Border color on default input style
You can use jquery for this by utilizing addClass() method
CSS
.defaultInput
{
width: 100px;
height:25px;
padding: 5px;
}
.error
{
border:1px solid red;
}
<input type="text" class="defaultInput"/>
Jquery Code
$(document).ready({
$('.defaultInput').focus(function(){
$(this).addClass('error');
});
});
Update: You can remove that error class using
$('.defaultInput').removeClass('error');
It won't remove that default style. It will remove .error class only
How to store(bitmap image) and retrieve image from sqlite database in android?
If you are working with Android's MediaStore database, here is how to store an image and then display it after it is saved.
on button click write this
Intent in = new Intent(Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
in.putExtra("crop", "true");
in.putExtra("outputX", 100);
in.putExtra("outputY", 100);
in.putExtra("scale", true);
in.putExtra("return-data", true);
startActivityForResult(in, 1);
then do this in your activity
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1 && resultCode == RESULT_OK && data != null) {
Bitmap bmp = (Bitmap) data.getExtras().get("data");
img.setImageBitmap(bmp);
btnadd.requestFocus();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.JPEG, 100, baos);
byte[] b = baos.toByteArray();
String encodedImageString = Base64.encodeToString(b, Base64.DEFAULT);
byte[] bytarray = Base64.decode(encodedImageString, Base64.DEFAULT);
Bitmap bmimage = BitmapFactory.decodeByteArray(bytarray, 0,
bytarray.length);
}
}
How can I read numeric strings in Excel cells as string (not numbers)?
I would recommend the following approach when modifying cell's type is undesirable:
if(cell.getCellType() == Cell.CELL_TYPE_NUMERIC) {
String str = NumberToTextConverter.toText(cell.getNumericCellValue())
}
NumberToTextConverter can correctly convert double value to a text using Excel's rules without precision loss.
What is the difference between Cloud, Grid and Cluster?
Cluster differs from Cloud and Grid in that a cluster is a group of computers connected by a local area network (LAN), whereas cloud and grid are more wide scale and can be geographically distributed. Another way to put it is to say that a cluster is tightly coupled, whereas a Grid or a cloud is loosely coupled. Also, clusters are made up of machines with similar hardware, whereas clouds and grids are made up of machines with possibly very different hardware configurations.
To know more about cloud computing, I recommend reading this paper: «Above the Clouds: A Berkeley View of Cloud Computing», Michael Armbrust, Armando Fox, Rean Griffith, Anthony D. Joseph, Randy H. Katz, Andrew Konwinski, Gunho Lee, David A. Patterson, Ariel Rabkin, Ion Stoica and Matei Zaharia. The following is an abstract from the above paper:
Cloud Computing refers to both the applications delivered as services over the Internet and the hardware and systems software in the datacenters that provide those services. The services themselves have long been referred to as Software as a Service (SaaS). The datacenter hardware and software is what we call a Cloud. When a Cloud is made available in a pay-as-you-go manner to the general public, we call it a Public Cloud; the service being sold is Utility Computing. We use the term Private Cloud to refer to internal datacenters of a business or other organization, not made available to the general public. Thus, Cloud Computing is the sum of SaaS and Utility Computing, but does not include Private Clouds. People can be users or providers of SaaS, or users or providers of Utility Computing.
The difference between a cloud and a grid can be expressed as below:
Resource distribution: Cloud computing is a centralized model whereas grid computing is a decentralized model where the computation could occur over many administrative domains.
Ownership: A grid is a collection of computers which is owned by multiple parties in multiple locations and connected together so that users can share the combined power of resources. Whereas a cloud is a collection of computers usually owned by a single party.
Examples of Clouds: Amazon Web Services (AWS), Google App Engine.
Examples of Grids: FutureGrid.
Examples of cloud computing services: Dropbox, Gmail, Facebook, Youtube, RapidShare.
How do I access my SSH public key?
If you're using windows, the command is:
type %userprofile%\.ssh\id_rsa.pubit should print the key (if you have one). You should copy the entire result. If none is present, then do:
ssh-keygen -t rsa -C "[email protected]" -b 4096Dynamically adding properties to an ExpandoObject
dynamic x = new ExpandoObject();
x.NewProp = string.Empty;
Alternatively:
var x = new ExpandoObject() as IDictionary<string, Object>;
x.Add("NewProp", string.Empty);
Where can I get a list of Ansible pre-defined variables?
