I've got a similar list:
list = [',99', ',48', ',48', ',44', ',80', ',82', ',88', ',90', '1,1']
I just want the number to the right of the comma, but when I try splitting:
newList = list.split(',')
I get:
AttributeError: 'list' object has no attribute 'split'
here split will not work because javascript method .split() is to convert string into array and but here list is an object. you can try console.log(typeof variable); to check type of any variable.
So here you can simply use jquery function .each() most common function used for traversing an javascript object.
Try below solution:
var list = [',99', ',48', ',48', ',44', ',80', ',82', ',88', ',90', '1,1'];
var new_list = [];
$(list).each(function( index, item ) {
var item_array = item.split(',');
$(item_array).each(function( i, num ) {
if(num && num != '' && typeof num != 'undefined'){
new_list.push(num);
}
});
});
then use new_list instead of list as it will contain desired output:
["99", "48", "48", "44", "80", "82", "88", "90", "1", "1"]
OR can try alternate way:
var list = [',99', ',48', ',48', ',44', ',80', ',82', ',88', ',90', '1,1'];
var list_str = list.toString();
list = list_str.split(',');
list = list.filter(function(item){
if(!!item){
return item;
}
});
Related
I'm trying to create a Trie structure in Zig using Zigs StringHashMap.
I am able to get it to work a bit, but only by using a "inline" for loop which is not really usable as this requires the paths to be known at compile time :-(
Any help/explanation would be much appreciated :-)
The code:
const std = #import("std");
const Allocator = std.mem.Allocator;
const print = std.debug.print;
const expect = std.testing.expect;
const HashMap = struct {
value: u8,
children: std.StringHashMap(*HashMap),
};
fn newHashMap(allocator: Allocator, value: u8) HashMap {
return HashMap{
.value = value,
.children = std.StringHashMap(*HashMap).init(allocator),
};
}
fn showTree(root: *std.StringHashMap(*HashMap), keys:[3][]const u8 ) void {
var hashMap = root;
for (keys) |key| {
print("get key {s}\n", .{key});
var value = hashMap.get(key);
if (value) |node| {
print("we got a value for {s}:{}\n", .{key,node.value});
hashMap = &node.children;
} else {
print("no value for {s}\n", .{key});
break;
}
}
}
test "HashMap" {
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const gpaAllocator = gpa.allocator();
var arena = std.heap.ArenaAllocator.init(gpaAllocator);
defer {
arena.deinit();
const leaked = gpa.deinit();
if (leaked) expect(false) catch #panic("TEST FAIL"); //fail test; can't try in defer as defer is executed after we return
}
const allocator = arena.allocator();
var root = &std.StringHashMap(*HashMap).init(allocator);
var hashMap = root;
const keys = [_][]const u8{ "a", "b", "c" };
const values: [3]u8 = .{ 1, 2, 3 };
// create tree
inline for (keys) |key, i| {
print("put key {s}:{}\n", .{ key, values[i] });
var newNode = newHashMap(allocator, values[i]);
try hashMap.put(key, &newNode);
showTree(root,keys);
hashMap = &newNode.children;
}
showTree(root,keys);
}
This prints:
Test [1/1] test "HashMap"...
put key a:1
put key b:2
put key c:3
get key a
we got a value for a:1
get key b
we got a value for b:2
get key c
we got a value for c:3
All 1 tests passed.
as expected.
Removing the 'inline' results in:
Test [1/1] test "HashMap"...
put key a:1
put key b:2
put key c:3
get key a
we got a value for a:3
get key b
no value for b
All 1 tests passed.
The answer turned out to be quite obvious (with hindsight ;-)) as mentioned in 1:
var declarations inside functions are stored in the function's stack frame. Once a function returns, any Pointers to variables in the function's stack frame become invalid references, and dereferencing them becomes unchecked Undefined Behavior.
This explains the strange behaviour in a loop without inline.
The pointers just get overwritten resulting in Undefined Behaviour.
By adding 'inline' the loop is unwound and then there is no pointer reuse, hence the correct output.
The correct way of dealing with this is to allocate the struct explicitly and pass around the pointer to the struct as shown in 2.
