I'm working on a script where I'm converting a text file "data" to an array of objects and will subsequently join that array to Geojson via a common key "GEOID". In "data" I have two objects STATE_FIP and COUNTY_FIP. Those two combined will create a common key to match "GEOID". I need to concatenate them programmatically. Is there a way to do this easily? Below is a screen shot of "data" Thank you!
Not much info given but...try this:
var additionalProps = {}
data.forEach(obj => {
geoid = obj.STATE_FIP + obj.COUNTY_FIP
additionalProps[geoid] = obj
})
var updatedGeoJson = {
"type": "FeatureCollection",
"features": []
};
oldGeoJson.features.forEach(x => {
geoid = x.properties.GEOID
newProps = {...x.properties, ...additionalProps[geoid]}
x.properties = newProps
updatedGeoJson.features.push(x)
})
Related
Newbie here and this is a project I'm building to learn. I'm going around in circles so forgive my ignorance please. I'm now not even sure that what I want to do is possible. I also understand that there are probably better ways to achieve my ultimate goal but this is what I have.
I have an array that includes some user input.
"participants": [ {
"name": "Cristina",
"email": "cristina#gmail",
"yourPerson": "Richard",
"spouseEmail": "Richard#gmail" } ] }
I want to pull the "name" and "youPerson" values and use them as a key:value pair. So name would be the key and yourPerson would be the value.
I thought I could use a forEach but no matter what I do I either get an undefined array or I copy the entire array, not just those two fields.
here is my code at the moment:
participantArray = [];
namePlusSpouseArray = [];
submitParticipant() {
this.participantArray.push(this.participantForm.value);
console.log(this.participantArray)
this.createNamePlusSpouseArray();
}
createNamePlusSpouseArray() {
this.participantArray.forEach(name => {
this.namePlusSpouseArray.push(this.participantArray[name]);
console.log(this.namePlusSpouseArray)
});
}
Not sure if you want a result array of key value pairs, or you want 1 object/map/dictionary/lookup of name -> youPerson
Assuming you want an array containing key value pairs, you can use map
this.namePlusSpouseArray = this.participantArray.map(participant => ({
[participant.name]: participant.youPerson
});
If you want a lookup of name -> youPerson, the "namePlusSpouseArray" shouldn´t be an array but instead just an object
namePlusSpouseLookup = {};
this.participantArray.forEach(participant => {
this.namePlusSpouseLookup[participant.name] = participant.youPerson;
});
The simplest solution is:
const participantArray = {
"participants": [ { "name": "Cristina", "email": "cristina#gmail", "yourPerson": "Richard", "spouseEmail": "Richard#gmail" } ] };
const createPair = participants => {
return participants.map(participant =>
({ [participant.name]: participant.yourPerson}))
}
console.log(createPair(participantArray.participants));
I am getting a JSON object from Firebase. I am trying to convert it into an array of objects.
I can solve this by getting childs from Firebase one-by-one and add them into array however, that is not a good practice for my case.
The format of JSON object is as following:
key: {
id1: {some stuff here},
id2: {some other stuff},
...
}
Now what I want to get from this JSON object is :
arrayName: [
{id1:{some stuff here},
id2:{some other stuff}
]
Hope my description if fully understandable.
Any help would be appreciated
This is just plain javascript, it has nothing to do with react native. By the way, you can use Object.keys to get an array with all the keys, then map the strings as objects:
const x = {foo: 11, bar: 42};
const result = Object.keys(x).map(key => ({[key]: x[key]}));
console.log(result);
This code worked for me.
const JSONString = res.data;
object = JSON.parse(JSONString);
array = Object.keys(object).map(function(k) {
return object[k];
});
Where res.data is the response I am getting from an api
Using Object.entries, you can avoid the extra hash lookup on every item.
const x = { foo: 11, bar: 42 };
const result = Object.entries(x).map(([key, val]) => ({
[key]: val
}));
console.log(result);
"name": [
{
"name": "test1"
},
{
"name": "test2"
},
{
"name": "test3"
},
{
"name": "test1"
},
]
I have the above created by nodejs. During array push, I would like to remove duplicated arrays from the list or only push the name array if the individual array does not exist.
I have tried below codes but it changes the array.
var new = [];
for (var i =0;i<name.length;i++){
new['name'] = name[i].name;
}
The easiest way is probably with Array.prototype.reduce. Something along these lines, given your data structure:
obj.name = Object.values(obj.name.reduce((accumulator, current) => {
if (!accumulator[current.name]) {
accumulator[current.name] = current
}
return accumulator
}, {}));
The reduce creates an object that has keys off the item name, which makes sure that you only have unique names. Then I use Object.values() to turn it back into a regular array of objects like in your data sample.
the solution can be using temp Set;
const tmpSet = new Set();
someObj.name.filter((o)=>{
const has = tmpSet.has(o.name);
tmp.add(o.name);
return has;
});
the filter function iterating over someObj.name field and filter it in place if you return "true". So you check if it exists in a tmp Set & add current value to Set to keep track of duplicates.
