yourList1 = yourList1.Distinct()
.Where(x => !(yourList2.Any(x)) && !(yourList3.Any(x)))
.ToList();yourList = yourList.Distinct().ToList();I think Somnid is doing great, but just in case it helps, taken from the "folding" wikipedia page
I think Somnid is doing great, but just in case it helps, taken from the "folding" wikipedia page
https://en.wikipedia.org/wiki/Fold_(higher-order_function)
Reduce is doing the transformation above...
A table [ 1; 2; 3; 4; 5 ] is thus converted into f( f( f( f( f( z, 1 ), 2 ), 3 ), 4 ), 5 )
So :
with multiplication and z=1, you get ((1*1)*2)*3)*4)*5
with addition and z=0, you get ((0+1)+2)+3)+4)+5
Folding is a great (and efficient) feature of functional languages (and available in a large number of languages, in fact)
The initialization is the second parameter of reduce, the one that act as the first parameter of the function you provide for the first call (the second time, it's the result of the first call that will be used).
__global__ void kernel_csr(int m,int n,double *d_a,int *count_block)
{
extern __shared__ int count_thread[];
unsigned int tid = threadIdx.x;
unsigned int i = blockIdx.x*blockDim.x+threadIdx.x;
unsigned int count = 0;
// thread counts all nonzero elements in its row
countdata[tid] = 0; //initialize
for(int col = 0;col<n;col++){
if(d_a[i*n+col] >= 1e-17) count++;
}
count_thread[tid] = count;
__syncthreads(); // syncs all threads in a block
//do reduction in shared memory
for(unsigned int s = blockDim.x/2; s>0; s>>=1){
if(tid < s){
count_thread[tid] += count_thread[tid+s];
}
__syncthreads();
}
//write result for this block to global memory
if(tid==0) count_block[blockIdx.x]=count_thread[0]; //holds nonzeros inside a block
}Yeah, bitshift.
It probably should only be chosen on readability, I'm sure all those instructions will result in a bitshift in assembly with any decent compiler.
same thing
std::vector<MyClass *> myVector;
// I add three elements to it:
myVector.push_back (new MyClass(att1, att2));
myVector.push_back (new MyClass(att1, att2));
myVector.push_back (new MyClass(att1, att2));// Erase first element:
std::vector<MyClass *>::iterator iterator;
iterator = MyVector.begin();
delete *iterator;
myVector.erase (myVector.begin()+0);int containsDynArr(DynArr *v, int val)
{
int x;
for (x=0; x < v->size; x++)
{
if (v->data[x] == val)
{
return 1;
}
}
return 0; for (int i = 0; i < numElements; i++)
{
containsDynArr(a, i);
}
complexity because you know, worst case we loop over every element once and find nothing. That's N elements. ?function pal(str) {
str.toLowerCase();
return str;
}
pal("Eye");function pal(str) {
str.toLowerCase().replace(str, 'wat');
}
pal("Eye");The string "eye" doesn't contain "Eye", though. Case matters.
for (int i = 0; i < numElements; i++)
{
for (x=0; x < v->size; x++)
{
if (v->data[x] == i)
{
// ...
}
}
}player_id int auto_increment
image blob
name varchar
position varcharpublic class Players extends BaseActivity {
//Creating a List of players
private List<PlayersGetSet> listPlayers;
private RecyclerView recyclerView;
private RecyclerView.LayoutManager layoutManager;
private RecyclerView.Adapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// substantiate nav drawer
setContentView(R.layout.activity_players);
setNavDrawer(new MainNavDrawer(this));
//Initializing Views
recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
//Initializing our players list
listPlayers = new ArrayList<>();
//Calling method to get data
getData();
}
private void getData() {
//Showing a progress dialog
final ProgressDialog loading = ProgressDialog.show(this,"Loading Data", "Please wait...",false,false);
//Creating a json array request
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(Config.DATA_URL,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
//Dismissing progress dialog
loading.dismiss();
//calling method to parse json array
parseData(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
loading.dismiss();
}
});
//Creating request queue
RequestQueue requestQueue = Volley.newRequestQueue(this);
//Adding request to the queue
requestQueue.add(jsonArrayRequest);
}
//This method will parse json data
private void parseData(JSONArray array){
for(int i = 0; i<array.length(); i++) {
PlayersGetSet players = new PlayersGetSet();
JSONObject json = null;
try {
json = array.getJSONObject(i);
players.setImageUrl(json.getString(Config.KEY_IMAGE));
players.setName(json.getString(Config.KEY_NAME));
players.setPosition(json.getString(Config.KEY_POSITION));
} catch (JSONException e) {
e.printStackTrace();
}
listPlayers.add(players);
}
//Finally initializing our adapter
adapter = new CardAdapter(listPlayers, this);
//Adding adapter to recyclerview
recyclerView.setAdapter(adapter);
}
}public class PlayersGetSet {
private String image;
private String name;
private String position;
//Getters and Setters
public String getImageUrl() {
return image;
}
public void setImageUrl(String image) {
this.image = image;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPosition() {
return position;
}
public void setPosition(String position) {
