Summary
Type BST (*) Heap
Insert average log(n) 1
Insert worst log(n) log(n) or n (***)
Find any worst log(n) n
Find max worst 1 (**) 1
Create worst n log(n) n
Delete worst log(n) log(n)
All average times on this table are the same as their worst times except for Insert.
*
: everywhere in this answer, BST == Balanced BST, since unbalanced sucks asymptotically**
: using a trivial modification explained in this answer***
: log(n)
for pointer tree heap, n
for dynamic array heapAdvantages of binary heap over a BST
average time insertion into a binary heap is O(1)
, for BST is O(log(n))
. This is the killer feature of heaps.
There are also other heaps which reach O(1)
amortized (stronger) like the Fibonacci Heap, and even worst case, like the Brodal queue, although they may not be practical because of non-asymptotic performance: Are Fibonacci heaps or Brodal queues used in practice anywhere?
binary heaps can be efficiently implemented on top of either dynamic arrays or pointer-based trees, BST only pointer-based trees. So for the heap we can choose the more space efficient array implementation, if we can afford occasional resize latencies.
binary heap creation is O(n)
worst case, O(n log(n))
for BST.
Advantage of BST over binary heap
search for arbitrary elements is O(log(n))
. This is the killer feature of BSTs.
For heap, it is O(n)
in general, except for the largest element which is O(1)
.
"False" advantage of heap over BST
heap is O(1)
to find max, BST O(log(n))
.
This is a common misconception, because it is trivial to modify a BST to keep track of the largest element, and update it whenever that element could be changed: on insertion of a larger one swap, on removal find the second largest. Can we use binary search tree to simulate heap operation? (mentioned by Yeo).
Actually, this is a limitation of heaps compared to BSTs: the only efficient search is that for the largest element.
Average binary heap insert is O(1)
Sources:
Intuitive argument:
In a binary heap, increasing the value at a given index is also O(1)
for the same reason. But if you want to do that, it is likely that you will want to keep an extra index up-to-date on heap operations How to implement O(logn) decrease-key operation for min-heap based Priority Queue? e.g. for Dijkstra. Possible at no extra time cost.
GCC C++ standard library insert benchmark on real hardware
I benchmarked the C++ std::set
(Red-black tree BST) and std::priority_queue
(dynamic array heap) insert to see if I was right about the insert times, and this is what I got:
So clearly:
heap insert time is basically constant.
We can clearly see dynamic array resize points. Since we are averaging every 10k inserts to be able to see anything at all above system noise, those peaks are in fact about 10k times larger than shown!
The zoomed graph excludes essentially only the array resize points, and shows that almost all inserts fall under 25 nanoseconds.
BST is logarithmic. All inserts are much slower than the average heap insert.
BST vs hashmap detailed analysis at: What data structure is inside std::map in C++?
GCC C++ standard library insert benchmark on gem5
gem5 is a full system simulator, and therefore provides an infinitely accurate clock with with m5 dumpstats
. So I tried to use it to estimate timings for individual inserts.
Interpretation:
heap is still constant, but now we see in more detail that there are a few lines, and each higher line is more sparse.
This must correspond to memory access latencies are done for higher and higher inserts.
TODO I can't really interpret the BST fully one as it does not look so logarithmic and somewhat more constant.
With this greater detail however we can see can also see a few distinct lines, but I'm not sure what they represent: I would expect the bottom line to be thinner, since we insert top bottom?
Benchmarked with this Buildroot setup on an aarch64 HPI CPU.
BST cannot be efficiently implemented on an array
Heap operations only need to bubble up or down a single tree branch, so O(log(n))
worst case swaps, O(1)
average.
Keeping a BST balanced requires tree rotations, which can change the top element for another one, and would require moving the entire array around (O(n)
).
Heaps can be efficiently implemented on an array
Parent and children indexes can be computed from the current index as shown here.
There are no balancing operations like BST.
Delete min is the most worrying operation as it has to be top down. But it can always be done by "percolating down" a single branch of the heap as explained here. This leads to an O(log(n)) worst case, since the heap is always well balanced.
If you are inserting a single node for every one you remove, then you lose the advantage of the asymptotic O(1) average insert that heaps provide as the delete would dominate, and you might as well use a BST. Dijkstra however updates nodes several times for each removal, so we are fine.
Dynamic array heaps vs pointer tree heaps
Heaps can be efficiently implemented on top of pointer heaps: Is it possible to make efficient pointer-based binary heap implementations?
The dynamic array implementation is more space efficient. Suppose that each heap element contains just a pointer to a struct
:
the tree implementation must store three pointers for each element: parent, left child and right child. So the memory usage is always 4n
(3 tree pointers + 1 struct
pointer).
Tree BSTs would also need further balancing information, e.g. black-red-ness.
the dynamic array implementation can be of size 2n
just after a doubling. So on average it is going to be 1.5n
.
On the other hand, the tree heap has better worst case insert, because copying the backing dynamic array to double its size takes O(n)
worst case, while the tree heap just does new small allocations for each node.
Still, the backing array doubling is O(1)
amortized, so it comes down to a maximum latency consideration. Mentioned here.
Philosophy
BSTs maintain a global property between a parent and all descendants (left smaller, right bigger).
The top node of a BST is the middle element, which requires global knowledge to maintain (knowing how many smaller and larger elements are there).
This global property is more expensive to maintain (log n insert), but gives more powerful searches (log n search).
Heaps maintain a local property between parent and direct children (parent > children).
The top node of a heap is the big element, which only requires local knowledge to maintain (knowing your parent).
Comparing BST vs Heap vs Hashmap:
BST: can either be either a reasonable:
heap: is just a sorting machine. Cannot be an efficient unordered set, because you can only check for the smallest/largest element fast.
hash map: can only be an unordered set, not an efficient sorting machine, because the hashing mixes up any ordering.
Doubly-linked list
A doubly linked list can be seen as subset of the heap where first item has greatest priority, so let's compare them here as well:
O(1)
worst case since we have pointers to the items, and the update is really simpleO(1)
average, thus worse than linked list. Tradeoff for having more general insertion position.O(n)
for bothAn use case for this is when the key of the heap is the current timestamp: in that case, new entries will always go to the beginning of the list. So we can even forget the exact timestamp altogether, and just keep the position in the list as the priority.
This can be used to implement an LRU cache. Just like for heap applications like Dijkstra, you will want to keep an additional hashmap from the key to the corresponding node of the list, to find which node to update quickly.
Comparison of different Balanced BST
Although the asymptotic insert and find times for all data structures that are commonly classified as "Balanced BSTs" that I've seen so far is the same, different BBSTs do have different trade-offs. I haven't fully studied this yet, but it would be good to summarize these trade-offs here:
See also
Similar question on CS: https://cs.stackexchange.com/questions/27860/whats-the-difference-between-a-binary-search-tree-and-a-binary-heap
I see that a few important reasons for doing as few new's as possible are missed:
new
has a non-deterministic execution timeCalling new
may or may not cause the OS to allocate a new physical page to your process this can be quite slow if you do it often. Or it may already have a suitable memory location ready, we don't know. If your program needs to have consistent and predictable execution time (like in a real-time system or game/physics simulation) you need to avoid new
in your time critical loops.
new
is an implicit thread synchronizationYes you heard me, your OS needs to make sure your page tables are consistent and as such calling new
will cause your thread to acquire an implicit mutex lock. If you are consistently calling new
from many threads you are actually serialising your threads (I've done this with 32 CPUs, each hitting on new
to get a few hundred bytes each, ouch! that was a royal p.i.t.a. to debug)
The rest such as slow, fragmentation, error prone, etc have already been mentioned by other answers.
What are the problems of static and stack?
The problem with "static" allocation is that the allocation is made at compile-time: you can't use it to allocate some variable number of data, the number of which isn't known until run-time.
The problem with allocating on the "stack" is that the allocation is destroyed as soon as the subroutine which does the allocation returns.
I could write an entire application without allocate variables in the heap?
Perhaps but not a non-trivial, normal, big application (but so-called "embedded" programs might be written without the heap, using a subset of C++).
What garbage collector does ?
It keeps watching your data ("mark and sweep") to detect when your application is no longer referencing it. This is convenient for the application, because the application doesn't need to deallocate the data ... but the garbage collector might be computationally expensive.
Garbage collectors aren't a usual feature of C++ programming.
What could you do manipulating the memory by yourself that you couldn't do using this garbage collector?
Learn the C++ mechanisms for deterministic memory deallocation:
There are already some great answers but I would like to add a little visual explanation
Now, take a look at the image, there are
n/2^1
green nodes with height 0 (here 23/2 = 12)
n/2^2
red nodes with height 1 (here 23/4 = 6)
n/2^3
blue node with height 2 (here 23/8 = 3)
n/2^4
purple nodes with height 3 (here 23/16 = 2)
so there are n/2^(h+1)
nodes for height h
To find the time complexity lets count the amount of work done or max no of iterations performed by each node
now it can be noticed that each node can perform(atmost) iterations == height of the node
Green = n/2^1 * 0 (no iterations since no children)
red = n/2^2 * 1 (heapify will perform atmost one swap for each red node)
blue = n/2^3 * 2 (heapify will perform atmost two swaps for each blue node)
purple = n/2^4 * 3 (heapify will perform atmost three swaps for each purple node)
so for any nodes with height h maximum work done is n/2^(h+1) * h
Now total work done is
->(n/2^1 * 0) + (n/2^2 * 1)+ (n/2^3 * 2) + (n/2^4 * 3) +...+ (n/2^(h+1) * h)
-> n * ( 0 + 1/4 + 2/8 + 3/16 +...+ h/2^(h+1) )
now for any value of h, the sequence
-> ( 0 + 1/4 + 2/8 + 3/16 +...+ h/2^(h+1) )
will never exceed 1
Thus the time complexity will never exceed O(n) for building heap
Heap dumps anytime you wish to see what is being held in memory Out-of-memory errors Heap dumps - picture of in memory objects - used for memory analysis Java cores - also known as thread dumps or java dumps, used for viewing the thread activity inside the JVM at a given time. IBM javacores should a lot of additional information besides just the threads and stacks -- used to determine hangs, deadlocks, and reasons for performance degredation System cores
This command shows the configured heap sizes in bytes.
java -XX:+PrintFlagsFinal -version | grep HeapSize
It works on Amazon AMI on EC2 as well.
In Eclipse Folder there is eclipse.ini file. Increase size -Xms512m
-Xmx1024m
Never do premature assumption as other application code and usage can impact your function. So looking at function is isolation is of no use.
If you are serious with application then VTune it or use any similar profiling tool and look at hotspots.
Ketan
You also use this below to expand the memory
export _JAVA_OPTIONS="-Xms512m -Xmx1024m -Xss512m -XX:MaxPermSize=1024m"
Xmx
specifies the maximum memory allocation pool for a Java virtual machine (JVM)
Xms
specifies the initial memory allocation pool.
Xss
setting memory size of thread stack
XX:MaxPermSize
: the maximum permanent generation size
If you want to do a custom analysis of your heapdump then there's:
This library is fast but you will need to write your analysis code in Java.
From the docs:
what platform are you running?..
if its unix, maybe adding
alias java='java -Xmx1g'
to .bashrc (or similar) work
edit: Changing XmX to Xmx
For the record, we had the same problem today. We fixed it by using this option:
-XX:-UseConcMarkSweepGC
Apparently, this modified the strategy used for garbage collection, which made the issue disappear.
You can't do it using environment variables. It's done via "non standard" options. Run: java -X
for details. The options you're looking for are -Xmx
and -Xms
(this is "initial" heap size, so probably what you're looking for.)
You may find useful this implementation: http://www.codeproject.com/Articles/126751/Priority-queue-in-Csharp-with-help-of-heap-data-st.aspx
it is generic and based on heap data structure
I know there are a lot of answers here already, but none of them helped me. In the end I opened the file /etc/elasticsearch/jvm.options
and changed:
-Xms2G
-Xmx2G
to
-Xms256M
-Xmx256M
That solved it for me. Hopefully this helps someone else here.
public class CheckHeapSize {
public static void main(String[] args) {
// TODO Auto-generated method stub
long heapSize = Runtime.getRuntime().totalMemory();
// Get maximum size of heap in bytes. The heap cannot grow beyond this size.// Any attempt will result in an OutOfMemoryException.
long heapMaxSize = Runtime.getRuntime().maxMemory();
// Get amount of free memory within the heap in bytes. This size will increase // after garbage collection and decrease as new objects are created.
long heapFreeSize = Runtime.getRuntime().freeMemory();
System.out.println("heapsize"+formatSize(heapSize));
System.out.println("heapmaxsize"+formatSize(heapMaxSize));
System.out.println("heapFreesize"+formatSize(heapFreeSize));
}
public static String formatSize(long v) {
if (v < 1024) return v + " B";
int z = (63 - Long.numberOfLeadingZeros(v)) / 10;
return String.format("%.1f %sB", (double)v / (1L << (z*10)), " KMGTPE".charAt(z));
}
}
Here is my simple but efficient algorithm (in C++) for calculating running median from a stream of integers:
#include<algorithm>
#include<fstream>
#include<vector>
#include<list>
using namespace std;
void runningMedian(std::ifstream& ifs, std::ofstream& ofs, const unsigned bufSize) {
if (bufSize < 1)
throw exception("Wrong buffer size.");
bool evenSize = bufSize % 2 == 0 ? true : false;
list<int> q;
vector<int> nums;
int n;
unsigned count = 0;
while (ifs.good()) {
ifs >> n;
q.push_back(n);
auto ub = std::upper_bound(nums.begin(), nums.end(), n);
nums.insert(ub, n);
count++;
if (nums.size() >= bufSize) {
auto it = std::find(nums.begin(), nums.end(), q.front());
nums.erase(it);
q.pop_front();
if (evenSize)
ofs << count << ": " << (static_cast<double>(nums[nums.size() / 2 - 1] +
static_cast<double>(nums[nums.size() / 2]))) / 2.0 << '\n';
else
ofs << count << ": " << static_cast<double>(nums[nums.size() / 2]);
}
}
}
The bufferSize
specifies the size of the numbers sequence, on which the running median must be calculated. When reading numbers from the input stream ifs
the vector of the size bufferSize
is maintained in sorted order. The median is calculated by taking the middle of the sorted vector, if bufferSize
is odd, or the sum of the two middle elements divided by 2, when bufferSize
is even. Additinally, I maintain a list of last bufferSize
elements read from input. When a new element is added, I put it in the right place in sorted vector and remove from the vector the element added bufferSize
steps before (the value of the element retained in the front of the list). In the same time I remove the old element from the list: every new element is placed on the back of the list, every old element is removed from the front. After reaching the bufferSize
, both the list and the vector stop to grow, and every insertion of a new element is compensated be deletion of an old element, placed in the list bufferSize
steps before. Note, I do not care, whether I remove from the vector exactly the element, placed bufferSize
steps before, or just an element that has the same value. For the value of median it does not matter.
All calculated median values are output in the output stream.
You can use this configuration:
-startup
plugins/org.eclipse.equinox.launcher_1.3.0.v20120522-1813.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.gtk.linux.x86_64_1.1.200.v20120913-144807
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
-vmargs
-Xms512m
-Xmx1024m
-XX:+UseParallelGC
-XX:PermSize=256M
-XX:MaxPermSize=512M
In your Jenkins installation directory there is a jenkins.xml, where you can set various options. Add the parameter -Xmx with the size you want to the arguments-tag (or increase the size if its already there).