Argh! From the FAQ:
How do I see a list of all of the ansible_ variables? Ansible by default gathers “facts” about the machines under management, and these facts can be accessed in Playbooks and in templates. To see a list of all of the facts that are available about a machine, you can run the “setup” module as an ad-hoc action:
ansible -m setup hostname
This will print out a dictionary of all of the facts that are available for that particular host.
Here is the output for my vagrant virtual machine called scdev:
scdev | success >> {
"ansible_facts": {
"ansible_all_ipv4_addresses": [
"10.0.2.15",
"192.168.10.10"
],
"ansible_all_ipv6_addresses": [
"fe80::a00:27ff:fe12:9698",
"fe80::a00:27ff:fe74:1330"
],
"ansible_architecture": "i386",
"ansible_bios_date": "12/01/2006",
"ansible_bios_version": "VirtualBox",
"ansible_cmdline": {
"BOOT_IMAGE": "/vmlinuz-3.2.0-23-generic-pae",
"quiet": true,
"ro": true,
"root": "/dev/mapper/precise32-root"
},
"ansible_date_time": {
"date": "2013-09-17",
"day": "17",
"epoch": "1379378304",
"hour": "00",
"iso8601": "2013-09-17T00:38:24Z",
"iso8601_micro": "2013-09-17T00:38:24.425092Z",
"minute": "38",
"month": "09",
"second": "24",
"time": "00:38:24",
"tz": "UTC",
"year": "2013"
},
"ansible_default_ipv4": {
"address": "10.0.2.15",
"alias": "eth0",
"gateway": "10.0.2.2",
"interface": "eth0",
"macaddress": "08:00:27:12:96:98",
"mtu": 1500,
"netmask": "255.255.255.0",
"network": "10.0.2.0",
"type": "ether"
},
"ansible_default_ipv6": {},
"ansible_devices": {
"sda": {
"holders": [],
"host": "SATA controller: Intel Corporation 82801HM/HEM (ICH8M/ICH8M-E) SATA Controller [AHCI mode] (rev 02)",
"model": "VBOX HARDDISK",
"partitions": {
"sda1": {
"sectors": "497664",
"sectorsize": 512,
"size": "243.00 MB",
"start": "2048"
},
"sda2": {
"sectors": "2",
"sectorsize": 512,
"size": "1.00 KB",
"start": "501758"
},
},
"removable": "0",
"rotational": "1",
"scheduler_mode": "cfq",
"sectors": "167772160",
"sectorsize": "512",
"size": "80.00 GB",
"support_discard": "0",
"vendor": "ATA"
},
"sr0": {
"holders": [],
"host": "IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)",
"model": "CD-ROM",
"partitions": {},
"removable": "1",
"rotational": "1",
"scheduler_mode": "cfq",
"sectors": "2097151",
"sectorsize": "512",
"size": "1024.00 MB",
"support_discard": "0",
"vendor": "VBOX"
},
"sr1": {
"holders": [],
"host": "IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)",
"model": "CD-ROM",
"partitions": {},
"removable": "1",
"rotational": "1",
"scheduler_mode": "cfq",
"sectors": "2097151",
"sectorsize": "512",
"size": "1024.00 MB",
"support_discard": "0",
"vendor": "VBOX"
}
},
"ansible_distribution": "Ubuntu",
"ansible_distribution_release": "precise",
"ansible_distribution_version": "12.04",
"ansible_domain": "",
"ansible_eth0": {
"active": true,
"device": "eth0",
"ipv4": {
"address": "10.0.2.15",
"netmask": "255.255.255.0",
"network": "10.0.2.0"
},
"ipv6": [
{
"address": "fe80::a00:27ff:fe12:9698",
"prefix": "64",
"scope": "link"
}
],
"macaddress": "08:00:27:12:96:98",
"module": "e1000",
"mtu": 1500,
"type": "ether"
},
"ansible_eth1": {
"active": true,
"device": "eth1",
"ipv4": {
"address": "192.168.10.10",
"netmask": "255.255.255.0",
"network": "192.168.10.0"
},
"ipv6": [
{
"address": "fe80::a00:27ff:fe74:1330",
"prefix": "64",
"scope": "link"
}
],
"macaddress": "08:00:27:74:13:30",
"module": "e1000",
"mtu": 1500,
"type": "ether"
},
"ansible_form_factor": "Other",
"ansible_fqdn": "scdev",
"ansible_hostname": "scdev",
"ansible_interfaces": [
"lo",
"eth1",
"eth0"
],
"ansible_kernel": "3.2.0-23-generic-pae",
"ansible_lo": {
"active": true,
"device": "lo",
"ipv4": {
"address": "127.0.0.1",
"netmask": "255.0.0.0",
"network": "127.0.0.0"
},
"ipv6": [
{
"address": "::1",
"prefix": "128",
"scope": "host"
}
],
"mtu": 16436,
"type": "loopback"
},
"ansible_lsb": {
"codename": "precise",
"description": "Ubuntu 12.04 LTS",
"id": "Ubuntu",
"major_release": "12",
