I was wondering if someone could help me out.
I have 2 sets of data being returned from an API which i need to chart to a line graph, the problem is i dont know which set of results will come at any given time, so i need something that will be able to chart both sets of the results.
The first set has the following info, ( taken from a var_dump )
'series' => string '[{name: 'Data'}]'
'data_lines' => string '[[[1473731108000,3.4804],[1473731406000,1.7047],[1473731704000,1.7559],[1473732004000,1.2774],[1473732304000,1.9295]]]'
The first number is a timestamp, and the second number is the plot point in GB, and the series name is the series name obviously.
The above set of results only needs one line, the second set of data is an averaging set of results and needs 3 lines, its response is as follows:
'series' => string '[{name: 'Data (average)'},{name: 'Data (maximum)'},{name: 'Data (minimum)'}]'
'data_lines' => string '[[[1473638400000,1.5094]],[[1473638400000,6.7825]],[[1473638400000,1.0546]]]'
and this one obviously has 3 data values for the 3 labels per timestamp.
Any help in getting this going would be greatly appreciated.
This is my sugestion: Create a function that will act like a router for your results. I don't know how you are processing your results (PHP or javascript), BTW:
function chartSelector($data) {
if (count($data['series']) == 3) {
//put the logic to process the averaging set of results here
} else {
//put the logic for the other set here
}
}
This function will direct the processing according to the given set of data :)
Related
so I'm trying to deal with a function but it's looping like crazy and I can't figure out why.
Basically, I want to loop over a json file, retrieve every "average" value and sort it in a new array, so when I call the function ranking(countries[iso].average), it returns the position in the array.
It's actually working but the json file is way bigger, and when I console.log(rank) in the loop, it returns more than 27K messages.
ranking = (n) => {
var rank = [];
if (n) {
for (let iso in countries) {
var newvar = countries[iso].average;
rank.push(newvar);
rank.sort(function(a, b) {
return b - a;
});
}
return rank.indexOf(n) + 1
}
};
{"countries":{"US":{"name":"United States of America","ranking":"","average":13.12,"flag":"https://restcountries.eu/data/usa.svg","altNames":["US","USA"],"reports":1302,"cases":0,"deaths":299692,"recovered":23232,"lat":38,"lng":-97,"deltaCases":2,"deltaDeaths":3,"deltaRecovered":0,"casesPerOneMillion":2,"deathsPerOneMillion":903,"totalTests":22323,"testsPerOneMillion":3434,"population":345},"IN":{"name":"India","ranking":"","average":10.22,"flag":"https://restcountries.eu/data/ind.svg","altNames":["IN","Bhārat"],"reports":1016,"cases":9796992,"deaths":142222,"recovered":9290834,"lat":20,"lng":77,"deltaCases":null,"deltaDeaths":null,"deltaRecovered":646,"casesPerOneMillion":7068,"deathsPerOneMillion":103,"totalTests":151632223,"testsPerOneMillion":109402,"population":1295210000},"RU":{"name":"Russian Federation","ranking":"","average":13.21,"flag":"https://restcountries.eu/data/rus.svg","altNames":["RU","Rossiya"],"reports":1321,"cases":2597711,"deaths":45893,"recovered":2059840,"lat":60,"lng":100,"deltaCases":28585,"deltaDeaths":613,"deltaRecovered":26171,"casesPerOneMillion":17797,"deathsPerOneMillion":314,"totalTests":81564365,"testsPerOneMillion":558804,"population":146599183}}}
Thanks for any help on this
I believe that what you may be trying to do is sort by the field called average for countries in the iso. So you have some lookup called countries and there are ISOs there like I imagine: 'US'. Then Rank is an array of all these countries.
The problem I see is that you have sort happening within the for loop.
The way you explained the problem seems like 2 different steps. One retrieve the average, then AFTER that sort by the average.
If really all you want is the averages in the array: you can do like
const averages = Object.values(countries).map(country => country.average)
That single step will get you all the averages into a single array.
Then next you can sort using the same function you posted. (The key is to brake that into a second loop not a nested loop:
averages.sort((a, b) => b - a)
// now sorted
But in case you wanted to keep the rest of the data you can do that pretty easily as well:
Something more like:
const countriesSortedByAverage = Object.values(countries).sort((a, b) => b.average - a.average)
If you really need the ISO you can also do the same with Object.entries but it might be even easier to provide the iso inside the country Object.