As wikipedia says, Median-of-Medians is theoretically o(N), but it is not used in practice because the overhead of finding "good" pivots makes it too slow.
http://en.wikipedia.org/wiki/Selection_algorithm
Here is Java source for a Quickselect algorithm to find the k'th element in an array:
/**
* Returns position of k'th largest element of sub-list.
*
* @param list list to search, whose sub-list may be shuffled before
* returning
* @param lo first element of sub-list in list
* @param hi just after last element of sub-list in list
* @param k
* @return position of k'th largest element of (possibly shuffled) sub-list.
*/
static int select(double[] list, int lo, int hi, int k) {
int n = hi - lo;
if (n < 2)
return lo;
double pivot = list[lo + (k * 7919) % n]; // Pick a random pivot
// Triage list to [<pivot][=pivot][>pivot]
int nLess = 0, nSame = 0, nMore = 0;
int lo3 = lo;
int hi3 = hi;
while (lo3 < hi3) {
double e = list[lo3];
int cmp = compare(e, pivot);
if (cmp < 0) {
nLess++;
lo3++;
} else if (cmp > 0) {
swap(list, lo3, --hi3);
if (nSame > 0)
swap(list, hi3, hi3 + nSame);
nMore++;
} else {
nSame++;
swap(list, lo3, --hi3);
}
}
assert (nSame > 0);
assert (nLess + nSame + nMore == n);
assert (list[lo + nLess] == pivot);
assert (list[hi - nMore - 1] == pivot);
if (k >= n - nMore)
return select(list, hi - nMore, hi, k - nLess - nSame);
else if (k < nLess)
return select(list, lo, lo + nLess, k);
return lo + k;
}
I have not included the source of the compare and swap methods, so it's easy to change the code to work with Object[] instead of double[].
In practice, you can expect the above code to be o(N).
A number of parameters affect generation size. The following diagram illustrates the difference between committed space and virtual space in the heap. At initialization of the virtual machine, the entire space for the heap is reserved. The size of the space reserved can be specified with the -Xmx
option. If the value of the -Xms
parameter is smaller than the value of the -Xmx
parameter, not all of the space that is reserved is immediately committed to the virtual machine. The uncommitted space is labeled "virtual" in this figure. The different parts of the heap (permanent generation, tenured generation and young generation) can grow to the limit of the virtual space as needed.
By default, the virtual machine grows or shrinks the heap at each collection to try to keep the proportion of free space to live objects at each collection within a specific range. This target range is set as a percentage by the parameters -XX:MinHeapFreeRatio=<minimum>
and -XX:MaxHeapFreeRatio=<maximum>
, and the total size is bounded below by -Xms<min>
and above by -Xmx<max>
.
Parameter Default Value
MinHeapFreeRatio 40
MaxHeapFreeRatio 70
-Xms 3670k
-Xmx 64m
Default values of heap size parameters on 64-bit systems have been scaled up by approximately 30%. This increase is meant to compensate for the larger size of objects on a 64-bit system.
With these parameters, if the percent of free space in a generation falls below 40%, the generation will be expanded to maintain 40% free space, up to the maximum allowed size of the generation. Similarly, if the free space exceeds 70%, the generation will be contracted so that only 70% of the space is free, subject to the minimum size of the generation.
Large server applications often experience two problems with these defaults. One is slow startup, because the initial heap is small and must be resized over many major collections. A more pressing problem is that the default maximum heap size is unreasonably small for most server applications. The rules of thumb for server applications are:
In general, increase the memory as you increase the number of processors, since allocation can be parallelized.
There is the full article
It seems that for 32-bit servers there is a JVM limitation that cannot be overcome (unless you find a special 32-bit JVM that does not impose a 2GB limit or less).
This thread on The Server Side has more details including several people who tested out various JVMs on 32-bit architectures. IBM's JVM seems to allow 100 more MB but that's not really going to get you what you want.
http://www.theserverside.com/discussions/thread.tss?thread_id=26347
The "real" solution is to use a 64-bit server with a 64-bit JVM to get heaps larger than 2GB per process. However, it's important to also consider the impact of increasing your address size (not just the addressable space) by using a 64-bit JVM. There will likely be performance and memory impacts for processing using less than 4GB of memory.
Food for thought: do each of these jobs really require 2GB of memory? Is there any way for the jobs to be modified to run within 1.8GB so this limit is not a problem?
The two forms are the same with one exception: temporarily, the new (Object *)
has an undefined value when the creation and assignment are separate. The compiler may combine them back together, since the undefined pointer is not particularly useful. This does not relate to global variables (unless the declaration is global, in which case it's still true for both forms).
In case if you would like to get the largest K element using max heap, you can do the following trick:
nums= [3,2,1,5,6,4]
k = 2 #k being the kth largest element you want to get
heapq.heapify(nums)
temp = heapq.nlargest(k, nums)
return temp[-1]
I found it hard to decipher what is meant by "working directory of the VM". In my example, I was using the Java Service Wrapper program to execute a jar - the dump files were created in the directory where I had placed the wrapper program, e.g. c:\myapp\bin. The reason I discovered this is because the files can be quite large and they filled up the hard drive before I discovered their location.
Start Android Studios with more heap memory:
export JAVA_OPTS="-Xms6144m -Xmx6144m -XX:NewSize=256m -XX:MaxNewSize=356m -XX:PermSize=256m -XX:MaxPermSize=356m"
open -a /Applications/Android\ Studio.app
In addition to looking for tools, consider looking for a likely culprit. Is there any component you're using, perhaps not written by you, which may not have been designed and tested to run in a multithreaded environment? Or simply one which you do not know has run in such an environment.
The last time it happened to me, it was a native package which had been successfully used from batch jobs for years. But it was the first time at this company that it had been used from a .NET web service (which is multithreaded). That was it - they had lied about the code being thread safe.
The on-heap store refers to objects that will be present in the Java heap (and also subject to GC). On the other hand, the off-heap store refers to (serialized) objects that are managed by EHCache, but stored outside the heap (and also not subject to GC). As the off-heap store continues to be managed in memory, it is slightly slower than the on-heap store, but still faster than the disk store.
The internal details involved in management and usage of the off-heap store aren't very evident in the link posted in the question, so it would be wise to check out the details of Terracotta BigMemory, which is used to manage the off-disk store. BigMemory (the off-heap store) is to be used to avoid the overhead of GC on a heap that is several Megabytes or Gigabytes large. BigMemory uses the memory address space of the JVM process, via direct ByteBuffers that are not subject to GC unlike other native Java objects.
Some of tips that may helps some one
fedora 20, php 5.5.18
public function testRead() {
$ri = new MediaItemReader(self::getMongoColl('Media'));
foreach ($ri->dataReader(10) as $data) {
// ...
}
}
public function dataReader($numOfItems) {
$cursor = $this->getStorage()->find()->limit($numOfItems);
// here is the first place where "zend_mm_heap corrupted" error occurred
// var_dump() inside foreach-loop and generator
var_dump($cursor);
foreach ($cursor as $data) {
// ...
// and this is the second place where "zend_mm_heap corrupted" error occurred
$data['Geo'] = [
// try to access [0] index that is absent in ['Geo']
'lon' => $data['Geo'][0],
'lat' => $data['Geo'][1]
];
// ...
// Generator is used !!!
yield $data;
}
}
using var_dummp() actually not an error, it was placed just for debugging and will be removed on production code. But real place where zend_mm_heap was happened is the second place.
In the following C# code
public void Method1()
{
int i = 4;
int y = 2;
class1 cls1 = new class1();
}
Here's how the memory is managed
Local Variables
that only need to last as long as the function invocation go in the stack. The heap is used for variables whose lifetime we don't really know up front but we expect them to last a while. In most languages it's critical that we know at compile time how large a variable is if we want to store it on the stack.
Objects (which vary in size as we update them) go on the heap because we don't know at creation time how long they are going to last. In many languages the heap is garbage collected to find objects (such as the cls1 object) that no longer have any references.
In Java, most objects go directly into the heap. In languages like C / C++, structs and classes can often remain on the stack when you're not dealing with pointers.
More information can be found here:
The difference between stack and heap memory allocation « timmurphy.org
and here:
Creating Objects on the Stack and Heap
This article is the source of picture above: Six important .NET concepts: Stack, heap, value types, reference types, boxing, and unboxing - CodeProject
but be aware it may contain some inaccuracies.
Asus Nexus 7 (2013) 32Gig: getMemoryClass()=192 maxMemory()=201326592
I made the mistake of prototyping my game on the Nexus 7, and then discovering it ran out of memory almost immediately on my wife's generic 4.04 tablet (memoryclass 48, maxmemory 50331648)
I'll need to restructure my project to load fewer resources when I determine memoryclass is low.
Is there a way in Java to see the current heap size? (I can see it clearly in the logCat when debugging, but I'd like a way to see it in code to adapt, like if currentheap>(maxmemory/2) unload high quality bitmaps load low quality
You can pass input as ["apple","orange"]
if you want to leave the method as it is.
It worked for me with a similar method signature.
The rgba() function can accept a single hex color as well decimal RGB values. For example, this would work just fine:
@mixin background-opacity($color, $opacity: 0.3) {
background: $color; /* The Fallback */
background: rgba($color, $opacity);
}
element {
@include background-opacity(#333, 0.5);
}
If you ever need to break the hex color into RGB components, though, you can use the red(), green(), and blue() functions to do so:
$red: red($color);
$green: green($color);
$blue: blue($color);
background: rgb($red, $green, $blue); /* same as using "background: $color" */
for PHP 7.3 / Ubuntu
sudo apt install php7.3-zip
for PHP 7.4
sudo apt install php7.4-zip
I spent half a day searching for answers to an identical "Illegal mix of collations" error with conflicts between utf8_unicode_ci and utf8_general_ci.
I found that some columns in my database were not specifically collated utf8_unicode_ci. It seems mysql implicitly collated these columns utf8_general_ci.
Specifically, running a 'SHOW CREATE TABLE table1' query outputted something like the following:
| table1 | CREATE TABLE `table1` (
`id` int(11) NOT NULL,
`col1` varchar(4) CHARACTER SET utf8 NOT NULL,
`col2` int(11) NOT NULL,
PRIMARY KEY (`col1`,`col2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci |
Note the line 'col1' varchar(4) CHARACTER SET utf8 NOT NULL does not have a collation specified. I then ran the following query:
ALTER TABLE table1 CHANGE col1 col1 VARCHAR(4) CHARACTER SET utf8
COLLATE utf8_unicode_ci NOT NULL;
This solved my "Illegal mix of collations" error. Hope this might help someone else out there.
app.run(use_reloader=True)
we can use this, use_reloader so every time we reload the page our code changes will be updated.
As the error message says, non-default argument til
should not follow default argument hgt
.
Changing order of parameters (function call also be adjusted accordingly) or making hgt
non-default parameter will solve your problem.
def a(len1, hgt=len1, til, col=0):
->
def a(len1, hgt, til, col=0):
UPDATE
Another issue that is hidden by the SyntaxError.
os.system
accepts only one string parameter.
def a(len1, hgt, til, col=0):
system('mode con cols=%s lines=%s' % (len1, hgt))
system('title %s' % til)
system('color %s' % col)
Further to previous answers, you should note that a column defined as VARCHARS(10) will store 10 bytes, not 10 characters unless you define it as VARCHAR2(10 CHAR)
[The OP's question seems to be number related... this is just in case anyone else has a similar issue]
Using only standard API, pass the string to a URL
object then convert it to a URI
object. This will accurately determine the validity of the URL according to the RFC2396 standard.
Example:
public boolean isValidURL(String url) {
try {
new URL(url).toURI();
} catch (MalformedURLException | URISyntaxException e) {
return false;
}
return true;
}
The best way I can think of to accomplish this is via sp_addlinkedserver. You need to make sure that whatever account you use to add the link (via sp_addlinkedsrvlogin) has permissions to the table you're joining, but then once the link is established, you can call the server by name, i.e.:
SELECT *
FROM server1table
INNER JOIN server2.database.dbo.server2table ON .....
Getting the element type the jQuery way:
var elementType = $(this).prev().prop('nodeName');
doing the same without jQuery
var elementType = this.previousSibling.nodeName;
Checking for specific element type:
var is_element_input = $(this).prev().is("input"); //true or false
According to the Oracle PLSQL language definition, a character literal can contain "any printable character in the character set". https://docs.oracle.com/cd/A97630_01/appdev.920/a96624/02_funds.htm#2876
@Robert Love's answer exhibits a best practice for readable code, but you can also just type in the linefeed character into the code. Here is an example from a Linux terminal using sqlplus
:
SQL> set serveroutput on
SQL> begin
2 dbms_output.put_line( 'hello' || chr(10) || 'world' );
3 end;
4 /
hello
world
PL/SQL procedure successfully completed.
SQL> begin
2 dbms_output.put_line( 'hello
3 world' );
4 end;
5 /
hello
world
PL/SQL procedure successfully completed.
Instead of the CHR( NN ) function you can also use Unicode literal escape sequences like u'\0085'
which I prefer because, well you know we are not living in 1970 anymore. See the equivalent example below:
SQL> begin
2 dbms_output.put_line( 'hello' || u'\000A' || 'world' );
3 end;
4 /
hello
world
PL/SQL procedure successfully completed.
For fair coverage I guess it is worth noting that different operating systems use different characters/character sequences for end of line handling. You've got to have a think about the context in which your program output is going to be viewed or printed, in order to determine whether you are using the right technique.
u'\000D\000A'
u'\000A'
u'\0085'
'<BR>'
'<br />'
// Get the focused element:
var $focused = $(':focus');
// No jQuery:
var focused = document.activeElement;
// Does the element have focus:
var hasFocus = $('foo').is(':focus');
// No jQuery:
elem === elem.ownerDocument.activeElement;
Which one should you use? quoting the jQuery docs:
As with other pseudo-class selectors (those that begin with a ":"), it is recommended to precede :focus with a tag name or some other selector; otherwise, the universal selector ("*") is implied. In other words, the bare
$(':focus')
is equivalent to$('*:focus')
. If you are looking for the currently focused element, $( document.activeElement ) will retrieve it without having to search the whole DOM tree.
The answer is:
document.activeElement
And if you want a jQuery object wrapping the element:
$(document.activeElement)
I got this problem on freeBSD. It seems lapack packages are missing, I solved it installing them (as root) with:
pkg install lapack
pkg install atlas-devel #not sure this is needed, but just in case
I imagine it could work on other system too using the appropriate package installer (e.g. apt-get)
I have a similar issue, have you tried:
proxy.ClientCredentials.Windows.AllowedImpersonationLevel =
System.Security.Principal.TokenImpersonationLevel.Impersonation;
use min-height
instead of height
Check out this plunkr.
When you're binding to variables, you need to use the brackets. Also, you use the hashtag when you want to get references to elements in your html, not for declaring variables inside of templates like that.
<md-button-toggle *ngFor="let indicador of indicadores; let first = first;" [value]="indicador.id" [checked]="first">
...