this.position = position;
}public class CustomVolleyRequest {
private static CustomVolleyRequest customVolleyRequest;
private static Context context;
private RequestQueue requestQueue;
private ImageLoader imageLoader;
private CustomVolleyRequest(Context context) {
this.context = context;
this.requestQueue = getRequestQueue();
imageLoader = new ImageLoader(requestQueue,
new ImageLoader.ImageCache() {
private final LruCache<String, Bitmap>
cache = new LruCache<String, Bitmap>(20);
@Override
public Bitmap getBitmap(String url) {
return cache.get(url);
}
@Override
public void putBitmap(String url, Bitmap bitmap) {
cache.put(url, bitmap);
}
});
}
public static synchronized CustomVolleyRequest getInstance(Context context) {
if (customVolleyRequest == null) {
customVolleyRequest = new CustomVolleyRequest(context);
}
return customVolleyRequest;
}
public RequestQueue getRequestQueue() {
if (requestQueue == null) {
Cache cache = new DiskBasedCache(context.getCacheDir(), 10 * 1024 * 1024);
Network network = new BasicNetwork(new HurlStack());
requestQueue = new RequestQueue(cache, network);
requestQueue.start();
}
return requestQueue;
}
public ImageLoader getImageLoader() {
return imageLoader;
}
}public class CardAdapter extends RecyclerView.Adapter<CardAdapter.ViewHolder> {
private ImageLoader imageLoader;
private Context context;
//List of players
List<PlayersGetSet> players;
public CardAdapter(List<PlayersGetSet> players, Context context){
super();
//Getting all the players
this.players = players;
this.context = context;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.players_list, parent, false);
ViewHolder viewHolder = new ViewHolder(v);
return viewHolder;
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
PlayersGetSet player = players.get(position);
imageLoader = CustomVolleyRequest.getInstance(context).getImageLoader();
imageLoader.get(player.getImageUrl(), ImageLoader.getImageListener(holder.imageView, R.mipmap.ic_launcher, android.R.drawable.ic_dialog_alert));
holder.imageView.setImageUrl(player.getImageUrl(), imageLoader);
holder.textViewName.setText(player.getName());
holder.textViewRank.setText(String.valueOf(player.getPosition()));
}
@Override
public int getItemCount() {
return players.size();
}
class ViewHolder extends RecyclerView.ViewHolder{
public NetworkImageView imageView;
public TextView textViewName;
public TextView textViewRank;
public ViewHolder(View itemView) {
super(itemView);
imageView = (NetworkImageView) itemView.findViewById(R.id.imageViewPlayer);
textViewName = (TextView) itemView.findViewById(R.id.textViewName);
textViewRank= (TextView) itemView.findViewById(R.id.textViewPosition);
}
}
}<?php
if($_SERVER['REQUEST_METHOD']=='GET'){
$id = $_GET['player_id'];
require_once('dbConnect.php');
$sql = "select * from players where player_id = '$id'";
$r = mysqli_query($con,$sql);
$res = mysqli_fetch_array($r);
$result = array();
array_push($result,array(
"image"=>$res['image'],
"name"=>$res['name'],
"position"=>$res['position']
)
);
echo json_encode(array("result"=>$result));
mysqli_close($con);
}04-21 11:52:41.940 32309-32309/? E/Zygote: v2
04-21 11:52:41.940 32309-32309/? E/Zygote: accessInfo : 0
04-21 11:52:43.650 32309-32535/com.android.matty.blairgowrie2006 E/GMPM: getGoogleAppId failed with status: 10
04-21 11:52:43.650 32309-32535/com.android.matty.blairgowrie2006 E/GMPM: Uploading is not possible. App measurement disabled
04-21 11:53:03.300 32309-32309/com.android.matty.blairgowrie2006 E/RecyclerView: No adapter attached; skipping layout
04-21 11:53:03.350 32309-32309/com.android.matty.blairgowrie2006 E/RecyclerView: No adapter attached; skipping layout
04-21 11:53:03.380 32309-32309/com.android.matty.blairgowrie2006 E/RecyclerView: No adapter attached; skipping layout
04-21 11:53:04.580 32309-32309/com.android.matty.blairgowrie2006 E/ViewRootImpl: sendUserActionEvent() mView == null com.android.volley.ParseError: org.json.JSONException: Value <!DOCTYPE of type java.lang.String cannot be converted to JSONArraycom.android.volley.ParseError: org.json.JSONException:
Value{"result":[{"image": *MASSIVELY LONG STRING OF CHARACTERS HERE*","name":"Tam","position":"GK"}]}
of type org.json.JSONObject cannot be converted to JSONArrayJSONArray array = responseObject.getJSONArray("result");type 'a Transaction =
| NoConnection
| InvalidKey of string
| Timeout
| NoItemForKey
| Ok of 'a
// Pretend there is a function that takes
// a DB of 'a and a key and returns a Transaction
let findKeyInDB default key db =
match DB.find key db with
| NoConnection -> failwith "No connection"
| Ok a -> a
| _ -> default
let getStringOrDefault (db: string DB) =
let findKey = findKeyInDB "" in
let s1 = findKey "1" db in
let s2 = findKey "2" db in
String.concat s1 s2private void getData() {
//Showing a progress dialog
final ProgressDialog loading = ProgressDialog.show(this, "Loading Players", "Please wait...", false, false);
//Creating a json array request
//TODO - CREATE JSONObjectRequest or StringRequest instead
// Request a string response from the provided URL.
