I know the method to find the middle element in singly linked list by going through it only once.
Is there some way to find the Mean of the elements in a list?
Based on your comments I suppose you are asking about arithmetic mean (http://en.wikipedia.org/wiki/Mean#Arithmetic_mean_.28AM.29 )
Also if you know how many elements are there you can get rid of count.
Node current = root;
double sum = 0;
int count = 0;
while (current != null) {
sum += current.el;
count++;
current = current.next;
}
System.out.println(sum/count);
Related
My current table looks like this:
Status
Draft
Pending
Complete
I want to sort them based on the value of the cells. Is there a way to do that? I've only been able to sort them using this code:
onChange(status: string){
const sortState: Sort = {active: status, direction: 'desc'};
this.sort.active = sortState.active;
this.sort.direction = sortState.direction;
this.sort.sortChange.emit(sortState);
}
But I want to sort using the values of the status themselves since I'd want to create a button which when click sorts starting from complete or draft or pending.
I'm a little confused by your question, but I think I understand what you're asking.
You're going to want to convert your values into an array and then use the .sort() function. So, assuming you have an array of your cells, we can call that let array = Cell[], you can then access the status of the cells like this:
sortCells(){
let array = Cell[]; // here we're assuming there is already a cell type and a cell.active parameter, like shown in your example.
let possibleValues = ["Draft","Pending","Complete"]; // easier way to compare two values
array.sort((a,b)=>{
let aIndex = possibleValues.indexOf(a.active); // index of gets the location of the element in an array
let bIndex = possibleValues.indexOf(b.active);
if(a > b){
return -1;
} else if(b > a){
return 1;
}else{
return 0; // they are equal
}
})
}
You can read more about sort here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort
I am trying to count the number of rows in an advanceddatagrid
I need a function which could count all item with or without filterFunction.
I tried some solution but none works. The best that I found, is to expand all items and use a cursor for looping.
But, when we have a lot of data, expanding all is not a good solution.
Do you have an idea on how to do that ?
Thank you
The only way I came up was investigating dataProvider
// current not expanded data row lenght
grid.dataProvider.lenght;
// expanded length
// I assume you use xml as your data provider
// then you can count it like this
xmlListTotalSize(new XMLList(grid.dataProvider.source.source));
// or with casts
xmlListTotalSize(new XMLList((IHierarchicalCollectionView(view.grid.dataProvider).source as HierarchicalData).source));
and xmllist traversal function might look something like this:
private static function xmlListTotalSize(x:XMLList):int
{
var i:int = x.length();
for each(var xChild:XML in x.children())
i += xmlListTotalSize(xChild.children());
return i;
}
I have a set of values that are generated dynamically with a foreach loop, how can I add these into one value?
For instance, say I have a site where each node has a number associated with it. How can I add all these numbers together? So far I've figured it'd be something similar to the following, where the value of 'node.aNumberValue' is added to the next one, and so on:
#foreach (var x in nodes){
var total = node.aNumberValue + node.aNumberValue (etc...);
<p>#total</p>
}
This is what you want, I think:
int total = 0;
#foreach (var x in nodes)
{
total += x.aNumberValue;
}
<p>#total</p>
Or even better, just:
<p>#nodes.Sum(x => x.aNumberValue)</p>
Introduction:
I have an AdvancedDataGrid displaying hierarchical data illustrated by the image below:
The branch nodes "Prosjekt" and "Tiltak" display the sum of the leaf nodes below.
Problem: I want the root node "Tavle" to display the total sum of the branch nodes below. When i attempted to do this by adding the same SummaryRow the sum of the root node was not calculcated correctly(Every node's sum was calculated twice).