Edit: Thanks to Christopher Moore: Angular exposes the following local variables:
index
first
last
even
odd
If someone wants the answer, I think I just got it. Try this:
override func supportedInterfaceOrientations() -> UIInterfaceOrientationMask {
return UIInterfaceOrientationMask.Portrait.toRaw().hashValue | UIInterfaceOrientationMask.PortraitUpsideDown.toRaw().hashValue
}
Hope it helps !
EDIT :
To force rotation, use the following code :
let value = UIInterfaceOrientation.LandscapeRight.rawValue
UIDevice.currentDevice().setValue(value, forKey: "orientation")
It works for iOS 7 & 8 !
I confronted similar issue when I wanted to post image file to a rest API from Python (Not wechat API though). The solution for me was to use 'data' parameter to post the file in binary data instead of 'files'. Requests API reference
data = open('your_image.png','rb').read()
r = requests.post(your_url,data=data)
Hope this works for your case.
You could replace all spaces by an empty string, all comas by dots and then parse it.
var str = "110 000,23";
var num = parseFloat(str.replace(/\s/g, "").replace(",", "."));
console.log(num);
I used a regex in the first one to be able to match all spaces, not just the first one.
I would be using laravel whereDoesntHave to achieve this.
Customer::whereDoesntHave('orders')->get();
You are using a wrong overload of the Html.ActionLink
helper. What you think is routeValues
is actually htmlAttributes
! Just look at the generated HTML, you will see that this anchor's href property doesn't look as you expect it to look.
Here's what you are using:
@Html.ActionLink(
"Reply", // linkText
"BlogReplyCommentAdd", // actionName
"Blog", // routeValues
new { // htmlAttributes
blogPostId = blogPostId,
replyblogPostmodel = Model,
captchaValid = Model.AddNewComment.DisplayCaptcha
}
)
and here's what you should use:
@Html.ActionLink(
"Reply", // linkText
"BlogReplyCommentAdd", // actionName
"Blog", // controllerName
new { // routeValues
blogPostId = blogPostId,
replyblogPostmodel = Model,
captchaValid = Model.AddNewComment.DisplayCaptcha
},
null // htmlAttributes
)
Also there's another very serious issue with your code. The following routeValue:
replyblogPostmodel = Model
You cannot possibly pass complex objects like this in an ActionLink. So get rid of it and also remove the BlogPostModel
parameter from your controller action. You should use the blogPostId
parameter to retrieve the model from wherever this model is persisted, or if you prefer from wherever you retrieved the model in the GET action:
public ActionResult BlogReplyCommentAdd(int blogPostId, bool captchaValid)
{
BlogPostModel model = repository.Get(blogPostId);
...
}
As far as your initial problem is concerned with the wrong overload I would recommend you writing your helpers using named parameters:
@Html.ActionLink(
linkText: "Reply",
actionName: "BlogReplyCommentAdd",
controllerName: "Blog",
routeValues: new {
blogPostId = blogPostId,
captchaValid = Model.AddNewComment.DisplayCaptcha
},
htmlAttributes: null
)
Now not only that your code is more readable but you will never have confusion between the gazillions of overloads that Microsoft made for those helpers.
select region,sum(number) total
from
(
select region,number
from cash_table
union all
select region,number
from cheque_table
) t
group by region
You need to create /usr/local/include and /usr/local/lib if they don't exists:
$ sudo mkdir -p /usr/local/include
$ sudo chown -R $USER:admin /usr/local/include
In case dingbats/icon fonts are an option, you can use them instead of images.
The following uses a combination of

)
for the sign in logo),In HTML:
<link href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/css/bootstrap-combined.no-icons.min.css" rel="stylesheet">
<link href="//netdna.bootstrapcdn.com/font-awesome/3.2.1/css/font-awesome.css" rel="stylesheet">
<form name="signin" action="#" method="POST">
<input type="text" name="text-input" placeholder=" your username" class="stylish"/><br/>
<input type="submit" value=" sign in" class="stylish"/>
</form>
In CSS:
.stylish {
font-family: georgia, FontAwesome;
}
Notice the font-family
specification: all characters/code points will use georgia
, falling back to FontAwesome
for any code points georgia
doesn't provide characters for. georgia
doesn't provide any characters in the private use range, exactly where FontAwesome
has placed its icons.
EDIT:
As mentioned in a comment, My answer doesn't account for characters that need to be escaped like a ;
. You should use the accepted answer Darin made if your file name could contain a semi-colon.
Add a Response.AddHeader to set the file name
Response.AddHeader("Content-Disposition", "attachment; filename=*FILE_NAME*");
Just change FILE_NAME to the name of the file.
This is an old question, but I posted a comment in 2014 and frequently come back to this. I thought I would leave a full answer. This isn't the shortest solution but it is quite easy to understand.
Insert a new value into an associative array, at a numbered position, preserving keys, and preserving order.
$columns = array(
'id' => 'ID',
'name' => 'Name',
'email' => 'Email',
'count' => 'Number of posts'
);
$columns = array_merge(
array_slice( $columns, 0, 3, true ), // The first 3 items from the old array
array( 'subscribed' => 'Subscribed' ), // New value to add after the 3rd item
array_slice( $columns, 3, null, true ) // Other items after the 3rd
);
print_r( $columns );
/*
Array (
[id] => ID
[name] => Name
[email] => Email
[subscribed] => Subscribed
[count] => Number of posts
)
*/
this things is worked on laravel 5.1.
first, on your terminal execute this code
php artisan make:migration add_paid_to_users --table=users
after that go to your project directory and expand directory database - migration and edit file add_paid_to_users.php, add this code
public function up()
{
Schema::table('users', function (Blueprint $table) {
$table->string('paid'); //just add this line
});
}
after that go back to your terminal and execute this command
php artisan migrate
hope this help.
I do believe that
if (startDate <= date && date <= endDate) {
alert("Yay");
} else {
alert("Nay! :(");
}
works too...
class User(object):
email = 'none'
firstname = 'none'
lastname = 'none'
def __init__(self, email=None, firstname=None, lastname=None):
self.email = email
self.firstname = firstname
self.lastname = lastname
@classmethod
def print_var(cls, obj):
print ("obj.email obj.firstname obj.lastname")
print(obj.email, obj.firstname, obj.lastname)
print("cls.email cls.firstname cls.lastname")
print(cls.email, cls.firstname, cls.lastname)
u1 = User(email='abc@xyz', firstname='first', lastname='last')
User.print_var(u1)
In the above code, the User class has 3 global variables, each with value 'none'. u1 is the object created by instantiating this class. The method print_var prints the value of class variables of class User and object variables of object u1. In the output shown below, each of the class variables User.email
, User.firstname
and User.lastname
has value 'none'
, while the object variables u1.email
, u1.firstname
and u1.lastname
have values 'abc@xyz'
, 'first'
and 'last'
.
obj.email obj.firstname obj.lastname
('abc@xyz', 'first', 'last')
cls.email cls.firstname cls.lastname
('none', 'none', 'none')
Documentation for crypto: http://nodejs.org/api/crypto.html
const crypto = require('crypto')
const text = 'I love cupcakes'
const key = 'abcdeg'
crypto.createHmac('sha1', key)
.update(text)
.digest('hex')
Runtime.getCurrentRumtime().halt(0);
In my case the error was caused because I was typing
git push origin master
while I was on the develop branch try:
git push origin branchname
Hope this helps somebody
This answer applies to using gVim on Windows 10. I cannot guarantee the same results for other operating systems.
Add:
set nobackup
set noswapfile
set noundofile
To your _vimrc file.
Note: This is the direct answer to the question (for Windows 10) and probably not the safest thing to do (read the other answers), but this is the fastest solution in my case.
I used the answer of Steve Mallory, but I am affraid the timer never or at least sometimes does not go to 86400 nor 0 (zero) sharp (MS Access 2013). So I modified the code. I changed the midnight condition to "If Timer >= 86399 Then" and added the break of the loop "Exit Do" as follows:
Public Function Pause(NumberOfSeconds As Variant)
On Error GoTo Error_GoTo
Dim PauseTime As Variant
Dim Start As Variant
Dim Elapsed As Variant
PauseTime = NumberOfSeconds
Start = Timer
Elapsed = 0
Do While Timer < Start + PauseTime
Elapsed = Elapsed + 1
If Timer >= 86399
' Crossing midnight
' PauseTime = PauseTime - Elapsed
' Start = 0
' Elapsed = 0
Exit Do
End If
DoEvents
Loop
Exit_GoTo:
On Error GoTo 0
Exit Function
Error_GoTo:
Debug.Print Err.Number, Err.Description, Erl
GoTo Exit_GoTo
End Function
Yield has two great uses
It helps to provide custom iteration with out creating temp collections. ( loading all data and looping)
It helps to do stateful iteration. ( streaming)
Below is a simple video which i have created with full demonstration in order to support the above two points
neater:
function BlockID() {
return {
"s":"Images/Block_01.png",
"g":"Images/Block_02.png",
"C":"Images/Block_03.png",
"d":"Images/Block_04.png"
}
}
or just
var images = {
"s":"Images/Block_01.png",
"g":"Images/Block_02.png",
"C":"Images/Block_03.png",
"d":"Images/Block_04.png"
}
The string
constants may be what you want. (docs)
>>> import string >>> string.ascii_uppercase 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
If you want all printable characters:
>>> string.printable '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;?@[\\]^_`{|}~ \t\n\r\x0b\x0c'
hmm, well here's a workaround anyway:
function JSON_stringify(s, emit_unicode)
{
var json = JSON.stringify(s);
return emit_unicode ? json : json.replace(/[\u007f-\uffff]/g,
function(c) {
return '\\u'+('0000'+c.charCodeAt(0).toString(16)).slice(-4);
}
);
}
test case:
js>s='15\u00f8C 3\u0111';
15°C 3?
js>JSON_stringify(s, true)
"15°C 3?"
js>JSON_stringify(s, false)
"15\u00f8C 3\u0111"
As ping
works, but telnet
to port 80
does not, the HTTP port 80
is closed on your machine. I assume that your browser's HTTP connection goes through a proxy (as browsing works, how else would you read stackoverflow?).
You need to add some code to your python program, that handles the proxy, like described here:
Please note that soultions written above removes only space. If you want also to remove tab or new line use stri_replace_all_charclass
from stringi
package.
library(stringi)
stri_replace_all_charclass(" ala \t ma \n kota ", "\\p{WHITE_SPACE}", "")
## [1] "alamakota"
Same thing worked for me: Properties -> Java Build Path -> "Order and Export" Interestingly - why this is not done automatically? I guess some setting is missing. Also this happened for me after SDK upgrade.
This is so simple:
Create a drawable file with a gradient like this:
for shadow below a view below_shadow.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<gradient
android:startColor="#20000000"
android:endColor="@android:color/transparent"
android:angle="270" >
</gradient>
</shape>
for shadow above a view above_shadow.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<gradient
android:startColor="#20000000"
android:endColor="@android:color/transparent"
android:angle="90" >
</gradient>
</shape>
and so on for right and left shadow just change the angle of the gradient :)
Have you tried using some of the third party tools to do the search? There are several available out there that are free and that saved me a ton of time in the past.
Below are two SSMS Addins I used with good success.
ApexSQL Search – Searches both schema and data in databases and has additional features such as dependency tracking and more…
SSMS Tools pack – Has same search functionality as previous one and several other cool features. Not free for SQL Server 2012 but still very affordable.
I know this answer is not 100% related to the questions (which was more specific) but hopefully others will find this useful.
Bear in mind that 0
is a special case of parameter numbers inside a batch file, where 0
means this file as given on the command line.
So if the file is myfile.bat, you could call it in several ways as follows, each of which would give you a different output from the %0
or %~0
usage:
myfile
myfile.bat
mydir\myfile.bat
c:\mydir\myfile.bat
"c:\mydir\myfile.bat"
All of the above are legal calls if you call it from the correct relative place to the directory in which it exists. %~0
strips the quotes from the last example, whereas %0
does not.
Because these all give different results, %0
and %~0
are very unlikely to be what you actually want to use.
Here's a batch file to illustrate:
@echo Full path and filename: %~f0
@echo Drive: %~d0
@echo Path: %~p0
@echo Drive and path: %~dp0
@echo Filename without extension: %~n0
@echo Filename with extension: %~nx0
@echo Extension: %~x0
@echo Filename as given on command line: %0
@echo Filename as given on command line minus quotes: %~0
@REM Build from parts
@SETLOCAL
@SET drv=%~d0
@SET pth=%~p0
@SET fpath=%~dp0
@SET fname=%~n0
@SET ext=%~x0
@echo Simply Constructed name: %fpath%%fname%%ext%
@echo Fully Constructed name: %drv%%pth%%fname%%ext%
@ENDLOCAL
pause
if you follow
UPDATE table SET name = NULL
then name is "" not NULL IN MYSQL means your query
SELECT * FROM table WHERE name = NULL
not work or disappoint yourself
If you have multiple windows open and only want to close the one that was closed use JFrame.dispose().
If you want to close all windows and terminate the application use System.exit()
As noted by Mattias Nordqvist in the comments below, you can also select the radio button option "Run whether user is logged on or not". When saving the task, you will be prompted once for the user password. bambams noted that this wouldn't grant System permissions to the process, and also seems to hide the command window.
It's not an obvious solution, but to make a Scheduled Task run in the background, change the User running the task to "SYSTEM", and nothing will appear on your screen.
Declare
public static int[] locations={1,2,3};
outside of the main method.
You can try with
.appBackground {
position: relative;
background-image: url(".../img/background.jpg");
background-repeat:no-repeat;
background-size:100% 100vh;
}
works for me :)
I have encountered this problem as well. Here is my solution:
Below is the error while running a small Spring Application:-
*HTTP Status 500 -
--------------------------------------------------------------------------------
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: An exception occurred processing JSP page /WEB-INF/jsp/employe.jsp at line 12
9: <form:form method="POST" commandName="command" action="/SpringWeb/addEmploye">
10: <table>
11: <tr>
12: <td><form:label path="name">Name</form:label></td>
13: <td><form:input path="name" /></td>
14: </tr>
15: <tr>
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:568)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:465)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:238)
org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:250)
org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1060)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:798)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:716)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
root cause
java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'command' available as request attribute
org.springframework.web.servlet.support.BindStatus.<init>(BindStatus.java:141)
org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getBindStatus(AbstractDataBoundFormElementTag.java:174)
org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getPropertyPath(AbstractDataBoundFormElementTag.java:194)
org.springframework.web.servlet.tags.form.LabelTag.autogenerateFor(LabelTag.java:129)
org.springframework.web.servlet.tags.form.LabelTag.resolveFor(LabelTag.java:119)
org.springframework.web.servlet.tags.form.LabelTag.writeTagContent(LabelTag.java:89)
org.springframework.web.servlet.tags.form.AbstractFormTag.doStartTagInternal(AbstractFormTag.java:102)
org.springframework.web.servlet.tags.RequestContextAwareTag.doStartTag(RequestContextAwareTag.java:79)
org.apache.jsp.WEB_002dINF.jsp.employe_jsp._jspx_meth_form_005flabel_005f0(employe_jsp.java:185)
org.apache.jsp.WEB_002dINF.jsp.employe_jsp._jspx_meth_form_005fform_005f0(employe_jsp.java:120)
org.apache.jsp.WEB_002dINF.jsp.employe_jsp._jspService(employe_jsp.java:80)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:238)
org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:250)
org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1060)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:798)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:716)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.26 logs.*
In order to resolve this issue you need to do the following in the controller class:-
import org.springframework.web.portlet.ModelAndView;
"
to "import org.springframework.web.servlet.ModelAndView;
"...Update: Since ES6, you can simply use the spread syntax when calling the function:
func(...arr);
Since ES6 also if you expect to treat your arguments as an array, you can also use the spread syntax in the parameter list, for example:
function func(...args) {
args.forEach(arg => console.log(arg))
}
const values = ['a', 'b', 'c']
func(...values)
func(1, 2, 3)
And you can combine it with normal parameters, for example if you want to receive the first two arguments separately and the rest as an array:
function func(first, second, ...theRest) {
//...