"release": "12.04"
},
"ansible_machine": "i686",
"ansible_memfree_mb": 23,
"ansible_memtotal_mb": 369,
"ansible_mounts": [
{
"device": "/dev/mapper/precise32-root",
"fstype": "ext4",
"mount": "/",
"options": "rw,errors=remount-ro",
"size_available": 77685088256,
"size_total": 84696281088
},
{
"device": "/dev/sda1",
"fstype": "ext2",
"mount": "/boot",
"options": "rw",
"size_available": 201044992,
"size_total": 238787584
},
{
"device": "/vagrant",
"fstype": "vboxsf",
"mount": "/vagrant",
"options": "uid=1000,gid=1000,rw",
"size_available": 42013151232,
"size_total": 484145360896
}
],
"ansible_os_family": "Debian",
"ansible_pkg_mgr": "apt",
"ansible_processor": [
"Pentium(R) Dual-Core CPU E5300 @ 2.60GHz"
],
"ansible_processor_cores": "NA",
"ansible_processor_count": 1,
"ansible_product_name": "VirtualBox",
"ansible_product_serial": "NA",
"ansible_product_uuid": "NA",
"ansible_product_version": "1.2",
"ansible_python_version": "2.7.3",
"ansible_selinux": false,
"ansible_swapfree_mb": 766,
"ansible_swaptotal_mb": 767,
"ansible_system": "Linux",
"ansible_system_vendor": "innotek GmbH",
"ansible_user_id": "neves",
"ansible_userspace_architecture": "i386",
"ansible_userspace_bits": "32",
"ansible_virtualization_role": "guest",
"ansible_virtualization_type": "virtualbox"
},
"changed": false
}
The current documentation now has a complete chapter listing all Variables and Facts
Default text which won't be shown in drop-down list
Kyle's solution worked perfectly fine for me so I made my research in order to avoid any Js and CSS, but just sticking with HTML.
Adding a value of selected to the item we want to appear as a header forces it to show in the first place as a placeholder.
Something like:
<option selected disabled>Choose here</option>
The complete markup should be along these lines:
<select>
<option selected disabled>Choose here</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
<option value="4">Four</option>
<option value="5">Five</option>
</select>
You can take a look at this fiddle, and here's the result:
If you do not want the sort of placeholder text to appear listed in the options once a user clicks on the select box just add the hidden attribute like so:
<select>
<option selected disabled hidden>Choose here</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
<option value="4">Four</option>
<option value="5">Five</option>
</select>
Check the fiddle here and the screenshot below.
Here is the solution:
<select>
<option style="display:none;" selected>Select language</option>
<option>Option 1</option>
<option>Option 2</option>
</select>
CodeIgniter: Create new helper?
Well for me only works adding the text "_helper" after in the php file like:
And to load automatically the helper in the folder aplication -> file autoload.php add in the array helper's the name without "_helper" like:
$autoload['helper'] = array('comunes');
And with that I can use all the helper's functions
Fatal error: Call to undefined function: ldap_connect()
Open the XAMMP php.ini file (the default path is C:\xammp\php\php.ini) and change the code (;extension=ldap) to extension=php_ldap.dll and save. Restart XAMMP and save.
php.ini
; Notes for Windows environments :
;
; - Many DLL files are located in the extensions/ (PHP 4) or ext/ (PHP 5+)
; extension folders as well as the separate PECL DLL download (PHP 5+).
; Be sure to appropriately set the extension_dir directive.
;
extension=bz2
extension=curl
extension=fileinfo
extension=gd2
extension=gettext
;extension=gmp
;extension=intl
;extension=imap
;extension=interbase
extension=php_ldap.dll
Decrypt password created with htpasswd
See in particular Apache HTTPd Password Formats
Git and nasty "error: cannot lock existing info/refs fatal"
You want to try doing:
git gc --prune=now
See https://www.kernel.org/pub/software/scm/git/docs/git-gc.html
What is a good practice to check if an environmental variable exists or not?