To determine the rank for all countries you can easily add that to (if you wanted) and have that be the principal country Object:
const RANKED_LIST_OF_COUNT = countriesSortedByAverage.map((countryObj, rank) => ({ ...countryObj, rank }))
If you want to further restore it to the CountriesByISO object:
const COUNTRIES_BY_ISO_WITH_RANK = Object.assign({}, ...RANKED_LIST_OF_COUNT.map(country => ({ [country.ISO]: country}))
)
I am working on an app that requires a sync to the server after logging in to get all the activities the user has created and saved to the server. Currently, when the user logs in a getActivity() function that makes an API request and returns a response which is then handled.
Say the user has 4 activities saved on the server in this order (The order is determined by the time of the activity being created / saved) ;
Test
Bob
cvb
Testing
looking at the JSONHandler.getActivityResponse , it appears as though the the results are in the correct order. If the request was successful, on the home page where these activities are to be displayed, I currently loop through them like so;
WebAPIHandler.shared.getActivityRequest(completion:
{
success, results in DispatchQueue.main.async {
if(success)
{
for _ in (results)!
{
guard let managedObjectContext = self.managedObjectContext else { return }
let activity = Activity(context: managedObjectContext)
activity.name = results![WebAPIHandler.shared.idCount].name
print("activity name is - \(activity.name)")
WebAPIHandler.shared.idCount += 1
}
}
And the print within the for loop is also outputting in the expected order;
activity name is - Optional("Test")
activity name is - Optional("Bob")
activity name is - Optional("cvb")
activity name is - Optional("Testing")
The CollectionView does then insert new cells, but it seemingly in the wrong order. I'm using a carousel layout on the home page, and the 'cvb' object for example is appearing first in the list, and 'bob' is third in the list. I am using the following
func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any, at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?)
{
switch (type)
{
case .insert:
if var indexPath = newIndexPath
{
// var itemCount = 0
// var arrayWithIndexPaths: [IndexPath] = []
//
// for _ in 0..<(WebAPIHandler.shared.idCount)
// {
// itemCount += 1
//
// arrayWithIndexPaths.append(IndexPath(item: itemCount - 1, section: 0))
// print("itemCount = \(itemCount)")
// }
print("Insert object")
// walkThroughCollectionView.insertItems(at: arrayWithIndexPaths)
walkThroughCollectionView.reloadData()
}
You can see why I've tried to use collectionView.insertItems() but that would cause an error stating:
Invalid update: invalid number of items in section 0. The number of items contained in an existing section after the update (4) must be equal to the number of items contained in that section before the update (4), plus or minus the number of items inserted or deleted from that section (4 inserted, 0 deleted)
I saw a lot of other answers mentioning how reloadData() would fix the issue, but I'm real stuck at this point. I've been using swift for several months now, and this has been the first time I'm truly at a loss. What I also realised is that the order displayed in the carousel is also different to a separate viewController which is passed the same data. I just have no idea why the results return in the correct order, but are then displayed in an incorrect order. Is there a way to sort data in the collectionView after calling reloadData() or am I looking at this from the wrong angle?
Any help would be much appreciated, cheers!
The order of the collection view is specified by the sort descriptor(s) of the fetched results controller.
Usually the workflow of inserting a new NSManagedObject is
Insert the new object into the managed object context.
Save the context. This calls the delegate methods controllerWillChangeContent, controller(:didChange:at: etc.
In controller(:didChange:at: insert the cell into the collection view with insertItems(at:, nothing else. Do not call reloadData() in this method.
I have a select that I get Json post with http, but I try to sets initially selected index but there is nothing in the list do not select anything. because the json is great.
public AppMainScreen() {
loadLists();
MySelect = new ObjectChoiceField( "Select: ", new Object[0], 3 );
VerticalFieldManager vfm = new VerticalFieldManager(Manager.VERTICAL_SCROLL);
vfm.add(MySelect);
add(vfm);
}
This statement appears wrong to me:
new ObjectChoiceField( "Select: ", new Object[0],3);
The second parameter to this constructor is supposed to be an array of objects whose .toString() method will be used to populate the choices. In this case, you have given it a 0 length array, i.e. no Objects. So there is nothing to choose. And then you have asked it to automatically select the 3rd item, and of course there is no 3rd item.
You should correct the code to actually supply an object array.
One option to make it easy is have your JSON load actually create a String array with one entry per selectable item. Then you use the index selected to identify the chosen item.
The normal result() method described in the documentation appears to load all records immediately. My application needs to load about 30,000 rows, and one at a time, submit them to a third-party search index API. Obviously loading everything into memory at once doesn't work well (errors out because of too much memory).