}
And maybe is useful to you, that you can know how many arguments a function expects:
var test = function (one, two, three) {};
test.length == 3;
But anyway you can pass an arbitrary number of arguments...
The spread syntax is shorter and "sweeter" than apply
and if you don't need to set the this
value in the function call, this is the way to go.
Here is an apply example, which was the former way to do it:
var arr = ['a','b','c'];
function func() {
console.log(this); // 'test'
console.log(arguments.length); // 3
for(var i = 0; i < arguments.length; i++) {
console.log(arguments[i]);
}
};
func.apply('test', arr);
Nowadays I only recommend using apply
only if you need to pass an arbitrary number of arguments from an array and set the this
value. apply
takes is the this
value as the first arguments, which will be used on the function invocation, if we use null
in non-strict code, the this
keyword will refer to the Global object (window) inside func
, in strict mode, when explicitly using 'use strict' or in ES modules, null
will be used.
Also note that the arguments
object is not really an Array, you can convert it by:
var argsArray = Array.prototype.slice.call(arguments);
And in ES6:
const argsArray = [...arguments] // or Array.from(arguments)
But you rarely use the arguments
object directly nowadays thanks to the spread syntax.
File > Settings,
appearance
and select the theme of your choice from the dropdown.install themes
, they are the jar files
by File > Import Settings
, select the file or your choice and select ok
a pop up to restart
the studio
will open up click yes and studio will restart and your theme will be applied. I struggled with the same problem where I was trying to execute an update query like the same as you did-
@Modifying
@Transactional
@Query(value = "UPDATE SAMPLE_TABLE st SET st.status=:flag WHERE se.referenceNo in :ids")
public int updateStatus(@Param("flag")String flag, @Param("ids")List<String> references);
This will work if you have put @EnableTransactionManagement
annotation on the main class.
Spring 3.1 introduces the @EnableTransactionManagement
annotation to be used in on @Configuration
classes and enable transactional support.
1)
var merged = {};
for(key in obj1)
merged[key] = obj1[key];
for(key in obj2)
merged[key] = obj2[key];
2)
var merged = {};
Object.keys(obj1).forEach(k => merged[k] = obj1[k]);
Object.keys(obj2).forEach(k => merged[k] = obj2[k]);
Object.keys(obj1)
.concat(Object.keys(obj2))
.forEach(k => merged[k] = k in obj2 ? obj2[k] : obj1[k]);
3) Simplest way:
var merged = {};
Object.assign(merged, obj1, obj2);
From what I understand of your request, this should work:
<script>
// var status = document.getElementsByID("uniqueID"); // this works too
var status = document.getElementsByName("status")[0];
var jsonArr = [];
for (var i = 0; i < status.options.length; i++) {
jsonArr.push({
id: status.options[i].text,
optionValue: status.options[i].value
});
}
</script>
There is no hard and fast rule.
Here are some rules to make code thread safe in .NET and why these are not good rules:
lock
on a common thing. All locks must be done in same order. This will make the code thread safe, but it will be incredibly slow, and you might as well not use multiple threads.There is no rule that makes the code thread safe, the only thing you can do is make sure that your code will work no matter how many times is it being actively executed, each thread can be interrupted at any point, with each thread being in its own state/location, and this for each function (static or otherwise) that is accessing common objects.
That query is failing and returning false
.
Put this after mysqli_query()
to see what's going on.
if (!$check1_res) {
printf("Error: %s\n", mysqli_error($con));
exit();
}
For more information:
These are the steps to follow when you want your PHP application to be installed on a LAN server (not on web)
Note: If firewall is installed, ensure that you add the http port 80 and 8080 to exceptions and allow to listen. Go to Control Panel>Windows Firewall>Allow a program to communicate through windows firewall>Add another program Name: http Port: 80 Add one more as http - 8080
If IIS (Microsoft .Net Application Internet Information Server) is installed with any Microsoft .Net application already on server, then it would have already occupied 80 port. In that case change the #Listen 192.168.1.193:80 to #Listen 192.168.1.193:8080
Hope this helps! :)
The first thing you should try is:
sudo pip uninstall pip
On many environments that doesn't work. So given the lack of info on that problem, I ended up removing pip manually from /usr/local/bin.
Just use an <a>
by itself, set it to display: block;
and set width
and height
. Get rid of the <span>
and <div>
. This is the semantic way to do it. There is no need to wrap things in <divs>
(or any element) for layout. That is what CSS is for.
Demo: http://jsfiddle.net/ThinkingStiff/89Enq/
HTML:
<a id="music" href="Music.html">Music I Like</a>
CSS:
#music {
background-color: black;
color: white;
display: block;
height: 40px;
line-height: 40px;
text-decoration: none;
width: 100px;
text-align: center;
}
Output:
This works great if a straight copy is in order. If the situation calls for creating new objects from templates, I usually wrap the template div in a hidden storage div and use jquery's html() in conjunction with clone() applying the following technique:
<style>
#element-storage {
display: none;
top: 0;
right: 0;
position: fixed;
width: 0;
height: 0;
}
</style>
<script>
$("#new-div").append($("#template").clone().html(function(index, oldHTML){
// .. code to modify template, e.g. below:
var newHTML = "";
newHTML = oldHTML.replace("[firstname]", "Tom");
newHTML = newHTML.replace("[lastname]", "Smith");
// newHTML = newHTML.replace(/[Example Replace String]/g, "Replacement"); // regex for global replace
return newHTML;
}));
</script>
<div id="element-storage">
<div id="template">
<p>Hello [firstname] [lastname]</p>
</div>
</div>
<div id="new-div">
</div>
Try testing for DOM
element
if (!!$(selector)[0]) // do stuff
When you checkout to a commit git checkout <commit-hash>
or to a remote branch your HEAD will get detached and try to create a new commit on it.
Commits that are not reachable by any branch or tag will be garbage collected and removed from the repository after 30 days.
Another way to solve this is by creating a new branch for the newly created commit and checkout to it. git checkout -b <branch-name> <commit-hash>
This article illustrates how you can get to detached HEAD state.
I've no idea why the other two answers are so popular!
I believe you were right in assuming the ORM framework should handle it - after all, that is what it promises to deliver. Otherwise your domain model gets corrupted by persistence concerns. NHibernate manages this happily if you setup the cascade settings correctly. In Entity Framework it is also possible, they just expect you to follow better standards when setting up your database model, especially when they have to infer what cascading should be done:
You have to define the parent - child relationship correctly by using an "identifying relationship".
If you do this, Entity Framework knows the child object is identified by the parent, and therefore it must be a "cascade-delete-orphans" situation.
Other than the above, you might need to (from NHibernate experience)
thisParent.ChildItems.Clear();
thisParent.ChildItems.AddRange(modifiedParent.ChildItems);
instead of replacing the list entirely.
UPDATE
@Slauma's comment reminded me that detached entities are another part of the overall problem. To solve that, you can take the approach of using a custom model binder that constructs your models by attempting to load it from the context. This blog post shows an example of what I mean.
Add this to your external style sheet (preferred):
a {text-decoration:none;}
Or add this to the <head>
of your HTML document:
<style type="text/css">
a {text-decoration:none;}
</style>
Or add it to the a
element itself (not recommended):
<!-- Add [ style="text-decoration:none;"] -->
<a href="http://example.com" style="text-decoration:none;">Text</a>
You could make use of Prepared Stements
like this.
set @query = concat( "select name from " );
set @query = concat( "table_name"," [where condition] " );
prepare stmt from @like_q;
execute stmt;
the safest way is to put the ! for the regex negation within the [[ ]]
like this:
if [[ ! ${STR} =~ YOUR_REGEX ]]; then
otherwise it might fail on certain systems.
For those wanting the box-shadow on the col-*
container itself and not on the .container
, you can add another div
just inside the col-*
element, and add the shadow to that. This element will not have the padding, and therefor not interfere.
The first image has the box-shadow
on the col-*
element. Because of the 15px padding on the col
element, the shadow is pushed to the outside of the div
element rather than on the visual edges of it.
<div class="col-md-4" style="box-shadow: 0px 2px 25px rgba(0, 0, 0, .25);">
<div class="thumbnail">
{!! HTML::image('images/sampleImage.png') !!}
</div>
</div>
The second image has a wrapper div
with the box-shadow
on it. This will place the box-shadow
on the visual edges of the element.
<div class="col-md-4">
<div id="wrapper-div" style="box-shadow: 0px 2px 25px rgba(0, 0, 0, .25);">
<div class="thumbnail">
{!! HTML::image('images/sampleImage.png') !!}
</div>
</div>
</div>
We can resolve this warning by adding this code below in Strings.xml and activity_main.xml
<string name="imgDescription">Background Picture</string>
you image will be like that:
<ImageView
android:id="@+id/imageView2"
android:lay`enter code hereout_width="0dp"
android:layout_height="wrap_content"
android:contentDescription="@string/imgDescription"
app:layout_editor_absoluteX="0dp"
app:layout_editor_absoluteY="0dp"
app:srcCompat="@drawable/background1"
tools:layout_editor_absoluteX="0dp"
tools:layout_editor_absoluteY="0dp" />
android:contentDescription="@string/imgDescription"
Strings.xml
<resources>
<string name="app_name">Saini_Browser</string>
<string name="SainiBrowser">textView2</string>
<string name="imgDescription">BackGround Picture</string>
</resources>
Use:
Create a batch file
Copy the below text into the batch file
set folder="C:\test"
cd /d %folder%
for /F "delims=" %%i in ('dir /b') do (rmdir "%%i" /s/q || del "%%i" /s/q)
It will delete all files and folders.
New, expanded answer to an old, commonly asked question...
minOccurs
and maxOccurs
default to 1
.<xsd:element name="A"/>
means A
is required and must appear exactly once.
<xsd:element name="A" minOccurs="0"/>
means A
is optional and may appear at most once.
<xsd:element name="A" maxOccurs="unbounded"/>
means A
is required and may repeat an unlimited number of times.
<xsd:element name="A" minOccurs="0" maxOccurs="unbounded"/>
means A
is optional and may repeat an unlimited number of times.
In general, an element is required to appear when the value of minOccurs is 1 or more. The maximum number of times an element may appear is determined by the value of a maxOccurs attribute in its declaration. This value may be a positive integer such as 41, or the term unbounded to indicate there is no maximum number of occurrences. The default value for both the minOccurs and the maxOccurs attributes is 1. Thus, when an element such as comment is declared without a maxOccurs attribute, the element may not occur more than once. Be sure that if you specify a value for only the minOccurs attribute, it is less than or equal to the default value of maxOccurs, i.e. it is 0 or 1. Similarly, if you specify a value for only the maxOccurs attribute, it must be greater than or equal to the default value of minOccurs, i.e. 1 or more. If both attributes are omitted, the element must appear exactly once.
W3C XML Schema Part 1: Structures Second Edition
<element
maxOccurs = (nonNegativeInteger | unbounded) : 1
minOccurs = nonNegativeInteger : 1
>
</element>
To tell the truth...you have to make the decision as to which is the better language. I know what I can do with C#. I know what can be done in C++. C# isn't made to do what C++ was made to do...write code at the most basic level and still be somewhat meaningful when read by human eyes.
We are developing a game engine with C#, DirectX...is it a challenge? hell yeah...but it's something we chose to do. We are looking at some performance levels that are very close to what C++ can give. So, I see no problems with this effort.
To cross-platform development, if it weren't for .Net, we might not have the Mono platform. The Mono platform has broadened our platform base.
Here is some support to my arguments...
Check this code :
import java.util.Scanner;
public class Main {
public static void main(String[] args) throws IllegalAccessException {
String username ;
String password;
String yes_0r_no;
String scann;
String passscan;
Scanner scan = new Scanner(System.in);
Scanner scanner = new Scanner(System.in);
Scanner name = new Scanner(System.in);
System.out.println("Username:");
username = name.next().toLowerCase();
Scanner pass = new Scanner(System.in);
System.out.println("Password:");
password = pass.next().toLowerCase();
System.out.println("You are logged in");
Scanner ask = new Scanner(System.in);
System.out.println("Do you want to check this or not(yes or no) :");
yes_0r_no = ask.next().toLowerCase();
while (true){
if (yes_0r_no.equals("yes")){
System.out.println("Username:");
scann = scan.next().toLowerCase();
if (scann == username) {
continue;
}
System.out.println("Password");
passscan = scanner.next().toLowerCase();
if (passscan.equals(password)) {
System.out.println("You are logged in");
break;
}if (!password.equals(passscan)) {
throw new IllegalAccessException();
}
}
if (yes_0r_no.equals("no"))
break ;
}
}
}
Just add the following to your html code (withing the <head>
) and you are done.
HTML:
<style>
tr:nth-of-type(odd) {
background-color:#ccc;
}
</style>
Easier and faster than jQuery examples.
I do not work with google android but I think you'll find it's not that hard to get this working. If you read the relevant bit of the java tutorial you'll see that a registered cookiehandler gets callbacks from the HTTP code.
So if there is no default (have you checked if CookieHandler.getDefault()
really is null?) then you can simply extend CookieHandler, implement put/get and make it work pretty much automatically. Be sure to consider concurrent access and the like if you go that route.
edit: Obviously you'd have to set an instance of your custom implementation as the default handler through CookieHandler.setDefault()
to receive the callbacks. Forgot to mention that.
I had a similar problem where Xcode would spend lots of time indexing and would frequently hang building the project, at which point I had to force-quit and relaunch Xcode. It was very annoying.
Then I noticed a warning in the project about improperly assigning self
as a delegate. Sure enough, there was a missing protocol in the class declaration. Note that there is a similar assignment in the OP's sample code (though it is impossible to tell from the sample whether the correct protocol is declared):
leaderboardController.leaderboardDelegate == self;
After resolving that warning (by correctly declaring the implemented protocol), Xcode stopped misbehaving. Also, I should note that the project did execute correctly since the protocol methods were implemented. It was just that Xcode could not confirm that the protocol should in fact implemented by the class.
You can use mysqlcheck
to do this at the command line.