PS: new is a reserved word in js;
This should do it
const names = ['John', 'Paul', 'George', 'Ringo', 'John'];
let unique = [...new Set(names)];
console.log(unique); // 'John', 'Paul', 'George', 'Ringo'
https://wsvincent.com/javascript-remove-duplicates-array/
i am trying to read JSON into different arrays using HttpClient for the use in Echarts, but since i am a newbie i couldn't find how to fill JSON into the different arrays.
the part code i used so far was:
....
label: Array<any>;
data: Array<any>;
tooltip: Array<any>;
constructor(private http: HttpClient) {
this.getJSON().subscribe(data => {
this.data=data.data;
this.label=data.label;
this.tooltip=data.tooltip;
console.log(data)
});
}
public getJSON(): Observable<any> {
return this.http.get("./assets/JSONData/TeamProgress.json")
}
the JSON file is formatted like this:
[{"label":"0","data":"0","tooltip":"0"},
{"label":"1","data":"-1","tooltip":" tooltip1"},
{"label":"2","data":"-1","tooltip":" tooltip2"},
...etc
i want to be able to get all labels of JSON in one array, and all data in another array, and all tooltips in a third array.
it would be great if you can help me.
thanks
First the result of that file should be a valid JSON structure aka (an object with key-values) you can group the array under a key called per example result
{
"result": [
{"label":"0","data":"0","tooltip":"0"},
{"label":"1","data":"-1","tooltip":" tooltip1"},
{"label":"2","data":"-1","tooltip":" tooltip2"},
//....Etc
]
}
Then you can access the data and filter it using map as below:
this.getJSON().subscribe((data:any) => {
this.label = data.result.map(element =>
// if you want to return an array of objects
{return {"label": element.label}}
// or if you want to return the raw values in an array, just do
element.label
});
this.data = data.result.map(element => {
return {"data": element.data}
});
this.tooltip = data.result.map(element => {
return {"tooltip": element.tooltip}
})
})
I have two arrays that I want to merge together to one array of objects...
The first array is of dates (strings):
let metrodates = [
"2008-01",
"2008-02",
"2008-03",..ect
];
The second array is of numbers:
let figures = [
0,
0.555,
0.293,..ect
]
I want to merge them to make an object like this (so the array items match up by their similar index):
let metrodata = [
{data: 0, date: "2008-01"},
{data: 0.555, date: "2008-02"},
{data: 0.293, date: "2008-03"},..ect
];
So far I do this like so: I create an empty array and then loop through one of the first two arrays to get the index number (the first two arrays are the same length)... But is there an easier way (in ES6)?
let metrodata = [];
for(let index in metrodates){
metrodata.push({data: figures[index], date: metrodates[index]});
}
The easiest way is probably to use map and the index provided to the callback
let metrodates = [
"2008-01",
"2008-02",
"2008-03"
];
let figures = [
0,
0.555,
0.293
];
let output = metrodates.map((date,i) => ({date, data: figures[i]}));
console.log(output);
Another option is to make a generic zip function which collates your two input arrays into a single array. This is usually called a "zip" because it interlaces the inputs like teeth on a zipper.
const zip = ([x,...xs], [y,...ys]) => {
if (x === undefined || y === undefined)
return [];
else
return [[x,y], ...zip(xs, ys)];
}
let metrodates = [
"2008-01",
"2008-02",
"2008-03"
];
let figures = [
0,
0.555,
0.293
];
let output = zip(metrodates, figures).map(([date, data]) => ({date, data}));
console.log(output);
Another option is to make a generic map function which accepts more than one source array. The mapping function will receive one value from each source list. See Racket's map procedure for more examples of its use.
This answer might seem the most complicated but it is also the most versatile because it accepts any number of source array inputs.
const isEmpty = xs => xs.length === 0;
const head = ([x,...xs]) => x;
const tail = ([x,...xs]) => xs;
const map = (f, ...xxs) => {
let loop = (acc, xxs) => {
if (xxs.some(isEmpty))
return acc;
else
return loop([...acc, f(...xxs.map(head))], xxs.map(tail));
};
return loop([], xxs);
}
let metrodates = [
"2008-01",
"2008-02",
"2008-03"
];
let figures = [
0,
0.555,
0.293
];
let output = map(
(date, data) => ({date, data}),
metrodates,
figures
);
console.log(output);
If you use lodash, you can use zipWith + ES6 shorthand propery names + ES6 Arrow functions for a one-liner, otherwise see #noami's answer.
const metrodata = _.zipWith(figures, metrodates, (data, date)=> ({ data, date }));