In case you want to check if multiple env variables are not set, you can do the following:
import os
MANDATORY_ENV_VARS = ["FOO", "BAR"]
for var in MANDATORY_ENV_VARS:
if var not in os.environ:
raise EnvironmentError("Failed because {} is not set.".format(var))
How to ignore deprecation warnings in Python
Try the below code if you're Using Python3:
import sys
if not sys.warnoptions:
import warnings
warnings.simplefilter("ignore")
or try this...
import warnings
def fxn():
warnings.warn("deprecated", DeprecationWarning)
with warnings.catch_warnings():
warnings.simplefilter("ignore")
fxn()
or try this...
import warnings
warnings.filterwarnings("ignore")
Implementing a Custom Error page on an ASP.Net website
There are 2 ways to configure custom error pages for ASP.NET sites:
- Internet Information Services (IIS) Manager (the GUI)
- web.config file
This article explains how to do each:
The reason your error.aspx page is not displaying might be because you have an error in your web.config. Try this instead:
<configuration>
<system.web>
<customErrors defaultRedirect="error.aspx" mode="RemoteOnly">
<error statusCode="404" redirect="error.aspx"/>
</customErrors>
</system.web>
</configuration>
You might need to make sure that Error Pages in IIS Manager - Feature Delegation is set to Read/Write:
Also, this answer may help you configure the web.config file:
Capture characters from standard input without waiting for enter to be pressed
You can do it portably using SDL (the Simple DirectMedia Library), though I suspect you may not like its behavior. When I tried it, I had to have SDL create a new video window (even though I didn't need it for my program) and have this window "grab" almost all keyboard and mouse input (which was okay for my usage but could be annoying or unworkable in other situations). I suspect it's overkill and not worth it unless complete portability is a must--otherwise try one of the other suggested solutions.
By the way, this will give you key press and release events separately, if you're into that.
How do I output an ISO 8601 formatted string in JavaScript?
If you don't need to support IE7, the following is a great, concise hack:
JSON.parse(JSON.stringify(new Date()))
ModalPopupExtender OK Button click event not firing?
I was just searching for a solution for this :)
it appears that you can't have OkControlID assign to a control if you want to that control fires an event, just removing this property I got everything working again.
my code (working):
<asp:Panel ID="pnlResetPanelsView" CssClass="modalPopup" runat="server" Style="display:none;">
<h2>
Warning</h2>
<p>
Do you really want to reset the panels to the default view?</p>
<div style="text-align: center;">
<asp:Button ID="btnResetPanelsViewOK" Width="60" runat="server" Text="Yes"
CssClass="buttonSuperOfficeLayout" OnClick="btnResetPanelsViewOK_Click" />
<asp:Button ID="btnResetPanelsViewCancel" Width="60" runat="server" Text="No" CssClass="buttonSuperOfficeLayout" />
</div>
</asp:Panel>
<ajax:ModalPopupExtender ID="mpeResetPanelsView" runat="server" TargetControlID="btnResetView"
PopupControlID="pnlResetPanelsView" BackgroundCssClass="modalBackground" DropShadow="true"
CancelControlID="btnResetPanelsViewCancel" />
Can Keras with Tensorflow backend be forced to use CPU or GPU at will?
For people working on PyCharm, and for forcing CPU, you can add the following line in the Run/Debug configuration, under Environment variables:
<OTHER_ENVIRONMENT_VARIABLES>;CUDA_VISIBLE_DEVICES=-1
How to change background color of cell in table using java script
document.getElementById('id1').bgColor = '#00FF00';
seems to work. I don't think .style.backgroundColor does.