One database:
mysqlcheck -o <db_schema_name>
All databases:
mysqlcheck -o --all-databases
This is my solution
var cells = Array.prototype.slice.call(document.getElementById("tableI").getElementsByTagName("td"));
for(var i in cells){
console.log("My contents is \"" + cells[i].innerHTML + "\"");
}
You could extend the javascript Date object like this
Date.prototype.addDays = function(days) {
this.setDate(this.getDate() + parseInt(days));
return this;
};
and in your javascript code you could call
var currentDate = new Date();
// to add 4 days to current date
currentDate.addDays(4);
With pure JavaScript:
console.log(window.location.href)
Using Angular:
this.router.url
import { Component } from '@angular/core';
import { Router } from '@angular/router';
@Component({
template: 'The href is: {{href}}'
/*
Other component settings
*/
})
export class Component {
public href: string = "";
constructor(private router: Router) {}
ngOnInit() {
this.href = this.router.url;
console.log(this.router.url);
}
}
The plunkr is here: https://plnkr.co/edit/0x3pCOKwFjAGRxC4hZMy?p=preview
For this you can use CSS3 background-size
property. Write like this:
#div2{
background-image:url(http://s7.static.hootsuite.com/3-0-48/images/themes/classic/streams/message-gradient.png);
-moz-background-size:100% 100%;
-webkit-background-size:100% 100%;
background-size:100% 100%;
height:180px;
width:200px;
border: 1px solid red;
}
Check this: http://jsfiddle.net/qdzaw/1/
This might work. This Code dynamically appends the <script>
tag to the head
of the html file on button clicked.
const url = 'http://iknow.com/this/does/not/work/either/file.js';
export class MyAppComponent {
loadAPI: Promise<any>;
public buttonClicked() {
this.loadAPI = new Promise((resolve) => {
console.log('resolving promise...');
this.loadScript();
});
}
public loadScript() {
console.log('preparing to load...')
let node = document.createElement('script');
node.src = url;
node.type = 'text/javascript';
node.async = true;
node.charset = 'utf-8';
document.getElementsByTagName('head')[0].appendChild(node);
}
}
Simple One
Note: dont use display:none instead use opacity to hide and show
var menu= document.querySelector('.context_menu');
document.addEventListener("contextmenu", function(e) {
e.preventDefault();
menu.style.position = 'absolute';
menu.style.left = e.pageX + 'px';
menu.style.top = e.pageY + 'px';
menu.style.opacity = 1;
});
document.addEventListener("click", function(e){
if(e.target.closest('.context_menu'))
return;
menu.style.opacity = 0;
});
_x000D_
.context_menu{
width:70px;
background:lightgrey;
padding:5px;
opacity :0;
}
.context_menu div{
margin:5px;
background:grey;
}
.context_menu div:hover{
margin:5px;
background:red;
cursor:pointer;
}
_x000D_
<div class="context_menu">
<div>menu 1</div>
<div>menu 2</div>
</div>
_x000D_
extra css
var menu= document.querySelector('.context_menu');
document.addEventListener("contextmenu", function(e) {
e.preventDefault();
menu.style.position = 'absolute';
menu.style.left = e.pageX + 'px';
menu.style.top = e.pageY + 'px';
menu.style.opacity = 1;
});
document.addEventListener("click", function(e){
if(e.target.closest('.context_menu'))
return;
menu.style.opacity = 0;
});
_x000D_
.context_menu{
width:120px;
background:white;
border:1px solid lightgrey;
opacity :0;
}
.context_menu div{
padding:5px;
padding-left:15px;
margin:5px 2px;
border-bottom:1px solid lightgrey;
}
.context_menu div:last-child {
border:none;
}
.context_menu div:hover{
background:lightgrey;
cursor:pointer;
}
_x000D_
<div class="context_menu">
<div>menu 1</div>
<div>menu 2</div>
<div>menu 3</div>
<div>menu 4</div>
</div>
_x000D_
package test.concurrent;
public class DeadLockTest {
private static long sleepMillis;
private final Object lock1 = new Object();
private final Object lock2 = new Object();
public static void main(String[] args) {
sleepMillis = Long.parseLong(args[0]);
DeadLockTest test = new DeadLockTest();
test.doTest();
}
private void doTest() {
Thread t1 = new Thread(new Runnable() {
public void run() {
lock12();
}
});
Thread t2 = new Thread(new Runnable() {
public void run() {
lock21();
}
});
t1.start();
t2.start();
}
private void lock12() {
synchronized (lock1) {
sleep();
synchronized (lock2) {
sleep();
}
}
}
private void lock21() {
synchronized (lock2) {
sleep();
synchronized (lock1) {
sleep();
}
}
}
private void sleep() {
try {
Thread.sleep(sleepMillis);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
To run the deadlock test with sleep time 1 millisecond:
java -cp . test.concurrent.DeadLockTest 1
You Could do something like this .....
Your Table
CREATE TABLE TestTable
(
ID INT,
Data NVARCHAR(50)
)
GO
INSERT INTO TestTable
VALUES (1,'AABBCC'),
(2,'FFDD'),
(3,'TTHHJJKKLL')
GO
SELECT * FROM TestTable
My Suggestion
CREATE TABLE #DestinationTable
(
ID INT,
Data NVARCHAR(50)
)
GO
SELECT * INTO #Temp FROM TestTable
DECLARE @String NVARCHAR(2)
DECLARE @Data NVARCHAR(50)
DECLARE @ID INT
WHILE EXISTS (SELECT * FROM #Temp)
BEGIN
SELECT TOP 1 @Data = DATA, @ID = ID FROM #Temp
WHILE LEN(@Data) > 0
BEGIN
SET @String = LEFT(@Data, 2)
INSERT INTO #DestinationTable (ID, Data)
VALUES (@ID, @String)
SET @Data = RIGHT(@Data, LEN(@Data) -2)
END
DELETE FROM #Temp WHERE ID = @ID
END
SELECT * FROM #DestinationTable
Result Set
ID Data
1 AA
1 BB
1 CC
2 FF
2 DD
3 TT
3 HH
3 JJ
3 KK
3 LL
DROP Temp Tables
DROP TABLE #Temp
DROP TABLE #DestinationTable
Here is a totally out of the box solution.
In the ahk script, a) Ftp the commands (.ksh) file to the linux machine
b) Use plink like below. Plink should be installed if you have putty.
plink sessionname -l username -pw password test.ksh
or
plink -ssh example.com -l username -pw password test.ksh
All the steps will be performed in sequence whenever you press F9 in windows.
By loading the .js
file first and then calling the function via onclick, there's less coding and it's fairly obvious what's going on. We'll call the JS file zipcodehelp.js
.
HTML:
<!DOCTYPE html>
<html>
<head>
<title>Button to call JS function.</title>
</head>
<body>
<h1>Use Button to execute function in '.js' file.</h1>
<script type="text/javascript" src="zipcodehelp.js"></script>
<button onclick="ZipcodeHelp();">Get Zip Help!</button>
</body>
</html>
And the contents of zipcodehelp.js
is :
function ZipcodeHelp() {
alert("If Zipcode is missing in list at left, do: \n\n\
1. Enter any zipcode and click Create Client. \n\
2. Goto Zipcodes and create new zip code. \n\
3. Edit this new client from the client list.\n\
4. Select the new zipcode." );
}
Hope that helps! Cheers!
–Ken
Here's what I've used in past projects:
var myDate = new Date();
var tzo = (myDate.getTimezoneOffset()/60)*(-1);
//get server date value here, the parseInvariant is from MS Ajax, you would need to do something similar on your own
myDate = new Date.parseInvariant('<%=DataCurrentDate%>', 'yyyyMMdd hh:mm:ss');
myDate.setHours(myDate.getHours() + tzo);
//here you would have to get a handle to your span / div to set. again, I'm using MS Ajax's $get
var dateSpn = $get('dataDate');
dateSpn.innerHTML = myDate.localeFormat('F');
You can use CSS3 font-face
or webfonts
@font-face usage
@font-face {
font-family: Delicious;
src: url('Delicious-Roman.otf');
}
webfonts
take a look at Google Webfonts, http://www.google.com/webfonts
That image you linked to was for density curves, not histograms.
If you've been reading on ggplot then maybe the only thing you're missing is combining your two data frames into one long one.
So, let's start with something like what you have, two separate sets of data and combine them.
carrots <- data.frame(length = rnorm(100000, 6, 2))
cukes <- data.frame(length = rnorm(50000, 7, 2.5))
# Now, combine your two dataframes into one.
# First make a new column in each that will be
# a variable to identify where they came from later.
carrots$veg <- 'carrot'
cukes$veg <- 'cuke'
# and combine into your new data frame vegLengths
vegLengths <- rbind(carrots, cukes)
After that, which is unnecessary if your data is in long format already, you only need one line to make your plot.
ggplot(vegLengths, aes(length, fill = veg)) + geom_density(alpha = 0.2)
Now, if you really did want histograms the following will work. Note that you must change position from the default "stack" argument. You might miss that if you don't really have an idea of what your data should look like. A higher alpha looks better there. Also note that I made it density histograms. It's easy to remove the y = ..density..
to get it back to counts.
ggplot(vegLengths, aes(length, fill = veg)) +
geom_histogram(alpha = 0.5, aes(y = ..density..), position = 'identity')
You can set the path variable for easily by command prompt.
Open run and write cmd
In the command window write the following: set path=%path%;C:\python36
Try the below code , which takes care of the DST part as well.
if [ $(date +%w) -eq $(date -u +%w) ]; then
tz=$(( 10#$gmthour - 10#$localhour ))
else
tz=$(( 24 - 10#$gmthour + 10#$localhour ))
fi
echo $tz
myTime=`TZ=GMT+$tz date +'%Y%m%d'`
Courtsey Ansgar Wiechers
With python-varname
you can easily do it:
pip install python-varname
from varname import Wrapper
foo = Wrapper(True)
bar = Wrapper(False)
your_dict = {val.name: val.value for val in (foo, bar)}
print(your_dict)
# {'foo': True, 'bar': False}
Disclaimer: I'm the author of that python-varname library.
NSDate
is a specific point in time without a time zone. Think of it as the number of seconds that have passed since a reference date. How many seconds have passed in one time zone vs. another since a particular reference date? The answer is the same.
Depending on how you output that date (including looking at the debugger), you may get an answer in a different time zone.
If they ran at the same moment, the values of these are the same. They're both the number of seconds since the reference date, which may be formatted on output to UTC or local time. Within the date variable, they're both UTC.
Objective-C:
NSDate *UTCDate = [NSDate date]
Swift:
let UTCDate = NSDate.date()
To explain this, we can use a NSDateFormatter in a playground:
import UIKit
let date = NSDate.date()
// "Jul 23, 2014, 11:01 AM" <-- looks local without seconds. But:
var formatter = NSDateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss ZZZ"
let defaultTimeZoneStr = formatter.stringFromDate(date)
// "2014-07-23 11:01:35 -0700" <-- same date, local, but with seconds
formatter.timeZone = NSTimeZone(abbreviation: "UTC")
let utcTimeZoneStr = formatter.stringFromDate(date)
// "2014-07-23 18:01:41 +0000" <-- same date, now in UTC
The date output varies, but the date is constant. This is exactly what you're saying. There's no such thing as a local NSDate.
As for how to get microseconds out, you can use this (put it at the bottom of the same playground):
let seconds = date.timeIntervalSince1970
let microseconds = Int(seconds * 1000) % 1000 // chops off seconds
To compare two dates, you can use date.compare(otherDate)
.
dir=/home/smith/Desktop/Test
parentdir="$(dirname "$dir")"
Works if there is a trailing slash, too.
We could make that not so easy by hiding context menu, like this:
<video oncontextmenu="return false;" controls>
<source src="https://yoursite.com/yourvideo.mp4" >
</video>
Floating point numbers only have so many significant digits, but they can go much higher. If your app will ever handle large numbers, you will notice the epsilon value should be different.
0.001+0.001 = 0.002 BUT 12,345,678,900,000,000,000,000+1=12,345,678,900,000,000,000,000 if you are using floating point and double. It's not a good representation of money, unless you are damn sure you'll never handle more than a million dollars in this system.
I was able to track this down to the fact that the binaries that rvm
downloads do not play nice with OS X's OpenSSL, which is old and is no longer used by the OS.
The solution for me was to force compilation when installing Ruby via rvm
:
rvm reinstall --disable-binary 2.2
There seem to be something quirky with the 'automatic' entitlements in Xcode 4.6.
There is an Entitlement.plist file for each SDK at:
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/Entitlements.plist
A workaround solution I came up with was to edit this file and add the sneaky aps-environment key manually like so:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>application-identifier</key>
<string>$(AppIdentifierPrefix)$(CFBundleIdentifier)</string>
<key>aps-environment</key>
<string>development</string>
<key>keychain-access-groups</key>
<array>
<string>$(AppIdentifierPrefix)$(CFBundleIdentifier)</string>
</array>
</dict>
</plist>
Then, Xcode is generating correct Xcent file, which contains the aps-environment key at:
/Users/mySelf/Library/Developer/Xcode/DerivedData/myApp-buauvgusocvjyjcwdtpewdzycfmc/Build/Intermediates/myApp.build/Debug-iphoneos/myApp.build/myApp.xcent
You can locate where your Xcent file is created using Xcode's Log Navigator,
look for "ProcessProductPackaging".
Unfortunately, this is the only way I found that fixes the issue.
(and finally able to properly get push token now)
Just wondering if another more elegant solution is available.
Please see my SO question for more details on that:
Xcode 4.6 automatic entitlement not working - "no valid aps-environment"
If you are expecting 4
as output then try this:
char a[]={0x00,0xdc,0x01,0x04};
try this : here select is your select element
let select = document.getElementsByClassName('lstSelected')[0],
options = select.options,
len = options.length,
data='',
i=0;
while (i<len){
if (options[i].selected)
data+= "&" + select.name + '=' + options[i].value;
i++;
}
return data;
Data is in the form of query string i.e.name=value&name=anotherValue
Use the ArrayList copy constructor, then sort that.
List oldList;
List newList = new ArrayList(oldList);
Collections.sort(newList);
After making the copy, any changes to newList do not affect oldList.
Note however that only the references are copied, so the two lists share the same objects, so changes made to elements of one list affect the elements of the other.
Other answers posted here for this question did not work for me using the latest Visual Studio 2017 Enterprise edition (as of 2018-09-18).
Instead, I used this method:
Once installed, close and restart Visual Studio. Go to File->New Project and search for the word Installer. You'll know you have the correct templates installed if you see a list that looks something like this:
std::hex
is defined in <ios>
which is included by <iostream>
. But to use things like std::setprecision/std::setw/std::setfill
/etc you have to include <iomanip>
.
String
is a special built-in class of the language. It is for the String
class only in which you should avoid saying
String s = new String("Polish");
Because the literal "Polish"
is already of type String
, and you're creating an extra unnecessary object. For any other class, saying
CaseInsensitiveString cis = new CaseInsensitiveString("Polish");
is the correct (and only, in this case) thing to do.
This is how I solved this problem
$scope.downloadPDF = function () {
var link = document.createElement("a");
link.setAttribute("href", "path_to_pdf_file/pdf_filename.pdf");
link.setAttribute("download", "download_name.pdf");
document.body.appendChild(link); // Required for FF
link.click(); // This will download the data file named "download_name.pdf"
}
You can able to download Xcode DMG file from the
You can use template module to copy if script exists on local machine to remote machine and execute it.
- name: Copy script from local to remote machine
hosts: remote_machine
tasks:
- name: Copy script to remote_machine
template: src=script.sh.2 dest=<remote_machine path>/script.sh mode=755
- name: Execute script on remote_machine
script: sh <remote_machine path>/script.sh
Long story short, it probably doesn't matter. Use whichever you think looks nicest.
Longer answer, using Oracle's Java 7 JDK specifically, since this isn't defined at the JLS:
String.valueOf
or Character.toString
work the same way, so use whichever you feel looks nicer. In fact, Character.toString
simply calls String.valueOf
(source).