So my question is, how can I achieve the effect of the conventional MySQLi API method, in which you load one row at a time in a loop?
Here is something you can do.
while ($row = $result->_fetch_object()) {
$data = array(
'id' => $row->id
'some_value' => $row->some_field_name
);
// send row data to whatever api
$this->send_data_to_api($data);
}
This will get one row at the time. Check the CodeIgniter source code, and you will see that they will do this when you execute the result() method.
For those who want to save memory on large result-set:
Since CodeIgniter 3.0.0,
There is a unbuffered_row function,
All the methods above will load the whole result into memory (prefetching). Use unbuffered_row() for processing large result sets.
This method returns a single result row without prefetching the whole result in memory as row() does. If your query has more than one row, it returns the current row and moves the internal data pointer ahead.
$query = $this->db->query("YOUR QUERY");
while ($row = $query->unbuffered_row())
{
echo $row->title;
echo $row->name;
echo $row->body;
}
You can optionally pass ‘object’ (default) or ‘array’ in order to specify the returned value’s type:
$query->unbuffered_row(); // object
$query->unbuffered_row('object'); // object
$query->unbuffered_row('array'); // associative array
Official Document: https://www.codeigniter.com/userguide3/database/results.html#id2
Well, the thing is that result() gives away the entire reply of the query. row() simply fetches the first case and dumps the rest. However the query can still fetched 30 000 rows regardles of which function you use.
One design that would fit your cause would be:
$offset = (int)#$_GET['offset'];
$query = $this-db->query("SELECT * FROM table LIMIT ?, 1", array($offset));
$row = $query->row();
if ($row) {
/* Run api with values */
redirect(current_url().'?offset'.($offset + 1));
}
This would take one row, send it to api, update the page and use the next row. It will alos prevent the page from having a timeout. However it would most likely take a while with 30 000 records and refreshes, so you may wanna adjust your LIMIT ?, 1 to a higher number than 1 and go result() and foreach() multiple apis per pageload.
Well, there'se the row() method, which returns just one row as an object, or the row_array() method, which does the same but returns an array (of course).
So you could do something like
$sql = "SELECT * FROM yourtable";
$resultSet = $this->db->query($sql);
$total = $resultSet->num_rows();
for($i=0;$i<$total;$i++) {
$row = $resultSet->row_array($i);
}
This fetches in a loop each row from the whole result set.
Which is about the same as fetching everyting and looping over the $this->db->query($sql)->result() method calls I believe.
If you want a row at a time either you make 30.000 calls, or you select all the results and fetch them one at a time or you fetch all and walk over the array. I can't see any way out now.
In my controller I have called a model that makes a mysql query to fetch information from table. It is working okay but now under the same function I want to call another model and make a query based on one of the results from the previous mysql query. (The field name which I want to get the result of is "batch") . I have tried to get the value (batch) right in my controller, pass it into the model and then tried to make the second query but it seems like the second model is not getting the value from the controller and hence its not working. Would you please kindly help me with this?
Thanks in Advance :)
Here is my Controller
function Get($id){
$this->load->model('mod_studentprofile');
$data['query']= $this->mod_studentprofile->student_get($id);
// To get the batch name
$batch= $query ['batch']; // This I get from the above query result.
$this->load->model('batchname');
$data['query1']= $this->batchname->batchname($batch);
$data['tab'] = "Student Profile";
$data['main_content']='studentprofile';
$this->load->view('includes/template',$data);
}
Here is my model number 1
function student_get($id)
{
$query=$this->db->get_where('student',array('studentid'=>$id));
return $query->row_array();
}
Here is my model number 2
function batchname($batch)
{
$query1=$this->db->get_where('batch',array('batchid'=>$batch));
return $query1->row_array();
}
Well, you're not actually assigning anything to $batch, how about this:
$batch= $data['query'];
This now passes the variable along. As a side note, you can pass it as a paramater and be done with it in a single line, dependency injection style:
$data['query1']= $this->batchname->batchname($this->mod_studentprofile->student_get($id));
Are you getting a value back from the first query?
I would log the value you are getting back from the first query in your controller.
log_message('debug', 'Batch value is '.$batch);
And also put in some debug to see what the query that is being ran.
function batchname($batch)
{
$query1=$this->db->get_where('batch',array('batchid'=>$batch));
$str = $this->db->last_query();
log_message('debug', 'Batchname Query: '.$str);
return $query1->row_array();
}