Once that is sorted it all makes sense.
https://ziglang.org/documentation/master/#Where-are-the-bytes
https://www.reddit.com/r/Zig/comments/s6v8t3/idiomatic_zig_for_initializing_an_allocated/
For reference, the working code without 'inline' below:
const std = #import("std");
const Allocator = std.mem.Allocator;
const print = std.debug.print;
const expect = std.testing.expect;
const HashMap = struct {
value: u8,
children: std.StringHashMap(*HashMap),
};
fn newHashMap(allocator: Allocator, value: u8) !*HashMap {
const node = try allocator.create(HashMap);
node.* = .{
.value = value,
.children = std.StringHashMap(*HashMap).init(allocator),
};
return node;
}
fn showTree(root: *std.StringHashMap(*HashMap), keys:[3][]const u8 ) void {
var hashMap = root;
for (keys) |key| {
print("get key {s}\n", .{key});
var value = hashMap.get(key);
if (value) |node| {
print("we got a value for {s}:{}\n", .{key,node.value});
hashMap = &node.children;
} else {
print("no value for {s}\n", .{key});
break;
}
}
}
test "HashMap" {
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const gpaAllocator = gpa.allocator();
var arena = std.heap.ArenaAllocator.init(gpaAllocator);
defer {
arena.deinit();
const leaked = gpa.deinit();
if (leaked) expect(false) catch #panic("TEST FAIL"); //fail test; can't try in defer as defer is executed after we return
}
const allocator = arena.allocator();
var root = &std.StringHashMap(*HashMap).init(allocator);
var hashMap = root;
const keys = [_][]const u8{ "a", "b", "c" };
const values: [3]u8 = .{ 1, 2, 3 };
// create tree
for (keys) |key, i| {
print("put key {s}:{}\n", .{ key, values[i] });
var newNode = try newHashMap(allocator, values[i]);
try hashMap.put(key, newNode);
hashMap = &newNode.children;
}
showTree(root,keys);
}
I am using fold on an array which hasn't been assign to a variable and want to check whether the element is the last value. With a conventional for loop I can do this:
List<int> ints = [1, 2, 3];
int sum = 0;
for (int num in ints]) {
if (num != ints.last) {
sum = sum + num;
}
}
print(sum);
Is it possible to do this with fold instead?
int foldSum = [1, 2, 3].fold(0, (int prev, element) => prev + element);
print(foldSum);
I can't find any way of check when fold is at the last value. Note: this is a simplified example of my problem and the reason the list isn't assigned to a variable (allowing me to use .last) is because it is the result of a call to .map().
For completeness, below is the actual code (which won't obviously won't be runnable in isolation but will help illustrate my problem) I am trying to convert to use .map and .fold:
String get fieldsToSqlInsert {
String val = "";
for (Column column in columns) {
if (data.containsKey(column.name)) {
val = '$val "${data[column.name]}"';
} else {
val = "$val NULL";
}
if (column != columns.last) {
val = "$val,";
}
}
return val;
}
But it doesn't work because I don't know how to check when fold is at the final element:
String get fieldsToSqlInsert => columns
.map((column) =>
data.containsKey(column.name) ? data[column.name] : "NULL")
.fold("", (val, column) => column != columns.last ? "$val," : val);
If you simply want to exclude the last element from further calculation, you can just use take to do so:
String get fieldsToSqlInsert => columns.take(columns.length - 1)...
I have this code
String encrypt(String x) {
String out;
var _x = x.codeUnits;
List dict;
/* <dict_assignment> */
dict[0] = 'a';
dict[1] = 'b';
dict[2] = 'c';
dict[3] = 'd';
dict[4] = 'e';
dict[5] = 'f';
dict[6] = 'g';
dict[7] = 'h';
dict[8] = 'i';
dict[9] = 'j';
/* </dict_assignment> */
_x.toList().forEach((i) {
var _i = i.toString();
_i.split("").forEach((k) {
var _k = int.parse(k);
print(_k);
print(dict[_k]);
out += dict[_k];
});
});
return out;
}
(Yes I'm writing HTML tags as comments in Dart...sue me)
(Idk why my indentations are messed up)
For some reason when I use this same function with a random string like this
var x = encrypt("hmm interesting");
I keep getting this
Unhandled exception:
NoSuchMethodError: The method '[]=' was called on null.
Receiver: null
Tried calling: []=(0, "a")
#0 Object.noSuchMethod (dart:core-patch/object_patch.dart:54:5)
Please help me I'm actually confused why this is happening
You have not initialized your dict variable, so it contains null.
If you change List dict; to List dict = []; then that would start working.
You also haven't initialized out.