So the question is, should you use one of those or String.substring
. Here again it doesn't matter much. String.substring
uses the original string's char[]
and so allocates one object fewer than String.valueOf
. This also prevents the original string from being GC'ed until the one-character string is available for GC (which can be a memory leak), but in your example, they'll both be available for GC after each iteration, so that doesn't matter. The allocation you save also doesn't matter -- a char[1]
is cheap to allocate, and short-lived objects (as the one-char string will be) are cheap to GC, too.
If you have a large enough data set that the three are even measurable, substring
will probably give a slight edge. Like, really slight. But that "if... measurable" contains the real key to this answer: why don't you just try all three and measure which one is fastest?
In Microsoft SQL Server Management Studio (the admin tool for MSSQL) just go into "design" on a table and drag the column to the new position. Not command line but you can do it.
If you are using github and have enabled 2 factor authentication, you need to enter a Personal access token instead of your password
First reset your password:
git config --global --unset user.password
Then, log to your github account, on the right hand corner, click on Settings, then Developer Settings. Generate a Personal access token. Copy it.
git push
The terminal will prompt you for your username: enter your email address.
At the password prompt, enter the personal access token instead.
After several hours of test and research over the Internet, I've finally found how to start my PowerShell script with task scheduler, thanks to the video Scheduling a PowerShell Script using Windows Task Scheduler by Jack Fruh @sharepointjack.
Program/script -> put full path through powershell.exe
C:\WINDOWS\system32\WindowsPowerShell\v1.0\powershell.exe
Add arguments -> Full path to the script, and the script, without any " ".
Start in (optional) -> The directory where your script resides, without any " ".
On Android Studio you can use Device File Explorer
to view /data/data/my_app_package/cache.
Click View > Tool Windows > Device File Explorer
or click the Device File Explorer
button in the tool window bar to open the Device File Explorer.
In matplotlib it would be:
import matplotlib.pyplot as plt
data = [(0, 6.0705199999997801e-08), (1, 2.1015700100300739e-08),
(2, 7.6280656623374823e-09), (3, 5.7348209304555086e-09),
(4, 3.6812203579604238e-09), (5, 4.1572516753310418e-09)]
x_val = [x[0] for x in data]
y_val = [x[1] for x in data]
print x_val
plt.plot(x_val,y_val)
plt.plot(x_val,y_val,'or')
plt.show()
which would produce:
I have written a pretty fast method in c# which beats the hell out of the Regex. It is hosted in an article on CodeProject.
Its advantages are, among better performance the ability to replace named and numbered HTML entities (those like &amp;
and &203;
) and comment blocks replacement and more.
Please read the related article on CodeProject.
Thank you.
The curly braces are used only for import when export is named. If the export is default then curly braces are not used for import.
You can use this code for generating has code for a given string.
int hash = 7;
for (int i = 0; i < strlen; i++) {
hash = hash*31 + charAt(i);
}
It's just a function. Import it and call it:
import myModule
myModule.main()
If you need to parse arguments, you have two options:
Parse them in main()
, but pass in sys.argv
as a parameter (all code below in the same module myModule
):
def main(args):
# parse arguments using optparse or argparse or what have you
if __name__ == '__main__':
import sys
main(sys.argv[1:])
Now you can import and call myModule.main(['arg1', 'arg2', 'arg3'])
from other another module.
Have main()
accept parameters that are already parsed (again all code in the myModule
module):
def main(foo, bar, baz='spam'):
# run with already parsed arguments
if __name__ == '__main__':
import sys
# parse sys.argv[1:] using optparse or argparse or what have you
main(foovalue, barvalue, **dictofoptions)
and import and call myModule.main(foovalue, barvalue, baz='ham')
elsewhere and passing in python arguments as needed.
The trick here is to detect when your module is being used as a script; when you run a python file as the main script (python filename.py
) no import
statement is being used, so python calls that module "__main__"
. But if that same filename.py
code is treated as a module (import filename
), then python uses that as the module name instead. In both cases the variable __name__
is set, and testing against that tells you how your code was run.
Just call it and supply self
class A:
def m(self, x, y):
print(x+y)
class B:
def call_a(self):
A.m(self, 1, 2)
b = B()
b.call_a()
output: 3
When you have changes on your working copy, from command line do:
git stash
This will stash your changes and clear your status report
git pull
This will pull changes from upstream branch. Make sure it says fast-forward in the report. If it doesn't, you are probably doing an unintended merge
git stash pop
This will apply stashed changes back to working copy and remove the changes from stash unless you have conflicts. In the case of conflict, they will stay in stash so you can start over if needed.
if you need to see what is in your stash
git stash list
See Android arsenal (category Graphics) for more libraries.
The greater sign ( > ) selector in CSS means that the selector on the right is a direct descendant / child of whatever is on the left.
An example:
article > p { }
Means only style a paragraph that comes after an article.
:vsp
or :sp
- splits vim into two instance but you cannot use :shell in only one of them.
Why not display another tab of the terminal not another tab of vim. If you like the idea you can try it: Ctrl-shift-t.
and move between them with Ctrl - pageup
and Ctrl - pagedown
If you want just a few shell commands you can make any shell command in vim using !
For example :!./a.out
.
In order to stay on the same page on submit you can leave action empty (action=""
) into the form tag, or leave it out altogether.
For the message, create a variable ($message = "Success! You entered: ".$input;"
) and then echo the variable at the place in the page where you want the message to appear with <?php echo $message; ?>
.
Like this:
<?php
$message = "";
if(isset($_POST['SubmitButton'])){ //check if form was submitted
$input = $_POST['inputText']; //get input text
$message = "Success! You entered: ".$input;
}
?>
<html>
<body>
<form action="" method="post">
<?php echo $message; ?>
<input type="text" name="inputText"/>
<input type="submit" name="SubmitButton"/>
</form>
</body>
</html>
nano
does not seem to have the ability to copy/paste from the global/system clipboard or shell.
However, you can copy text from one file to another using nano
's file buffers. When you open another file buffer with ^R
(Ctrl + r), you can use nano
s built-in copy/paste functionality (outlined below) to copy between files:
M-6
(Meta + 6) to copy lines to nano
's clipboard.^K
(Ctrl + k) to cut the current line and store it in nano
's clipboard.^^
(Ctrl + Shift + 6) to select text. Once you have selected the text, you can use the above commands to copy it or cut it.^U
(Ctrl + u) to paste the text from nano
's clipboard.Finally, if the above solution will not work for you and you are using a terminal emulator, you may be able to copy/paste from the global clipboard with Ctrl + Shift + c and Ctrl + Shift + v (Cmd + c and Cmd + v on OSX) respectively. screen
also provides an external copy/paste that should work in nano
. Finally if all you need to do is capture certain lines or text from a file, consider using grep
to find the lines and xclip
or xsel
(or pbcopy
/pbpaste
on OSX) to copy them to the global clipboard (and/or paste from the clipboard) instead of nano
.
$value = ( array_key_exists($key, $array) && !empty($array[$key]) )
? $array[$key]
: 'non-existant or empty value key';
Use .AddRange
to append any Enumrable collection to the list.
This error is pretty verbose:
ValueError: could not convert string to float: id
Somewhere in your text file, a line has the word id
in it, which can't really be converted to a number.
Your test code works because the word id
isn't present in line 2
.
If you want to catch that line, try this code. I cleaned your code up a tad:
#!/usr/bin/python
import os, sys
from scipy import stats
import numpy as np
for index, line in enumerate(open('data2.txt', 'r').readlines()):
w = line.split(' ')
l1 = w[1:8]
l2 = w[8:15]
try:
list1 = map(float, l1)
list2 = map(float, l2)
except ValueError:
print 'Line {i} is corrupt!'.format(i = index)'
break
result = stats.ttest_ind(list1, list2)
print result[1]
This code actually doesn't provide focus:
new Actions(driver).moveToElement(element).perform();
It provides a hover effect.
Additionally, the JS code .focus() requires that the window be active in order to work.
js.executeScript("element.focus();");
I have found that this code works:
element.sendKeys(Keys.SHIFT);
For my own code, I use both:
element.sendKeys(Keys.SHIFT);
js.executeScript("element.focus();");
You cannot determine the encoding of a arbitrary byte stream. This is the nature of encodings. A encoding means a mapping between a byte value and its representation. So every encoding "could" be the right.
The getEncoding() method will return the encoding which was set up (read the JavaDoc) for the stream. It will not guess the encoding for you.
Some streams tell you which encoding was used to create them: XML, HTML. But not an arbitrary byte stream.
Anyway, you could try to guess an encoding on your own if you have to. Every language has a common frequency for every char. In English the char e appears very often but ê will appear very very seldom. In a ISO-8859-1 stream there are usually no 0x00 chars. But a UTF-16 stream has a lot of them.
Or: you could ask the user. I've already seen applications which present you a snippet of the file in different encodings and ask you to select the "correct" one.
As a rule you cannot install other versions of Java on a Mac than those provided by Apple through Software Update. If you need Java 6 you must have a 64-bit Intel computer. You should always have Java 5 and 1.4 and perhaps 1.3 installed if you have at least OS X 10.4.
If you have VERY much elbow grease and is willing to work with beta software you can install the OpenJDK under OS X, but I don't think you want to go there.
I'd call the column "gender".
Data Type Bytes Taken Number/Range of Values
------------------------------------------------
TinyINT 1 255 (zero to 255)
INT 4 - 2,147,483,648 to 2,147,483,647
BIT 1 (2 if 9+ columns) 2 (0 and 1)
CHAR(1) 1 26 if case insensitive, 52 otherwise
The BIT data type can be ruled out because it only supports two possible genders which is inadequate. While INT supports more than two options, it takes 4 bytes -- performance will be better with a smaller/more narrow data type.
CHAR(1)
has the edge over TinyINT - both take the same number of bytes, but CHAR provides a more narrow number of values. Using CHAR(1)
would make using "m", "f",etc natural keys, vs the use of numeric data which are referred to as surrogate/artificial keys. CHAR(1)
is also supported on any database, should there be a need to port.
I would use Option 2: CHAR(1).
An index on the gender column likely would not help because there's no value in an index on a low cardinality column. Meaning, there's not enough variety in the values for the index to provide any value.
Take a look at:
http://java.sun.com/docs/books/tutorial/java/nutsandbolts/operators.html
| is bitwise inclusive OR
|| is logical OR
Microsoft Core Library, ie they are at the heart of everything.
There is a more "massaged" explanation you may prefer:
"When Microsoft first started working on the .NET Framework, MSCorLib.dll was an acronym for Microsoft Common Object Runtime Library. Once ECMA started to standardize the CLR and parts of the FCL, MSCorLib.dll officially became the acronym for Multilanguage Standard Common Object Runtime Library."
From http://weblogs.asp.net/mreynolds/archive/2004/01/31/65551.aspx
Around 1999, to my personal memory, .Net was known as "COOL", so I am a little suspicious of this derivation. I never heard it called "COR", which is a silly-sounding name to a native English speaker.
Giphy Gotcha
After following the 2 requirements listed above (must end in .gif
and using the image syntax), if you are having trouble with a gif from giphy:
Be sure you have the correct giphy url! You can't just add .gif
to the end of this one and have it work.
If you just copy the url from a browser, you will get something like:
https://giphy.com/gifs/gol-automaton-game-of-life-QfsvYoBSSpfbtFJIVo
You need to instead click on "Copy Link" and then grab the "GIF Link" specifically. Notice the correct one points to media.giphy.com
instead of just giphy.com
:
I think the only way of doing this in SQL-Server 2008R2 is to use a correlated subquery, or an outer apply:
SELECT datekey,
COALESCE(RunningTotal, 0) AS RunningTotal,
COALESCE(RunningCount, 0) AS RunningCount,
COALESCE(RunningDistinctCount, 0) AS RunningDistinctCount
FROM document
OUTER APPLY
( SELECT SUM(Amount) AS RunningTotal,
COUNT(1) AS RunningCount,
COUNT(DISTINCT d2.dateKey) AS RunningDistinctCount
FROM Document d2
WHERE d2.DateKey <= document.DateKey
) rt;
This can be done in SQL-Server 2012 using the syntax you have suggested:
SELECT datekey,
SUM(Amount) OVER(ORDER BY DateKey) AS RunningTotal
FROM document
However, use of DISTINCT
is still not allowed, so if DISTINCT is required and/or if upgrading isn't an option then I think OUTER APPLY
is your best option
The windows equivalent to a cron job is a scheduled task.
A scheduled task can be created as described by Alex and Rudu, but it can also be done command line with schtasks
(if you for instance need to script it or add it to version control).
An example:
schtasks /create /tn calculate /tr calc /sc weekly /d MON /st 06:05 /ru "System"
Creates the task calculate, which starts the calculator(calc) every monday at 6:05 (should you ever need that.)
All available commands can be found here: http://technet.microsoft.com/en-us/library/cc772785%28WS.10%29.aspx
It works on windows server 2008 as well as windows server 2003.
Comparison of some of the methods based on the result when the character is not an ASCII digit:
char c1 = (char)('0' - 1), c2 = (char)('9' + 1);
Debug.Print($"{c1 & 15}, {c2 & 15}"); // 15, 10
Debug.Print($"{c1 ^ '0'}, {c2 ^ '0'}"); // 31, 10
Debug.Print($"{c1 - '0'}, {c2 - '0'}"); // -1, 10
Debug.Print($"{(uint)c1 - '0'}, {(uint)c2 - '0'}"); // 4294967295, 10
Debug.Print($"{char.GetNumericValue(c1)}, {char.GetNumericValue(c2)}"); // -1, -1
git diff branch_1..branch_2
That will produce the diff between the tips of the two branches. If you'd prefer to find the diff from their common ancestor to test, you can use three dots instead of two:
git diff branch_1...branch_2
Although this is the accepted answer, toto_tico's answer below is better :)
Try making the onclick js use 'return' to ensure the desired return value gets used...
<button type="button" value="click me" onclick="return check_me();" />
My solution will work if you apply the ActionFilter to the Subcategory action method, as long as you always want to redirect the user to the same bookmark:
http://spikehd.blogspot.com/2012/01/mvc3-redirect-action-to-html-bookmark.html
It modifies the HTML buffer and outputs a small piece of javascript to instruct the browser to append the bookmark.
You could modify the javascript to manually scroll, instead of using a bookmark in the URL, of course!
Hope it helps :)
I tried Ricardo Stuven's way but it didn't work for me. What worked in the end was adding "compact": false to my .babelrc file:
{
"compact": false,
"presets": ["latest", "react", "stage-0"]
}
Buffers are associated with a specific block device, and cover caching of filesystem metadata as well as tracking in-flight pages. The cache only contains parked file data. That is, the buffers remember what's in directories, what file permissions are, and keep track of what memory is being written from or read to for a particular block device. The cache only contains the contents of the files themselves.