YouTube API to fetch all videos on a channel
Try with like the following. It may help you.
https://gdata.youtube.com/feeds/api/videos?author=cnn&v=2&orderby=updated&alt=jsonc&q=news
Here author as you can specify your channel name and "q" as you can give your search key word.
send/post xml file using curl command line
Here's how you can POST XML on Windows using curl command line on Windows. Better use batch/.cmd file for that:
curl -i -X POST -H "Content-Type: text/xml" -d ^
"^<?xml version=\"1.0\" encoding=\"UTF-8\" ?^> ^
^<Transaction^> ^
^<SomeParam1^>Some-Param-01^</SomeParam1^> ^
^<Password^>SomePassW0rd^</Password^> ^
^<Transaction_Type^>00^</Transaction_Type^> ^
^<CardHoldersName^>John Smith^</CardHoldersName^> ^
^<DollarAmount^>9.97^</DollarAmount^> ^
^<Card_Number^>4111111111111111^</Card_Number^> ^
^<Expiry_Date^>1118^</Expiry_Date^> ^
^<VerificationStr2^>123^</VerificationStr2^> ^
^<CVD_Presence_Ind^>1^</CVD_Presence_Ind^> ^
^<Reference_No^>Some Reference Text^</Reference_No^> ^
^<Client_Email^>[email protected]^</Client_Email^> ^
^<Client_IP^>123.4.56.7^</Client_IP^> ^
^<Tax1Amount^>^</Tax1Amount^> ^
^<Tax2Amount^>^</Tax2Amount^> ^
^</Transaction^> ^
" "http://localhost:8080"
Using a SELECT statement within a WHERE clause
Subquery is the name.
At times it's required, but good/bad depends on how it's applied.
How to achieve pagination/table layout with Angular.js?
I use this solution:
It's a bit more concise since I use: ng-repeat="obj in objects | filter : paginate" to filter the rows. Also made it working with $resource:
How to start http-server locally
When you're running npm install in the project's root, it installs all of the npm dependencies into the project's node_modules directory.
If you take a look at the project's node_modules directory, you should see a directory called http-server, which holds the http-server package, and a .bin folder, which holds the executable binaries from the installed dependencies. The .bin directory should have the http-server binary (or a link to it).
So in your case, you should be able to start the http-server by running the following from your project's root directory (instead of npm start):
./node_modules/.bin/http-server -a localhost -p 8000 -c-1
This should have the same effect as running npm start.
If you're running a Bash shell, you can simplify this by adding the ./node_modules/.bin folder to your $PATH environment variable:
export PATH=./node_modules/.bin:$PATH
This will put this folder on your path, and you should be able to simply run
http-server -a localhost -p 8000 -c-1
How can I add a hint or tooltip to a label in C# Winforms?
just another way to do it.
Label lbl = new Label();
new ToolTip().SetToolTip(lbl, "tooltip text here");
angularjs: allows only numbers to be typed into a text box
Based on djsiz solution, wrapped in directive. NOTE: it will not handle digit numbers, but it can be easily updated
angular
.module("app")
.directive("mwInputRestrict", [
function () {
return {
restrict: "A",
link: function (scope, element, attrs) {
element.on("keypress", function (event) {
if (attrs.mwInputRestrict === "onlynumbers") {
// allow only digits to be entered, or backspace and delete keys to be pressed
return (event.charCode >= 48 && event.charCode <= 57) ||
(event.keyCode === 8 || event.keyCode === 46);
}
return true;
});
}
}
}
]);
HTML
<input type="text"
class="form-control"
id="inputHeight"
name="inputHeight"
placeholder="Height"
mw-input-restrict="onlynumbers"
ng-model="ctbtVm.dto.height">
Programmatically trigger "select file" dialog box
For those who want the same but are using React
openFileInput = () => {
this.fileInput.click()
}
<a href="#" onClick={this.openFileInput}>
<p>Carregue sua foto de perfil</p>
<img src={img} />
</a>
<input style={{display:'none'}} ref={(input) => { this.fileInput = input; }} type="file"/>
how to define ssh private key for servers fetched by dynamic inventory in files
The best solution I could find for this problem is to specify private key file in ansible.cfg (I usually keep it in the same folder as a playbook):
[defaults]
inventory=ec2.py
vault_password_file = ~/.vault_pass.txt
host_key_checking = False
private_key_file = /Users/eric/.ssh/secret_key_rsa
Though, it still sets private key globally for all hosts in playbook.
Note: You have to specify full path to the key file - ~user/.ssh/some_key_rsa silently ignored.
