};
function fetch() {
$.getJSON("/url/to/your/big.json", {
success: function (response) {
for (var name in collections) {
//Grab the list of raw json objects by name out of the response
//pass it to your collection's constructor
//and store a reference to your now-populated collection instance
//in your collection lookup object
collections[name] = new collections[name](response[name]);
}
}
});
}
fetch();
Once you've called fetch() and the asyn callback has completed, you can do things like collections.Menus.at(0) to get at the loaded model instances.
Your current approach, in addition to being pretty long, risks retrieving the large file multiple times (browser caching won't always work here, especially if the first request hasn't completed by the time you make the next one).
I think the easiest option here is to go with straight jQuery, rather than Backbone, then use .reset() on your collections:
$.get('data/sample.json', function(data) {
Languages.reset(data['Languages']);
ProductTypes.reset(data['ProductTypes']);
// etc
});
If you wanted to cut down on the redundant code, you can put your collections into a namespace like app and then do something like this (though it might be a bit too clever to be legible):
app.Languages = new LanguageCollection();
// etc
$.get('data/sample.json', function(data) {
_(['Languages', 'ProductTypes', ... ]).each(function(collection) {
app[collection].reset(data[collection]);
})
});
I think you can solve your need and still stay into the Backbone paradigm, I think an elegant solution that fits to me is create a Model that fetch the big JSON and uses it to fetch all the Collections in its change event:
var App = Backbone.Model.extend({
url: "http://myserver.com/data/sample.json",
initialize: function( opts ){
this.languages = new Languages();
this.productTypes = new ProductTypes();
// ...
this.on( "change", this.fetchCollections, this );
},
fetchCollections: function(){
this.languages.reset( this.get( "Languages" ) );
this.productTypes.reset( this.get( "ProductTypes" ) );
// ...
}
});
var myApp = new App();
myApp.fetch();
You have access to all your collections through:
myApp.languages
myApp.productTypes
...
You can easily do this with a parse method. Set up a model and create an attribute for each collection. There's nothing saying your model attribute has to be a single piece of data and can't be a collection.
When you run your fetch it will return back the entire response to a parse method that you can override by creating a parse function in your model. Something like:
parse: function(response) {
var myResponse = {};
_.each(response.data, function(value, key) {
myResponse[key] = new Backbone.Collection(value);
}
return myResponse;
}
You could also create new collections at a global level or into some other namespace if you'd rather not have them contained in a model, but that's up to you.
To get them from the model later you'd just have to do something like:
model.get('Languages');
backbone-relational provides a solution within backbone (without using jQuery.getJSON) which might make sense if you're already using it. Short answer at https://stackoverflow.com/a/11095675/70987 which I'd be happy to elaborate on if needed.