If you want to have projects choice list when u open GIT bash:
ppath
in code header to your git projects path, put this code into .bashrc file and copy it into your $HOME dir (in Win Vista / 7 it is usually c:\Users\$YOU)#!/bin/bash
ppath="/d/-projects/-github"
cd $ppath
unset PROJECTS
PROJECTS+=(".")
i=0
echo
echo -e "projects:\n-------------"
for f in *
do
if [ -d "$f" ]
then
PROJECTS+=("$f")
echo -e $((++i)) "- \e[1m$f\e[0m"
fi
done
if [ ${#PROJECTS[@]} -gt 1 ]
then
echo -ne "\nchoose project: "
read proj
case "$proj" in
[0-`expr ${#PROJECTS[@]} - 1`]) cd "${PROJECTS[proj]}" ;;
*) echo " wrong choice" ;;
esac
else
echo "there is no projects"
fi
unset PROJECTS
With Java 7's try-with-resources Jiri's answer can be improved upon:
try (BufferedReader br = new BufferedReader(new FileReader("foo.txt"))) {
String line = null;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
}
Add exception handling at the place of your choice, either in this try
or elsewhere.
make global function
func convertDateFormat(inputDate: String) -> String {
let olDateFormatter = DateFormatter()
olDateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
let oldDate = olDateFormatter.date(from: inputDate)
let convertDateFormatter = DateFormatter()
convertDateFormatter.dateFormat = "MMM dd yyyy h:mm a"
return convertDateFormatter.string(from: oldDate!)
}
Called function and pass value in it
get_OutputStr = convertDateFormat(inputDate: "2019-03-30T05:30:00+0000")
and here is output
Feb 25 2020 4:51 PM
As other answers have said, the best way to do this involves making a new list - either iterate over a copy, or construct a list with only the elements you want and assign it back to the same variable. The difference between these depends on your use case, since they affect other variables for the original list differently (or, rather, the first affects them, the second doesn't).
If a copy isn't an option for some reason, you do have one other option that relies on an understanding of why modifying a list you're iterating breaks. List iteration works by keeping track of an index, incrementing it each time around the loop until it falls off the end of the list. So, if you remove at (or before) the current index, everything from that point until the end shifts one spot to the left. But the iterator doesn't know about this, and effectively skips the next element since it is now at the current index rather than the next one. However, removing things that are after the current index doesn't affect things.
This implies that if you iterate the list back to front, if you remove an item at the current index, everything to it's right shifts left - but that doesn't matter, since you've already dealt with all the elements to the right of the current position, and you're moving left - the next element to the left is unaffected by the change, and so the iterator gives you the element you expect.
TL;DR:
>>> a = list(range(5))
>>> for b in reversed(a):
if b == 3:
a.remove(b)
>>> a
[0, 1, 2, 4]
However, making a copy is usually better in terms of making your code easy to read. I only mention this possibility for sake of completeness.
System.Windows.Forms.Application.StartupPath
will solve your problem, I think
With your own Code and a Slight Change withou jQuery,
function testingAPI(){
var key = "8a1c6a354c884c658ff29a8636fd7c18";
var url = "https://api.fantasydata.net/nfl/v2/JSON/PlayerSeasonStats/2015";
console.log(httpGet(url,key));
}
function httpGet(url,key){
var xmlHttp = new XMLHttpRequest();
xmlHttp.open( "GET", url, false );
xmlHttp.setRequestHeader("Ocp-Apim-Subscription-Key",key);
xmlHttp.send(null);
return xmlHttp.responseText;
}
Thank You
I always prefer let
to an instance variable for a couple of reasons:
nil
, which can lead to subtle bugs and false positives. Since let
creates a method, you'll get a NameError
when you misspell it, which I find preferable. It makes it easier to refactor specs, too.before(:each)
hook will run before each example, even if the example doesn't use any of the instance variables defined in the hook. This isn't usually a big deal, but if the setup of the instance variable takes a long time, then you're wasting cycles. For the method defined by let
, the initialization code only runs if the example calls it.@
).let
and keeping my it
block nice and short.A related link can be found here: http://www.betterspecs.org/#let
You can use the query
function, so if your data were in col A where the first row was the column title...
=query(A2:A,"select A, count(A) where A != '' group by A order by count(A) desc label A 'City'", 0)
yields
City count
London 2
Paris 2
Berlin 1
Rome 1
Link to working Google Sheet.
https://docs.google.com/spreadsheets/d/1N5xw8-YP2GEPYOaRkX8iRA6DoeRXI86OkfuYxwXUCbc/edit#gid=0
In case you don't know it already, Oracle has released ODP.NET which supports Entity Framework. It doesn't support code first yet though.
http://www.oracle.com/technetwork/topics/dotnet/index-085163.html
Use
=LEFT(B2, 2)*3600000 + MID(B2,4,2) * 60000 + MID(B2,7,2)*1000 + RIGHT(B2,3)
Just for reference, a for
loop can be used after getting the first row to get the rest of the file:
with open('file.csv', newline='') as f:
reader = csv.reader(f)
row1 = next(reader) # gets the first line
for row in reader:
print(row) # prints rows 2 and onward
There is no specific event for capturing browser close event. But we can detect by the browser positions XY.
<script type="text/javascript">
$(document).ready(function() {
$(document).mousemove(function(e) {
if(e.pageY <= 5)
{
//this condition would occur when the user brings their cursor on address bar
//do something here
}
});
});
</script>
Let me try a complex computation using datetime and considering nulls or empty spaces. I am reducing 30 years on a datetime column and using apply
method as well as lambda
and converting datetime format. Line if x != '' else x
will take care of all empty spaces or nulls accordingly.
df['Date'] = df['Date'].fillna('')
df['Date'] = df['Date'].apply(lambda x : ((datetime.datetime.strptime(str(x), '%m/%d/%Y') - datetime.timedelta(days=30*365)).strftime('%Y%m%d')) if x != '' else x)
A other users suggested,
.empty()
is good enought, because it removes all descendant nodes (both tag-nodes and text-nodes) AND all kind of data stored inside those nodes. See the JQuery's API empty documentation.
If you wish to keep data, like event handlers for example, you should use
.detach()
as described on the JQuery's API detach documentation.
The method .remove() could be usefull for similar purposes.
Create a Pivot Table. It has these features and many more.
If you are dead-set on doing this yourself then you could add shapes to the worksheet and use VBA to hide and unhide rows and columns on clicking the shapes.
Simply .Contains() would do the work for you.
"Example String".Contains("amp"); //like '%amp%'
This would return true, and performing a select on it would return the desired output.
Format with Currency format string
=Format(Fields!Price.Value, "C")
It will give you 2 decimal places with "$" prefixed.
You can find other format strings on MSDN: Adding Style and Formatting to a ReportViewer Report
Note: The MSDN article has been archived to the "VS2005_General" document, which is no longer directly accessible online. Here is the excerpt of the formatting strings referenced:
Formatting Numbers
The following table lists common .NET Framework number formatting strings.
Format string, Name
C or c Currency
D or d Decimal
E or e Scientific
F or f Fixed-point
G or g General
N or n Number
P or p Percentage
R or r Round-trip
X or x Hexadecimal
You can modify many of the format strings to include a precision specifier that defines the number of digits to the right of the
decimal point. For example, a formatting string of D0 formats the number so that it has no digits after the decimal point. You
can also use custom formatting strings, for example, #,###.
Formatting Dates
The following table lists common .NET Framework date formatting strings.
Format string, Name
d Short date
D Long date
t Short time
T Long time
f Full date/time (short time)
F Full date/time (long time)
g General date/time (short time)
G General date/time (long time)
M or m Month day
R or r RFC1123 pattern
Y or y Year month
You can also a use custom formatting strings; for example, dd/MM/yy. For more information about .NET Framework formatting strings, see Formatting Types.
Your implementation (the one in the question) is faster than e.g. wrapping with toList()
and using a comparator-based method. Auto-boxing and running through comparator methods or wrapped Collections objects is far slower than just reversing.
Of course you could write your own sort. That might not be the answer you're looking for, but note that if your comment about "if the array is already sorted quite well" happens frequently, you might do well to choose a sorting algorithm that handles that case well (e.g. insertion) rather than use Arrays.sort()
(which is mergesort, or insertion if the number of elements is small).
"How to find all a
which are children of <li class=test>
but not any others?"
Given the HTML below (I added another <a>
to show te difference between select
and select_one
):
<div>
<li class="test">
<a>link1</a>
<ul>
<li>
<a>link2</a>
</li>
</ul>
<a>link3</a>
</li>
</div>
The solution is to use child combinator (>
) that is placed between two CSS selectors:
>>> soup.select('li.test > a')
[<a>link1</a>, <a>link3</a>]
In case you want to find only the first child:
>>> soup.select_one('li.test > a')
<a>link1</a>
Here is @DwB solution upgraded to Commons CLI 1.3.1 compliance (replaced deprecated components OptionBuilder and GnuParser). The Apache documentation uses examples that in real life have unmarked/bare arguments but ignores them. Thanks @DwB for showing how it works.
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.DefaultParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
public static void main(String[] parameters) {
CommandLine commandLine;
Option option_A = Option.builder("A").argName("opt3").hasArg().desc("The A option").build();
Option option_r = Option.builder("r").argName("opt1").hasArg().desc("The r option").build();
Option option_S = Option.builder("S").argName("opt2").hasArg().desc("The S option").build();
Option option_test = Option.builder().longOpt("test").desc("The test option").build();
Options options = new Options();
CommandLineParser parser = new DefaultParser();
options.addOption(option_A);
options.addOption(option_r);
options.addOption(option_S);
options.addOption(option_test);
String header = " [<arg1> [<arg2> [<arg3> ...\n Options, flags and arguments may be in any order";
String footer = "This is DwB's solution brought to Commons CLI 1.3.1 compliance (deprecated methods replaced)";
HelpFormatter formatter = new HelpFormatter();
formatter.printHelp("CLIsample", header, options, footer, true);
String[] testArgs =
{ "-r", "opt1", "-S", "opt2", "arg1", "arg2",
"arg3", "arg4", "--test", "-A", "opt3", };
try
{
commandLine = parser.parse(options, testArgs);
if (commandLine.hasOption("A"))
{
System.out.print("Option A is present. The value is: ");
System.out.println(commandLine.getOptionValue("A"));
}
if (commandLine.hasOption("r"))
{
System.out.print("Option r is present. The value is: ");
System.out.println(commandLine.getOptionValue("r"));
}
if (commandLine.hasOption("S"))
{
System.out.print("Option S is present. The value is: ");
System.out.println(commandLine.getOptionValue("S"));
}
if (commandLine.hasOption("test"))
{
System.out.println("Option test is present. This is a flag option.");
}
{
String[] remainder = commandLine.getArgs();
System.out.print("Remaining arguments: ");
for (String argument : remainder)
{
System.out.print(argument);
System.out.print(" ");
}
System.out.println();
}
}
catch (ParseException exception)
{
System.out.print("Parse error: ");
System.out.println(exception.getMessage());
}
}
Output:
usage: CLIsample [-A <opt3>] [-r <opt1>] [-S <opt2>] [--test]
[<arg1> [<arg2> [<arg3> ...
Options, flags and arguments may be in any order
-A <opt3> The A option
-r <opt1> The r option
-S <opt2> The S option
--test The test option
This is DwB's solution brought to Commons CLI 1.3.1 compliance (deprecated
methods replaced)
Option A is present. The value is: opt3
Option r is present. The value is: opt1
Option S is present. The value is: opt2
Option test is present. This is a flag option.
Remaining arguments: arg1 arg2 arg3 arg4
Solved it with 2 steps.
- Update 2 parameters in the config file application/config/config.php
$config['index_page'] = '';
$config['uri_protocol'] = 'REQUEST_URI';
- Update the file .htaccess in the root folder
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?/$1 [L]
</IfModule>
In My Case, Im trying to pass messages from Salesforce Marketing Cloud Custom Activity(Domain 1) to Heroku(Domain 2) on load.
The Error Appeared in console, when I loaded my original html page from where message is being passed.
Issue I noticed after reading many blogs is that, the receiver page is not loaded yet. i.e
I need to debug from my receiver page not from sender page.
Simple but glad if it helps anyone.
@chapinkapa's answer is good. An approach that I have taken since Mobile Center does not support environment variables, is to expose build configuration through a native module:
On android:
@Override
public Map<String, Object> getConstants() {
final Map<String, Object> constants = new HashMap<>();
String buildConfig = BuildConfig.BUILD_TYPE.toLowerCase();
constants.put("ENVIRONMENT", buildConfig);
return constants;
}
or on ios:
override func constantsToExport() -> [String: Any]! {
// debug/ staging / release
// on android, I can tell the build config used, but here I use bundle name
let STAGING = "staging"
let DEBUG = "debug"
var environment = "release"
if let bundleIdentifier: String = Bundle.main.bundleIdentifier {
if (bundleIdentifier.lowercased().hasSuffix(STAGING)) {
environment = STAGING
} else if (bundleIdentifier.lowercased().hasSuffix(DEBUG)){
environment = DEBUG
}
}
return ["ENVIRONMENT": environment]
}
You can read the build config synchronously and decide in Javascript how you're going to behave.
You need to do something like this:
// instantiate XmlDocument and load XML from file
XmlDocument doc = new XmlDocument();
doc.Load(@"D:\test.xml");
// get a list of nodes - in this case, I'm selecting all <AID> nodes under
// the <GroupAIDs> node - change to suit your needs
XmlNodeList aNodes = doc.SelectNodes("/Equipment/DataCollections/GroupAIDs/AID");
// loop through all AID nodes
foreach (XmlNode aNode in aNodes)
{
// grab the "id" attribute
XmlAttribute idAttribute = aNode.Attributes["id"];
// check if that attribute even exists...
if (idAttribute != null)
{
// if yes - read its current value
string currentValue = idAttribute.Value;
// here, you can now decide what to do - for demo purposes,
// I just set the ID value to a fixed value if it was empty before
if (string.IsNullOrEmpty(currentValue))
{
idAttribute.Value = "515";
}
}
}
// save the XmlDocument back to disk
doc.Save(@"D:\test2.xml");
@last_run_time
is a 9.4. User-Defined Variables and last_run_time datetime
one 13.6.4.1. Local Variable DECLARE Syntax, are different variables.
Try: SELECT last_run_time;
UPDATE
Example:
/* CODE FOR DEMONSTRATION PURPOSES */
DELIMITER $$
CREATE PROCEDURE `sp_test`()
BEGIN
DECLARE current_procedure_name CHAR(60) DEFAULT 'accounts_general';
DECLARE last_run_time DATETIME DEFAULT NULL;
DECLARE current_run_time DATETIME DEFAULT NOW();
-- Define the last run time
SET last_run_time := (SELECT MAX(runtime) FROM dynamo.runtimes WHERE procedure_name = current_procedure_name);
-- if there is no last run time found then use yesterday as starting point
IF(last_run_time IS NULL) THEN
SET last_run_time := DATE_SUB(NOW(), INTERVAL 1 DAY);
END IF;
SELECT last_run_time;
-- Insert variables in table2
INSERT INTO table2 (col0, col1, col2) VALUES (current_procedure_name, last_run_time, current_run_time);
END$$
DELIMITER ;
The windows.load function is useful if you want to do something when everything is loaded.
$(window).load(function(){
// full load
});
But you can also use the .load function on any other element. So if you have one particularly large image and you want to do something when that loads but the rest of your page loading code when the dom has loaded you could do:
$(function(){
// Dom loaded code
$('#largeImage').load({
// Image loaded code
});
});
Also the jquery .load function is pretty much the same as a normal .onload.