The remainder of the code is leaning towards being overly complicated, and can be optimized as well. Here is a suggestion:
String encrypt(String x) {
var out = StringBuffer();
const dict = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j'];
for (var i in x.codeUnits) { // x.codeUnits is a list. Use for-in to iterate it.
for (var k in i.toString().codeUnits) {
var _k = k ^ 0x30; // Best way to convert code unit for 0-9 into integer 0-9.
// print(_k);
// print(dict[_k]);
out.write(dict[_k]); // Use a StringBuffer instead of repeated concatenation.
}
}
return out.toString();
}
It does not appear to be a decryptable encryption. The string "77" and the string "ᖳ" (aka "\u15b3") both encrypt to "ffff".
Or, if you want to "code-golf" rather than be readable or close to the original, it can also be a one-liner:
String encrypt(String x) => [
for (var i in x.codeUnits)
for (var k in "$i".codeUnits) "abcdefghij"[k ^ 0x30]
].join("");
I am new to Gatling and scala. facing issue on passing jsonpath saved variable from one repeat section to another forEach repeat section.
following variable "dcIds" is not able to pass to forEach section. Also please direct me to make the below code more better.
var dcIdd = ""
val r = new scala.util.Random
def orderRef() = r.nextInt(100)
def getCreateRequest: String = {
val data = s"""
[{
"name":"DC_${orderRef()}",
"location":"Seattle, Washington, USA",
"type":"Colocation"
}]
""".stripMargin
data
}
def createAppRequest: String = {
val data = s"""
[{
"name":"App_${orderRef()}",
"owner":"a#a.com",
"dataCenterId":"${dcIdd}",
"strategy":"Rehost",
"migrationStrategy":"Rehost"}]
}]
""".stripMargin
data
}
val scn = scenario("Add DC")
.repeat(DcIterations, "index") {
exec(
http("List_plans")
.get(uri2 + "?plan_id=")
.headers(headers_sec)
.resources(
http("DC add")
.post(uri2)
.headers(headers_sec)
.body(StringBody(session => getCreateRequest))
.check(jsonPath("$.ids[*]").findAll.saveAs("dcIds"))))
}
.foreach("${dcIds}", "dcId") {
dcIdd = "${dcId}"
repeat(AppIterations, "index") {
exec(http("Add Application")
.post(uri1 + "/applications/${dcId}")
.headers(headers_sec)
.body(StringBody(session => createAppRequest))
)
}
}
Is it possible to filter numbers from the variable.
I can show you one example here from the link http://jsfiddle.net/sweetmaanu/82r5v/6/
I need to get only numbers from the alert message
Simply replace the box string out of it.
DEMO
for (var i = 0; i < order.length; i++) {
order[i] = order[i].replace('box', '');
}
So instead of box1, box2, box3, box4 you want to see 1,2,3,4
You can use a regular expression like this:
var order = $("#boxes").sortable("toArray") + "";
alert(order.replace(/[^0-9,]/g, ''));
I also had to append an empty string to order because it wasn't being recognized as a string object even though the jQuery documentation says it should be when you call sortable("toArray").
change var order = $("#boxes").sortable("toArray");
to var order = $("#boxes").sortable("toArray").join(',').replace(/[a-zA-Z]/gi, "");
Demo: http://jsfiddle.net/82r5v/13/
// Remove all non-digits from the string
'box1'.replace(/\D/g, ''); // => '1'
// Same, but try to make the string a number
Number('box1'.replace(/\D/g, '')); // => 1
// Shorthand for making an object a number (+o is the same as Number(o))
+'box1'.replace(/\D/g, ''); // => 1
// parseInt(s) works if the number is at the beginning
parseInt('1box'); // => 1
// but not if it occurs later
parseInt('box1'); // => NaN
Maybe using regular expressions something like this:
`alert(order.join(',').match(/\d/g));`
To return the array as numbers.
(\d matches all digits, g signifies a global match wildcard)
One way to do it by using regular expressions - http://jsfiddle.net/holodoc/82r5v/14/
$(document).ready(function() {
var arrValuesForOrder = ["2", "1", "3", "4"];
var ul = $("#boxes"),
items = $("#boxes li.con");
for (var i = arrValuesForOrder[arrValuesForOrder.length - 1]; i >= 0; i--) {
// arrValuesForOrder[i] element to move
// i = index to move element at
ul.prepend(items.get(arrValuesForOrder[i] - 1));
}
$("#boxes").sortable({
handle : '.drag',
update: function() {
var order = $("#boxes").sortable("toArray");
var sorted = [];
$.each(order, function(index, value){
sorted.push(value.match(/box(\d+)/)[1]);
})
alert(sorted);
}
});
});