Retrieve last 100 lines logs
Look, the sed script that prints the 100 last lines you can find in the documentation for sed (https://www.gnu.org/software/sed/manual/sed.html#tail):
$ cat sed.cmd
1! {; H; g; }
1,100 !s/[^\n]*\n//
$p
$ sed -nf sed.cmd logfilename
For me it is way more difficult than your script so
tail -n 100 logfilename
is much much simpler. And it is quite efficient, it will not read all file if it is not necessary. See my answer with strace report for tail ./huge-file: https://unix.stackexchange.com/questions/102905/does-tail-read-the-whole-file/102910#102910
Difference between string and char[] types in C++
Strings have helper functions and manage char arrays automatically. You can concatenate strings, for a char array you would need to copy it to a new array, strings can change their length at runtime. A char array is harder to manage than a string and certain functions may only accept a string as input, requiring you to convert the array to a string. It's better to use strings, they were made so that you don't have to use arrays. If arrays were objectively better we wouldn't have strings.
Append date to filename in linux
I use this script in bash:
#!/bin/bash
now=$(date +"%b%d-%Y-%H%M%S")
FILE="$1"
name="${FILE%.*}"
ext="${FILE##*.}"
cp -v $FILE $name-$now.$ext
This script copies filename.ext to filename-date.ext, there is another that moves filename.ext to filename-date.ext, you can download them from here. Hope you find them useful!!
Getting the last n elements of a vector. Is there a better way than using the length() function?
Here is a function to do it and seems reasonably fast.
endv<-function(vec,val)
{
if(val>length(vec))
{
stop("Length of value greater than length of vector")
}else
{
vec[((length(vec)-val)+1):length(vec)]
}
}
USAGE:
test<-c(0,1,1,0,0,1,1,NA,1,1)
endv(test,5)
endv(LETTERS,5)
BENCHMARK:
test replications elapsed relative
1 expression(tail(x, 5)) 100000 5.24 6.469
2 expression(x[seq.int(to = length(x), length.out = 5)]) 100000 0.98 1.210
3 expression(x[length(x) - (4:0)]) 100000 0.81 1.000
4 expression(endv(x, 5)) 100000 1.37 1.691
Error : ORA-01704: string literal too long
The split work until 4000 chars depending on the characters that you are inserting. If you are inserting special characters it can fail. The only secure way is to declare a variable.
How to stop the Timer in android?
and.. we must call "waitTimer.purge()" for the GC. If you don't use Timer anymore, "purge()" !! "purge()" removes all canceled tasks from the task queue.
if(waitTimer != null) {
waitTimer.cancel();
waitTimer.purge();
waitTimer = null;
}
Delete all but the most recent X files in bash
Removes all but the 10 latest (most recents) files
ls -t1 | head -n $(echo $(ls -1 | wc -l) - 10 | bc) | xargs rm
If less than 10 files no file is removed and you will have : error head: illegal line count -- 0
What is the difference between a strongly typed language and a statically typed language?
Data Coercion does not necessarily mean weakly typed because sometimes its syntacical sugar:
The example above of Java being weakly typed because of
String s = "abc" + 123;
Is not weakly typed example because its really doing:
String s = "abc" + new Integer(123).toString()
Data coercion is also not weakly typed if you are constructing a new object. Java is a very bad example of weakly typed (and any language that has good reflection will most likely not be weakly typed). Because the runtime of the language always knows what the type is (the exception might be native types).
This is unlike C. C is the one of the best examples of weakly typed. The runtime has no idea if 4 bytes is an integer, a struct, a pointer or a 4 characters.
The runtime of the language really defines whether or not its weakly typed otherwise its really just opinion.
EDIT: After further thought this is not necessarily true as the runtime does not have to have all the types reified in the runtime system to be a Strongly Typed system. Haskell and ML have such complete static analysis that they can potential ommit type information from the runtime.
What does AngularJS do better than jQuery?
Data-Binding
You go around making your webpage, and keep on putting {{data bindings}} whenever you feel you would have dynamic data. Angular will then provide you a $scope handler, which you can populate (statically or through calls to the web server).
This is a good understanding of data-binding. I think you've got that down.
DOM Manipulation
For simple DOM manipulation, which doesnot involve data manipulation (eg: color changes on mousehover, hiding/showing elements on click), jQuery or old-school js is sufficient and cleaner. This assumes that the model in angular's mvc is anything that reflects data on the page, and hence, css properties like color, display/hide, etc changes dont affect the model.
I can see your point here about "simple" DOM manipulation being cleaner, but only rarely and it would have to be really "simple". I think DOM manipulation is one the areas, just like data-binding, where Angular really shines. Understanding this will also help you see how Angular considers its views.