StringRequest stringRequest = new StringRequest(Request.Method.GET, Config.DATA_URL,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
//Dismissing progress dialog
loading.dismiss();
//calling method to parse json array
parseData(response);
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
// we are getting a parse error
Toast bread = Toast.makeText(getApplicationContext(), error.toString(), Toast.LENGTH_LONG);
bread.show();
}
});
/*JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(Config.DATA_URL,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
//Dismissing progress dialog
loading.dismiss();
// JSONArray array = response.getJSONArray("result");
//calling method to parse json array
parseData(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
// we are getting a parse error
Toast bread = Toast.makeText(getApplicationContext(), error.toString(), Toast.LENGTH_LONG);
bread.show();
}
}); */
//Creating request queue
RequestQueue requestQueue = Volley.newRequestQueue(this);
//Adding request to the queue
requestQueue.add(stringRequest);
} //This method will parse json data
private void parseData(JSONArray array){
for(int i = 0; i<array.length(); i++) {
PlayersGetSet players = new PlayersGetSet();
JSONObject json = null;
try {
json = array.getJSONObject(i);
players.setImageUrl(json.getString(Config.KEY_IMAGE));
players.setName(json.getString(Config.KEY_NAME));
players.setPosition(json.getString(Config.KEY_POSITION));
} catch (JSONException e) {
e.printStackTrace();
}
listPlayers.add(players);
}
//Finally initializing our adapter
adapter = new CardAdapter(listPlayers, this);
//Adding adapter to recyclerview
recyclerView.setAdapter(adapter);
}Functional languages grammar are just awful when you want to indent them properly.
I have had way more problems indenting imperative c code because of the constant tension between tersity and readability. In ml I typically get both.
Begin end is just redundant syntax for ( ) in OCaml. Don't use it!
I typically use four spaces but I understand 2 spaces is common. I have never had right-creep be problematic in ML, but I have had it happen in Haskell (very often). The lack of significant indentation is very helpful in this regard. There are also a lot of conventions that reduce indentation, such as
if condition then expr else
more code;
more code;
...That's probably the simplest rule there is. Always at the end of a let line, unless you want to distinguish the result value after a long series of let bindings.
JsonObjectRequest jsonObjRequest = new JsonObjectRequest(Request.Method.GET, Config.DATA_URL, null,
new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response){
//Dismissing progress dialog
loading.dismiss();
//print out response and confirm that you are receiving a valid response
JSONArray array = response.getJSONArray("result");
//print out array here to confirm that it now has contents of "result"
//calling method to parse json array
parseData(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
// we are getting a parse error
Toast bread = Toast.makeText(getApplicationContext(), error.toString(), Toast.LENGTH_LONG);
bread.show();
}
});To each its own, I guess...
OCaml guidelines ask for begin...end instead of ()
and I agree, I think that in many cases, it's just unreadable with ()
Well, when it's possible, I'll do this, but there's several cases where it's just impossible (or would result in a lot of "when ..." constructs, which seems worse to me)
When they depend on each others, that's not a solution...
For normal definitions, that's my take, but when I'm having local functions, things get really messier.
can't do that if it's a singly linked list ¯\_(ツ
Okay, true. That's unfortunate. What are you asking for, though? Braces?
I believe you. But my experience is still that my code is a lot shorter, less indented, and easier to read in languages like OCaml or F#.
Huh? Why not let rec . . . and ?
I still leave it at the end of the line.
Can you use Jakson in Android? I would just create some models that replicate the JSON structure and use it to map it automatically.
Depending on what you're writing, a lot shorter, I'll give you that.
Because you can't use a function call in the right hand of a let rec to statically prevent recursive definitions that could trigger a bus error.
let rec a = 2 and f = function 0 -> 1 | x -> a* (f (x-1)) in f 5;;Well, that's not THAT bad... And I probably wouldn't think so much about it if I was only writing code for myself (or experienced programmers).But look, I can't discount your personal experience. I'm sorry you've had such headaches with it.
let Index elem v =
let rec Aux = fun
| a b when a>b -> failwith "Not found"
| a b -> let c = (a+b)/2 in
if v.(c) = elem then c else
if v.(c) > elem then (Aux a (c-1)) else
(Aux (c+1) b)
in Aux 0 (vect_length v - 1);;let Index elem v =
let rec Aux a b = let c=(a+b)/2 in match a, b, c with
| a, b, _ when a > b -> failwith "Not found"
| _, _, c when v.(c) = elem -> c
| a, _, c when v.(c) > elem -> Aux a (c-1)
| _, b, c -> Aux (c+1) b
in Aux 0 (vect_length v - 1);;