dg_Teknikktavles = new AutoSizingAdvancedDataGrid();
dg_Teknikktavles.sortExpertMode="true";
dg_Teknikktavles.headerHeight = 50;
dg_Teknikktavles.variableRowHeight = true;
dg_Teknikktavles.addEventListener(ListEvent.ITEM_CLICK,dg_TeknikktavlesItemClicked);
dg_Teknikktavles.editable="false";
dg_Teknikktavles.percentWidth=100;
dg_Teknikktavles.minColumnWidth =0.8;
dg_Teknikktavles.height = 1000;
var sumFieldArray:Array = new Array(context.brukerList.length);
for(var i:int = 0; i < context.brukerList.length; i++)
{
var sumField:SummaryField2 = new SummaryField2();
sumField.dataField = Ressurstavle.ressursKey + i;
sumField.summaryOperation = "SUM";
sumFieldArray[i] = sumField;
}
var summaryRow:SummaryRow = new SummaryRow();
summaryRow.summaryPlacement = "group";
summaryRow.fields = sumFieldArray;
var summaryRow2:SummaryRow = new SummaryRow();
summaryRow2.summaryPlacement = "group";
summaryRow2.fields = sumFieldArray;
var groupField1:GroupingField = new GroupingField();
groupField1.name = "tavle";
//groupField1.summaries = [summaryRow2];
var groupField2:GroupingField = new GroupingField();
groupField2.name = "kategori";
groupField2.summaries = [summaryRow];
var group:Grouping = new Grouping();
group.fields = [groupField1, groupField2];
var groupCol:GroupingCollection2 = new GroupingCollection2();
groupCol.source = ressursTavle;
groupCol.grouping = group;
groupCol.refresh();
Main Question: How do i get my AdvancedDataGrid's (dg_Teknikktavles) root node "Tavle" to correctly display the sum of the two branch nodes below?
Side Question: How do i add a red color to the numbers of the root node's summary row that exceed 5? E.g the column displaying 8 will exceed 5 in the root node's summary row, and should therefore be marked red
Thanks in advance!
This is a general answer, without code examples, but I had to do the same just couple of days ago, so my memory is still fresh :) Here's what I did:
Created a class A to represent an item renderer data, extended it from Proxy (I had field names defined at run time), and let it contain a collection of values as it's data member. Once accessed through flash_proxy::getPropery(fieldName) it would find a corresponding value in the data member containing the values and return it. Special note: implement IUID, just do it, it'll save you couple of days of frustration.
Extended A in B, added a children property containing ArrayCollection of A (don't try to experiment with other collection types, unless you want to find yourself examining tons of framework code, trust me, it's ugly and is impossible to identify as interesting). Let B override flash_proxy::getPropery - depending of your compiler this may, or may not be possible, if not possible - call some function from A.flash_proxy::getPropery() that you can override in B. Let this function query every instance of A, which is a child of B, asking the same thing, as DataGrid itself would, when building item renderers - this way you would get the total.
When creating a data provider. Create an ArrayCollection of B (again, don't try to experiment with other collections--unless you are ready for lots of frustration). Create Hierarchical data that uses this array collection as a source.
Colors - that's what you use item renderers for, just look up any tutorial on using item renderers, that must be pretty basic.
In case someone else has the same problem:
The initial problem that everything was summed twice, was the result of using the same Array of SummaryField2 (sumFieldArray in the code) for both grouping fields(GropingField2 tavle and kategori)
The Solution to the main question: was to create a new array of summaryfields for the root node(in my intial for loop):
//Summary fields for root node
var sumFieldRoot:SummaryField2 = new SummaryField2();
sumFieldRoot.dataField = Ressurstavle.ressursKey + i;
sumFieldRoot.summaryOperation = "SUM";
sumFieldArrayRoot[i] = sumFieldRoot;
Answer to the side question:
This was pretty much as easy as pointed out by wvxyw. Code for this solution below:
private function summary_styleFunction(data:Object, col:AdvancedDataGridColumn):Object
{
var output:Object;
var field:String = col.dataField;
if ( data.children != null )
{
if(data[field] >5){
output = {color:0xFF0000, fontWeight:"bold"}
}
else {
output = {color:0x006633, fontWeight:"bold"}
}
//output = {color:0x081EA6, fontWeight:"bold", fontSize:14}
}
return output;
}
Actually I've parsed a website using htmlparser and I would like to find a specific value inside the parsed object, for example, a string "$199", and keep tracking that element(by periodic parsing) to see the value is still "$199" or has changed.
And after some painful stupid searching using my eyes, I found the that string is located at somewhere like this:
price = handler.dom[3].children[3].children[3].children[5].children[1].
children[3].children[3].children[5].children[0].children[0].raw;
So I'd like to know whether there are methods which are less painful? Thanks!
A tree based recursive search would probably be easiest to get the node you're interested in.
I've not used htmlparser and the documentation seems a little thin, so this is just an example to get you started and is not tested:
function getElement(el,val) {
if (el.children && el.children.length > 0) {
for (var i = 0, l = el.children.length; i<l; i++) {
var r = getElement(el.children[i],val);
if (r) return r;
}
} else {
if (el.raw == val) {
return el;
}
}
return null;
}
Call getElement(handler.dom[3],'$199') and it'll go through all the children recursively until it finds an element without an children and then compares it's raw value with '$199'. Note this is a straight comparison, you might want to swap this for a regexp or similar?