I put together a little C program to print out the current timestamp (locale-safe, no bad characters...). Then, I use the FOR command to save the result in an environment variable:
:: Get the timestamp
for /f %%x in ('@timestamp') do set TIMESTAMP=%%x
:: Use it to generate a filename
for /r %%x in (.\processed\*) do move "%%~x" ".\archived\%%~nx-%TIMESTAMP%%%~xx"
Here's a link:
In case anyone having problem with Samsung GT-I9060 I followed this answer on SO:
If you are on windows, many times it will not recognize the device fully and because of driver issues, the device won't show up.
- go to settings
- control panel
- hardware and sound
- device manager
And look for any devices showing an error. Many androids will show as an unknown USB device. Select that device and try to update the drivers for it.
I uninstalled the device, unplug the device and plug it again. This time Windows properly installed the driver. What a bummer.
del is the equivalent of "unset" in many languages and as a cross reference point moving from another language to python.. people tend to look for commands that do the same thing that they used to do in their first language... also setting a var to "" or none doesn't really remove the var from scope..it just empties its value the name of the var itself would still be stored in memory...why?!? in a memory intensive script..keeping trash behind its just a no no and anyways...every language out there has some form of an "unset/delete" var function..why not python?
This works just as well: http://jsfiddle.net/maniator/ge59E/3/
var reg = new RegExp(" ","g"); //<< just look for a space.
Unfortunately for MSForms list box looping through the list items and checking their Selected property is the only way. However, here is an alternative. I am storing/removing the selected item in a variable, you can do this in some remote cell and keep track of it :)
Dim StrSelection As String
Private Sub ListBox1_Change()
If ListBox1.Selected(ListBox1.ListIndex) Then
If StrSelection = "" Then
StrSelection = ListBox1.List(ListBox1.ListIndex)
Else
StrSelection = StrSelection & "," & ListBox1.List(ListBox1.ListIndex)
End If
Else
StrSelection = Replace(StrSelection, "," & ListBox1.List(ListBox1.ListIndex), "")
End If
End Sub
You don't need:
@Configuration
@ComponentScan("com.company.praktikant")
@EnableWebSecurity
already has @Configuration
in it, and I cannot imagine why you put @ComponentScan
there.
About CORS filter, I would just put this:
@Bean
public FilterRegistrationBean corsFilter() {
UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
CorsConfiguration config = new CorsConfiguration();
config.setAllowCredentials(true);
config.addAllowedOrigin("*");
config.addAllowedHeader("*");
config.addAllowedMethod("*");
source.registerCorsConfiguration("/**", config);
FilterRegistrationBean bean = new FilterRegistrationBean(new CorsFilter(source));
bean.setOrder(0);
return bean;
}
Into SecurityConfiguration class and remove configure and configure global methods. You don't need to set allowde orgins, headers and methods twice. Especially if you put different properties in filter and spring security config :)
According to above, your "MyFilter" class is redundant.
You can also remove those:
final AnnotationConfigApplicationContext annotationConfigApplicationContext = new AnnotationConfigApplicationContext();
annotationConfigApplicationContext.register(CORSConfig.class);
annotationConfigApplicationContext.refresh();
From Application class.
At the end small advice - not connected to the question. You don't want to put verbs in URI. Instead of http://localhost:8080/getKunden
you should use HTTP GET method on http://localhost:8080/kunden
resource. You can learn about best practices for design RESTful api here: http://www.vinaysahni.com/best-practices-for-a-pragmatic-restful-api
Simplest one is: Install "ShareIt" app on phone. Now install shareIt app in PC or other phone. Now from the phone, where the app is installed, open ShareIt and send. On other phone or PC, open ShareIt and receive.
In my case, I had created the map, but was missing the ReverseMap function. Adding it got rid of the error.
private static void RegisterServices(ContainerBuilder bldr)
{
var config = new MapperConfiguration(cfg =>
{
cfg.AddProfile(new CampMappingProfile());
});
...
}
public CampMappingProfile()
{
CreateMap<Talk, TalkModel>().ReverseMap();
...
}
Below is a working code to add a fragment e.g 3 times to a vertical LinearLayout (xNumberLinear). You can change number 3 with any other number or take a number from a spinner!
for (int i = 0; i < 3; i++) {
LinearLayout linearDummy = new LinearLayout(getActivity());
linearDummy.setOrientation(LinearLayout.VERTICAL);
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN_MR1) {
Toast.makeText(getActivity(), "This function works on newer versions of android", Toast.LENGTH_LONG).show();
} else {
linearDummy.setId(View.generateViewId());
}
fragmentManager.beginTransaction().add(linearDummy.getId(), new SomeFragment(),"someTag1").commit();
xNumberLinear.addView(linearDummy);
}
I had the same problem when my network config was incorrect and DNS was not resolving. In other words the issue could arise when there is no Network Access.
If anyone faces the following error message when they use adb devices
no permissions (verify udev rules); see [http://developer.android.com/tools/device.html]
Execute the following
sudo -s
adb kill-server
adb start-server
That fixed the issue for me on a custom build android device
FYI - if you are importing a List into a JSP, chances are pretty good that you are violating MVC principles. Take a few hours now to read up on the MVC approach to web app development (including use of taglibs) - do some more googling on the subject, it's fascinating and will definitely help you write better apps.
If you are doing anything more complicated than a single JSP displaying some database results, please consider using a framework like Spring, Grails, etc... It will absolutely take you a bit more effort to get going, but it will save you so much time and effort down the road that I really recommend it. Besides, it's cool stuff :-)
Even another possibility: using blocks in queues, it might easily happen that you try to access an object in another queue, that has already been de-allocated at this time. Typically when you try to send something to the GUI. If your exception breakpoint is being set at a strange place, then this might be the cause.
for color in ['r', 'b', 'g', 'k', 'm']:
plot(x, y, color=color)
In my case I'd forgotten the open and close parantheses at the end of the definition of the function wrapping all of my code in the exported module. I.e. I had:
(function () {
'use strict';
module.exports.MyClass = class{
...
);
Instead of:
(function () {
'use strict';
module.exports.MyClass = class{
...
)();
The compiler doesn't complain, but the require statement in the importing module doesn't set the variable it's being assigned to, so it's undefined at the point you try to construct it and it will give the TypeError: MyClass is not a constructor
error.
This will tell you what line is the problem.
import csv
lines = []
with open('output.txt','r') as f:
for line in f.readlines():
lines.append(line[:-1])
with open('corrected.csv','w') as correct:
writer = csv.writer(correct, dialect = 'excel')
with open('input.csv', 'r') as mycsv:
reader = csv.reader(mycsv)
try:
for i, row in enumerate(reader):
if row[0] not in lines:
writer.writerow(row)
except csv.Error:
print('csv choked on line %s' % (i+1))
raise
Perhaps this from daniweb would be helpful:
I'm getting this error when reading from a csv file: "Runtime Error! line contains NULL byte". Any idea about the root cause of this error?
...
Ok, I got it and thought I'd post the solution. Simply yet caused me grief... Used file was saved in a .xls format instead of a .csv Didn't catch this because the file name itself had the .csv extension while the type was still .xls
To install android studio on ubuntu here is the simplest way possible:
First of all, you have to install Ubuntu Make before installing Android Studio. Type following commands in the same order one by one on terminal:
1) sudo add-apt-repository ppa:ubuntu-desktop/ubuntu-make
2) sudo apt-get update
3) sudo apt-get install ubuntu-make
Now since you are done with Ubuntu make, use below command to install Android Studio:
4) umake android
While installation it will give you a couple of option which you can handle. So, Installation is done. You can open it and run an App of your choice. Isn’t it very easy? Let me know if you go through any problem, I can help.
Source Install Android Studio
Depending on the length of the wanted loop, maybe even a more "template-driven" solution:
<ul>
<li *ngFor="let index of [0,1,2,3,4,5]">
{{ index }}
</li>
</ul>
what is the way to retrieve a Date object so that its always in GMT?
Instant.now()
You are using troublesome confusing old date-time classes that are now supplanted by the java.time classes.
Instant
= UTCThe Instant
class represents a moment on the timeline in UTC with a resolution of nanoseconds (up to nine (9) digits of a decimal fraction).
Instant instant = Instant.now() ; // Current moment in UTC.
To exchange this data as text, use the standard ISO 8601 formats exclusively. These formats are sensibly designed to be unambiguous, easy to process by machine, and easy to read across many cultures by people.
The java.time classes use the standard formats by default when parsing and generating strings.
String output = instant.toString() ;
2017-01-23T12:34:56.123456789Z
If you want to see that same moment as presented in the wall-clock time of a particular region, apply a ZoneId
to get a ZonedDateTime
.
Specify a proper time zone name in the format of continent/region
, such as America/Montreal
, Africa/Casablanca
, or Pacific/Auckland
. Never use the 3-4 letter abbreviation such as EST
or IST
as they are not true time zones, not standardized, and not even unique(!).
ZoneId z = ZoneId.of( "Asia/Singapore" ) ;
ZonedDateTime zdt = instant.atZone( z ) ; // Same simultaneous moment, same point on the timeline.
See this code live at IdeOne.com.
Notice the eight hour difference, as the time zone of Asia/Singapore
currently has an offset-from-UTC of +08:00. Same moment, different wall-clock time.
instant.toString(): 2017-01-23T12:34:56.123456789Z
zdt.toString(): 2017-01-23T20:34:56.123456789+08:00[Asia/Singapore]
Avoid the legacy java.util.Date
class. But if you must, you can convert. Look to new methods added to the old classes.
java.util.Date date = Date.from( instant ) ;
…going the other way…
Instant instant = myJavaUtilDate.toInstant() ;
For date-only, use LocalDate
.
LocalDate ld = zdt.toLocalDate() ;
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date
, Calendar
, & SimpleDateFormat
.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
Where to obtain the java.time classes?
The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval
, YearWeek
, YearQuarter
, and more.
On the one hand, when you call System.getProperty("java.io.tmpdir")
instruction, Java calls the Win32 API's function GetTempPath
.
According to the MSDN :
The GetTempPath function checks for the existence of environment variables in the following order and uses the first path found:
- The path specified by the TMP environment variable.
- The path specified by the TEMP environment variable.
- The path specified by the USERPROFILE environment variable.
- The Windows directory.
On the other hand, please check the historical reasons on why TMP
and TEMP
coexist. It's really worth reading.
I was trying to use Feign, while I encounter same issue, As I understood HTTP message converter will help but wanted to understand how to achieve this.
@FeignClient(name = "mobilesearch", url = "${mobile.search.uri}" ,
fallbackFactory = MobileSearchFallbackFactory.class,
configuration = MobileSearchFeignConfig.class)
public interface MobileSearchClient {
@RequestMapping(method = RequestMethod.GET)
List<MobileSearchResponse> getPhones();
}
You have to use Customer Configuration for the decoder, MobileSearchFeignConfig,
public class MobileSearchFeignConfig {
@Bean
Logger.Level feignLoggerLevel() {
return Logger.Level.FULL;
}
@Bean
public Decoder feignDecoder() {
return new ResponseEntityDecoder(new SpringDecoder(feignHttpMessageConverter()));
}
public ObjectFactory<HttpMessageConverters> feignHttpMessageConverter() {
final HttpMessageConverters httpMessageConverters = new HttpMessageConverters(new MappingJackson2HttpMessageConverter());
return new ObjectFactory<HttpMessageConverters>() {
@Override
public HttpMessageConverters getObject() throws BeansException {
return httpMessageConverters;
}
};
}
public class MappingJackson2HttpMessageConverter extends org.springframework.http.converter.json.MappingJackson2HttpMessageConverter {
MappingJackson2HttpMessageConverter() {
List<MediaType> mediaTypes = new ArrayList<>();
mediaTypes.add(MediaType.valueOf(MediaType.TEXT_HTML_VALUE + ";charset=UTF-8"));
setSupportedMediaTypes(mediaTypes);
}
}
}
Just so others who have configured their apps like mine benefit from what I went through...
None of the above solutions worked for me because I have a ./config
directory just under my project base with 2 files:
application.properties
application-dev.properties
In application.properties
I have:
spring.profiles.active = dev # set my default profile to 'dev'
In application-dev.properties
I have:
server_host = localhost
server_port = 8080
This is so when I run my fat jar from the CLI the *.properties
files will be read from the ./config
dir and all is good.
Well, it turns out that these properties files completely override the webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT
setting in @SpringBootTest
in my Spock specs. No matter what I tried, even with webEnvironment
set to RANDOM_PORT
Spring would always startup the embedded Tomcat container on port 8080 (or whatever value I'd set in my ./config/*.properties
files).
The ONLY way I was able to overcome this was by adding an explicit properties = "server_port=0"
to the @SpringBootTest
annotation in my Spock integration specs:
@SpringBootTest (webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT, properties = "server_port=0")
Then, and only then did Spring finally start to spin up Tomcat on a random port. IMHO this is a Spring testing framework bug, but I'm sure they'll have their own opinion on this.
Hope this helped someone.
In case you decide to use dangerous code that is subject to breakage, this extension function will fetch a key from a Dictionary<K,V>
according to its internal indexing (which for Mono and .NET currently appears to be in the same order as you get by enumerating the Keys
property).
It is much preferable to use Linq: dict.Keys.ElementAt(i)
, but that function will iterate O(N); the following is O(1) but with a reflection performance penalty.
using System;
using System.Collections.Generic;
using System.Reflection;
public static class Extensions
{
public static TKey KeyByIndex<TKey,TValue>(this Dictionary<TKey, TValue> dict, int idx)
{
Type type = typeof(Dictionary<TKey, TValue>);
FieldInfo info = type.GetField("entries", BindingFlags.NonPublic | BindingFlags.Instance);
if (info != null)
{
// .NET
Object element = ((Array)info.GetValue(dict)).GetValue(idx);
return (TKey)element.GetType().GetField("key", BindingFlags.Public | BindingFlags.Instance).GetValue(element);
}
// Mono:
info = type.GetField("keySlots", BindingFlags.NonPublic | BindingFlags.Instance);
return (TKey)((Array)info.GetValue(dict)).GetValue(idx);
}
};
You can pass the necessary variables from the parent scope into the closure with the use
keyword.
For example:
DB::table('users')->where(function ($query) use ($activated) {
$query->where('activated', '=', $activated);
})->get();
More on that here.
PHP 7.4 (will be released at November 28, 2019) introduces a shorter variation of the anonymous functions called arrow functions which makes this a bit less verbose.
An example using PHP 7.4 which is functionally nearly equivalent (see the 3rd bullet point below):
DB::table('users')->where(fn($query) => $query->where('activated', '=', $activated))->get();
Differences compared to the regular syntax:
fn
keyword instead of function
.use
keyword in the latter example.void
return type when declaring them.return
keyword must be omitted.i didn't find who made elegant answer , that's why let me say :
Array.from(
document.querySelectorAll('#txt1,#txt2')
).map(e => parseInt(e.value) || 0) // to avoid NaN
.reduce((a, b) => a+b, 0)
window.sum= () => _x000D_
document.getElementById('result').innerHTML= _x000D_
Array.from(_x000D_
document.querySelectorAll('#txt1,#txt2')_x000D_
).map(e=>parseInt(e.value)||0)_x000D_
.reduce((a,b)=>a+b,0)
_x000D_
<input type="text" id="txt1" onkeyup="sum()"/>_x000D_
<input type="text" id="txt2" onkeyup="sum()" style="margin-right:10px;"/><span id="result"></span>
_x000D_