I am trying to compare the items in "item" array and the copyofOpList array to retrieve the data occurrences in copyofOpList
this is my try:
var _deleteUsedElement1 = function(item) {
for (var i = 0; i < item.length-1; i++){
for (var j = 0; j< $scope.copyofOpList.length-1; j++){
if (item[i].operationCode == $scope.copyofOpList[j].code) {
$scope.copyofOpList.splice(j, 1);
} } } };
$scope.compareArrays = function() {
...Get data from web Service
_deleteUsedElement1(item);
}
the copyofOpList array has 14 elements,and the item array has 2 array
but my code deletes only one occurrence (the first),so please how can I correct my code,to retrieve any occurances in the copyofOpList array comparing to the item array
thanks for help
I'd try to avoid looping inside a loop - that's neither a very elegant nor a very efficient way to get the result you want.
Here's something more elegant and most likely more efficient:
var item = [1,2], copyofOpList = [1,2,3,4,5,6,7];
var _deleteUsedElement1 = function(item, copyofOpList) {
return copyofOpList.filter(function(listItem) {
return item.indexOf(listItem) === -1;
});
};
copyofOpList = _deleteUsedElement1(item, copyofOpList);
console.log(copyofOpList);
//prints [3,4,5,6,7]
}
And since I just noticed that you're comparing object properties, here's a version that filters on matching object properties:
var item = [{opCode:1},{opCode:2}],
copyofOpList = [{opCode:1},{opCode:2},{opCode:3},{opCode:4},{opCode:5},{opCode:6},{opCode:7}];
var _deleteUsedElement1 = function(item, copyofOpList) {
var iOpCodes = item.map(function (i) {return i.opCode;});
return copyofOpList.filter(function(listItem) {
return iOpCodes.indexOf(listItem.opCode) === -1;
});
};
copyofOpList = _deleteUsedElement1(item, copyofOpList);
console.log(copyofOpList);
//prints [{opCode:3},{opCode:4},{opCode:5},{opCode:6},{opCode:7}]
Another benefit of doing it in this manner is that you avoid modifying your arrays while you're still operating on them, a positive effect that both JonSG and Furhan S. mentioned in their answers.
Splicing will change your array. Use a temporary buffer array for new values like this:
var _deleteUsedElement1 = function(item) {
var _temp = [];
for (var i = 0; i < $scope.copyofOpList.length-1; i++){
for (var j = 0; j< item.length-1; j++){
if ($scope.copyofOpList[i].code != item[j].operationCode) {
_temp.push($scope.copyofOpList[j]);
}
}
}
$scope.copyofOpList = _temp;
};
var actual = [
{"country":"UK","month":"JAN","SR":"John P","AC":"24","PR":"2","TR":1240},
{"country":"AUSTRIA","month":"JAN","SR":"Brad P","AC":"64","PR":"12","TR":1700},
{"country":"ITALY","month":"JAN","SR":"Gim P","AC":"21","PR":"5","TR":900},
{"country":"UK","month":"FEB","SR":"John P","AC":"14","PR":"4","TR":540},
{"country":"AUSTRIA","month":"FEB","SR":"Brad P","AC":"24","PR":"12","TR":1700},
{"country":"ITALY","month":"FEB","SR":"Gim P","AC":"22","PR":"3","TR":600},
{"country":"UK","month":"MAR","SR":"John P","AC":"56","PR":"2","TR":1440},
{"country":"AUSTRIA","month":"MAR","SR":"Brad P","AC":"24","PR":"12","TR":700},
{"country":"ITALY","month":"MAR","SR":"Gim P","AC":"51","PR":"5","TR":200}
];
var expect = [
{month:"JAN",val: {"UK":"24","AUSTRIA":"64","ITALY":"21"}},
{month:"FEB",val: {"UK":"14","AUSTRIA":"24","ITALY":"22"}},
{month:"MAR",val: {"UK":"56","AUSTRIA":"24","ITALY":"51"}}
];
I have array of objects which i need to reshape for one other work. need some manipulation which will convert by one function. I have created plunker https://jsbin.com/himawakaju/edit?html,js,console,output
Main factors are Month, Country and its "AC" value.