I'll start by comparing the Angular way with a vanilla js approach to DOM manipulation. Traditionally, we think of HTML as not "doing" anything and write it as such. So, inline js, like "onclick", etc are bad practice because they put the "doing" in the context of HTML, which doesn't "do". Angular flips that concept on its head. As you're writing your view, you think of HTML as being able to "do" lots of things. This capability is abstracted away in angular directives, but if they already exist or you have written them, you don't have to consider "how" it is done, you just use the power made available to you in this "augmented" HTML that angular allows you to use. This also means that ALL of your view logic is truly contained in the view, not in your javascript files. Again, the reasoning is that the directives written in your javascript files could be considered to be increasing the capability of HTML, so you let the DOM worry about manipulating itself (so to speak). I'll demonstrate with a simple example.
This is the markup we want to use. I gave it an intuitive name.
<div rotate-on-click="45"></div>
First, I'd just like to comment that if we've given our HTML this functionality via a custom Angular Directive, we're already done. That's a breath of fresh air. More on that in a moment.
Implementation with jQuery
function rotate(deg, elem) {
$(elem).css({
webkitTransform: 'rotate('+deg+'deg)',
mozTransform: 'rotate('+deg+'deg)',
msTransform: 'rotate('+deg+'deg)',
oTransform: 'rotate('+deg+'deg)',
transform: 'rotate('+deg+'deg)'
});
}
function addRotateOnClick($elems) {
$elems.each(function(i, elem) {
var deg = 0;
$(elem).click(function() {
deg+= parseInt($(this).attr('rotate-on-click'), 10);
rotate(deg, this);
});
});
}
addRotateOnClick($('[rotate-on-click]'));
Implementation with Angular
app.directive('rotateOnClick', function() {
return {
restrict: 'A',
link: function(scope, element, attrs) {
var deg = 0;
element.bind('click', function() {
deg+= parseInt(attrs.rotateOnClick, 10);
element.css({
webkitTransform: 'rotate('+deg+'deg)',
mozTransform: 'rotate('+deg+'deg)',
msTransform: 'rotate('+deg+'deg)',
oTransform: 'rotate('+deg+'deg)',
transform: 'rotate('+deg+'deg)'
});
});
}
};
});
Pretty light, VERY clean and that's just a simple manipulation! In my opinion, the angular approach wins in all regards, especially how the functionality is abstracted away and the dom manipulation is declared in the DOM. The functionality is hooked onto the element via an html attribute, so there is no need to query the DOM via a selector, and we've got two nice closures - one closure for the directive factory where variables are shared across all usages of the directive, and one closure for each usage of the directive in the link function (or compile function).
Two-way data binding and directives for DOM manipulation are only the start of what makes Angular awesome. Angular promotes all code being modular, reusable, and easily testable and also includes a single-page app routing system. It is important to note that jQuery is a library of commonly needed convenience/cross-browser methods, but Angular is a full featured framework for creating single page apps. The angular script actually includes its own "lite" version of jQuery so that some of the most essential methods are available. Therefore, you could argue that using Angular IS using jQuery (lightly), but Angular provides much more "magic" to help you in the process of creating apps.
This is a great post for more related information: How do I “think in AngularJS” if I have a jQuery background?
General differences.
The above points are aimed at the OP's specific concerns. I'll also give an overview of the other important differences. I suggest doing additional reading about each topic as well.
Angular and jQuery can't reasonably be compared.
Angular is a framework, jQuery is a library. Frameworks have their place and libraries have their place. However, there is no question that a good framework has more power in writing an application than a library. That's exactly the point of a framework. You're welcome to write your code in plain JS, or you can add in a library of common functions, or you can add a framework to drastically reduce the code you need to accomplish most things. Therefore, a more appropriate question is:
Why use a framework?
Good frameworks can help architect your code so that it is modular (therefore reusable), DRY, readable, performant and secure. jQuery is not a framework, so it doesn't help in these regards. We've all seen the typical walls of jQuery spaghetti code. This isn't jQuery's fault - it's the fault of developers that don't know how to architect code. However, if the devs did know how to architect code, they would end up writing some kind of minimal "framework" to provide the foundation (achitecture, etc) I discussed a moment ago, or they would add something in. For example, you might add RequireJS to act as part of your framework for writing good code.
Here are some things that modern frameworks are providing:
- Templating
- Data-binding
- routing (single page app)
- clean, modular, reusable architecture
- security
- additional functions/features for convenience
Before I further discuss Angular, I'd like to point out that Angular isn't the only one of its kind. Durandal, for example, is a framework built on top of jQuery, Knockout, and RequireJS. Again, jQuery cannot, by itself, provide what Knockout, RequireJS, and the whole framework built on top them can. It's just not comparable.