Loop through, make an object and than loop through to make your array
var actual = [
{"country":"UK","month":"JAN","SR":"John P","AC":"24","PR":"2","TR":1240},
{"country":"AUSTRIA","month":"JAN","SR":"Brad P","AC":"64","PR":"12","TR":1700},
{"country":"ITALY","month":"JAN","SR":"Gim P","AC":"21","PR":"5","TR":900},
{"country":"UK","month":"FEB","SR":"John P","AC":"14","PR":"4","TR":540},
{"country":"AUSTRIA","month":"FEB","SR":"Brad P","AC":"24","PR":"12","TR":1700},
{"country":"ITALY","month":"FEB","SR":"Gim P","AC":"22","PR":"3","TR":600},
{"country":"UK","month":"MAR","SR":"John P","AC":"56","PR":"2","TR":1440},
{"country":"AUSTRIA","month":"MAR","SR":"Brad P","AC":"24","PR":"12","TR":700},
{"country":"ITALY","month":"MAR","SR":"Gim P","AC":"51","PR":"5","TR":200}
];
var outTemp = {};
actual.forEach(function(obj){ //loop through array
//see if we saw the month already, if not create it
if(!outTemp[obj.month]) outTemp[obj.month] = { month : obj.month, val: {} };
outTemp[obj.month].val[obj.country] = obj.AC; //add the country with value
});
var expected = []; //convert the object to the array format that was expected
for (var p in outTemp) {
expected.push(outTemp[p]);
}
console.log(expected);
Iterate through array and create new list
var actual = [
{"country":"UK","month":"JAN","SR":"John P","AC":"24","PR":"2","TR":1240},
{"country":"AUSTRIA","month":"JAN","SR":"Brad P","AC":"64","PR":"12","TR":1700},
{"country":"ITALY","month":"JAN","SR":"Gim P","AC":"21","PR":"5","TR":900},
{"country":"UK","month":"FEB","SR":"John P","AC":"14","PR":"4","TR":540},
{"country":"AUSTRIA","month":"FEB","SR":"Brad P","AC":"24","PR":"12","TR":1700},
{"country":"ITALY","month":"FEB","SR":"Gim P","AC":"22","PR":"3","TR":600},
{"country":"UK","month":"MAR","SR":"John P","AC":"56","PR":"2","TR":1440},
{"country":"AUSTRIA","month":"MAR","SR":"Brad P","AC":"24","PR":"12","TR":700},
{"country":"ITALY","month":"MAR","SR":"Gim P","AC":"51","PR":"5","TR":200}
];
var newList =[], val;
for(var i=0; i < actual.length; i+=3){
val = {};
val[actual[i].country] = actual[i]["AC"];
val[actual[i+1].country] = actual[i+1]["AC"];
val[actual[i+2].country] = actual[i+2]["AC"];
newList.push({month: actual[i].month, val:val})
}
document.body.innerHTML = JSON.stringify(newList);
This is the correct code... as above solution will help you if there are 3 rows and these will be in same sequnece.
Here is perfect solution :
var actual = [
{"country":"UK","month":"JAN","SR":"John P","AC":"24","PR":"2","TR":1240},
{"country":"AUSTRIA","month":"JAN","SR":"Brad P","AC":"64","PR":"12","TR":1700},
{"country":"ITALY","month":"JAN","SR":"Gim P","AC":"21","PR":"5","TR":900},
{"country":"UK","month":"FEB","SR":"John P","AC":"14","PR":"4","TR":540},
{"country":"AUSTRIA","month":"FEB","SR":"Brad P","AC":"24","PR":"12","TR":1700},
{"country":"ITALY","month":"FEB","SR":"Gim P","AC":"22","PR":"3","TR":600},
{"country":"UK","month":"MAR","SR":"John P","AC":"56","PR":"2","TR":1440},
{"country":"AUSTRIA","month":"MAR","SR":"Brad P","AC":"24","PR":"12","TR":700},
{"country":"ITALY","month":"MAR","SR":"Gim P","AC":"51","PR":"5","TR":200}
];
var tmpArray = [];
var obj =[];
for(var k=0; k<actual.length; k++){
var position = tmpArray.indexOf(actual[k].month);
if(position == -1){
tmpArray.push(actual[k].month);
val = {};
for(var i=0; i<actual.length; i++){
if(actual[i].month == actual[k].month){
val[actual[i].country] = actual[i]["AC"];
}
}
obj.push({month: actual[k].month, val:val});
}
}
I'm trying to access elements from a JavaScript array:
[["1","John"],["2","Rajan"],["3","Hitesh"],["4","Vin"],["5","ritwik"],["6","sherry"]]
I want to access
1, 2, 3, 4, 5, 6 separately in a variable and John, Rajan, Hitesh, Vin, Ritwik, Sherry separately in a variable.
I tried converting it to a string and split(), but it doesn't work.
this is code i tried
var jArray = <?php echo json_encode($newarray); ?> ;
var nJarr = jArray[0]; nJarr.toString();
var res = nJarr.split(","); var apname = res[0];
alert(apname);
but there's no alert appearing on the screen
If you are open to using Underscore, then it's just
var transposed = _.zip.apply(0, arr);
and the arrays you are looking for will be in transposed[0] and transposed[1].
You can write your own transpose function fairly easily, and it's more compact if you can use ES6 syntax:
transpose = arr => Object.keys(arr[0]).map(i => arr.map(e => e[i]));
>> transpose([["1","John"], ["2","Rajan"], ...]]
<< [[1, 2, ...], ["John", "Rajan", ...]]
If you want an ES5 version, here's one with comments:
function transpose(arr) { // to transpose an array of arrays
return Object.keys(arr[0]) . // get the keys of first sub-array
map(function(i) { // and for each of these keys
arr . // go through the array
map(function(e) { // and from each sub-array
return e[i]; // grab the element with that key
})
))
;
}
If you prefer old-style JS:
function transpose(arr) {
// create and initialize result
var result = [];
for (var i = 0; i < arr[0].length; i++ ) { result[i] = []; }
// loop over subarrays
for (i = 0; i < arr.length; i++) {
var subarray = arr[i];
// loop over elements of subarray and put in result
for (var j = 0; j < subarray.length; j++) {
result[j].push(subarray[j]);
}
}
return result;
}
Do it like bellow
var arr = [["1","John"],["2","Rajan"],["3","Hitesh"],["4","Vin"],["5","ritwik"],["6","sherry"]];
var numbers = arr.map(function(a){return a[0]}); //numbers contain 1,2,3,4,5
var names = arr.map(function(a){return a[1]}); //names contain John,Rajan...
Try this:
var data = [["1","John"],["2","Rajan"],["3","Hitesh"],["4","Vin"],["5","ritwik"],["6","sherry"]];
var IDs = [];
var names = [];
for(i=0; i<data.length; i++)
{
IDs.push(data[i][0]);
names.push(data[i][1]);
}
console.log(IDs);
console.log(names);
Here is the working fiddle.
I need help figuring out how I can loop through the Source Object to get the Output Strings. I currently have some nested for loops but I wind up missing one of the combinations or I get too much. The Number of Categories and Filters will vary
Source Object
var Source = {Cat1:{Filter1:'f1',Filter2:'f2'},
Cat2:{Filter3:'f3',Filter4:'f4'},
Cat3:{Filter5:'f5'}};
Output Strings
Filter1 Filter3 Filter5,
Filter1 Filter4 Filter5,
Filter2 Filter3 Filter5,
Filter2 Filter4 Filter5
Try this, this will return Array of arrays:
function cartesianProduct(paramArray) {
function addTo(curr, args) {
var i, copy,
rest = args.slice(1),
last = !rest.length,
result = [];
for (i = 0; i < args[0].length; i++) {
copy = curr.slice();
copy.push(args[0][i]);
if (last) {
result.push(copy);
} else {
result = result.concat(addTo(copy, rest));
}
}
return result;
}
return addTo([], Array.prototype.slice.call(arguments));
};
var Source = {Cat1:{Filter1:'f1',Filter2:'f2'},
Cat2:{Filter3:'f3',Filter4:'f4'},
Cat3:{Filter5:'f5'}};
// var cats = [];
var filters = [];
for(var c in Source) {
filters.push([]);
for(var f in Source[c])
filters[filters.length - 1].push(f);
}
console.log(cartesianProduct.apply(this || window, filters));
HTH
I have a variable as follows:
var dataset = {
"towns": [
["Aladağ", "Adana", [35.4,37.5], [0]],
["Ceyhan", "Adana", [35.8,37], [0]],
["Feke", "Adana", [35.9,37.8], [0]]
]
};
The variable has a lot of town data in it. How can I extract the first elements of the third ones from the data efficiently? I,e, what will ... be below?
var myArray = ...
//myArray == [35.4,35.8,35.9] for the given data
And what to do if I want to store both values in the array? That is
var myArray = ...
//myArray == [[35.4,37.5], [35.8,37], [35.9,37.8]] for the given data
I'm very new to Javascript. I hope there's a way without using for loops.
On newer browsers, you can use map, or forEach which would avoid using a for loop.
var myArray = dataset.towns.map(function(town){
return town[2];
});
// myArray == [[35.4,37.5], [35.8,37], [35.9,37.8]]
But for loops are more compatible.
var myArray = [];
for(var i = 0, len = dataset.towns.length; i < len; i++){
myArray.push(dataset.towns[i][2];
}
Impossible without loops:
var myArray = [];
for (var i = 0; i < dataset.towns.length; i++) {
myArray.push(dataset.towns[i][2][0]);
}
// at this stage myArray = [35.4, 35.8, 35.9]
And what to do if I want to store both values in the array?
Similar, you just add the entire array, not only the first element:
var myArray = [];
for (var i = 0; i < dataset.towns.length; i++) {
myArray.push(dataset.towns[i][2]);
}
// at this stage myArray = [[35.4,37.5], [35.8,37], [35.9,37.8]]