If you need to destroy a planet and you have a Death Star, use the Death star.
Angular (revisited).
Building on my previous points about what frameworks provide, I'd like to commend the way that Angular provides them and try to clarify why this is matter of factually superior to jQuery alone.
DOM reference.
In my above example, it is just absolutely unavoidable that jQuery has to hook onto the DOM in order to provide functionality. That means that the view (html) is concerned about functionality (because it is labeled with some kind of identifier - like "image slider") and JavaScript is concerned about providing that functionality. Angular eliminates that concept via abstraction. Properly written code with Angular means that the view is able to declare its own behavior. If I want to display a clock:
<clock></clock>
Done.
Yes, we need to go to JavaScript to make that mean something, but we're doing this in the opposite way of the jQuery approach. Our Angular directive (which is in it's own little world) has "augumented" the html and the html hooks the functionality into itself.
MVW Architecure / Modules / Dependency Injection
Angular gives you a straightforward way to structure your code. View things belong in the view (html), augmented view functionality belongs in directives, other logic (like ajax calls) and functions belong in services, and the connection of services and logic to the view belongs in controllers. There are some other angular components as well that help deal with configuration and modification of services, etc. Any functionality you create is automatically available anywhere you need it via the Injector subsystem which takes care of Dependency Injection throughout the application. When writing an application (module), I break it up into other reusable modules, each with their own reusable components, and then include them in the bigger project. Once you solve a problem with Angular, you've automatically solved it in a way that is useful and structured for reuse in the future and easily included in the next project. A HUGE bonus to all of this is that your code will be much easier to test.
It isn't easy to make things "work" in Angular.
THANK GOODNESS. The aforementioned jQuery spaghetti code resulted from a dev that made something "work" and then moved on. You can write bad Angular code, but it's much more difficult to do so, because Angular will fight you about it. This means that you have to take advantage (at least somewhat) to the clean architecture it provides. In other words, it's harder to write bad code with Angular, but more convenient to write clean code.
Angular is far from perfect. The web development world is always growing and changing and there are new and better ways being put forth to solve problems. Facebook's React and Flux, for example, have some great advantages over Angular, but come with their own drawbacks. Nothing's perfect, but Angular has been and is still awesome for now. Just as jQuery once helped the web world move forward, so has Angular, and so will many to come.
How to view .img files?
If you use Linux or WSL you can use the forensic application binwalk to extract .img files (which are usually disk images) like this:
Use your distribution package manager or follow the manual instructions to install binwalk.
Use the command
binwalk -e FILENAME.imgto extract recognized content into a automatically generated directory.
Programmatically generate video or animated GIF in Python?
Like Warren said last year, this is an old question. Since people still seem to be viewing the page, I'd like to redirect them to a more modern solution. Like blakev said here, there is a Pillow example on github.
import ImageSequence
import Image
import gifmaker
sequence = []
im = Image.open(....)
# im is your original image
frames = [frame.copy() for frame in ImageSequence.Iterator(im)]
# write GIF animation
fp = open("out.gif", "wb")
gifmaker.makedelta(fp, frames)
fp.close()
Note: This example is outdated (gifmaker is not an importable module, only a script). Pillow has a GifImagePlugin (whose source is on GitHub), but the doc on ImageSequence seems to indicate limited support (reading only)
What does it mean: The serializable class does not declare a static final serialVersionUID field?
The other answers so far have a lot of technical information. I will try to answer, as requested, in simple terms.
Serialization is what you do to an instance of an object if you want to dump it to a raw buffer, save it to disk, transport it in a binary stream (e.g., sending an object over a network socket), or otherwise create a serialized binary representation of an object. (For more info on serialization see Java Serialization on Wikipedia).
If you have no intention of serializing your class, you can add the annotation just above your class @SuppressWarnings("serial").
If you are going to serialize, then you have a host of things to worry about all centered around the proper use of UUID. Basically, the UUID is a way to "version" an object you would serialize so that whatever process is de-serializing knows that it's de-serializing properly. I would look at Ensure proper version control for serialized objects for more information.
Python-Requests close http connection
As discussed here, there really isn't such a thing as an HTTP connection and what httplib refers to as the HTTPConnection is really the underlying TCP connection which doesn't really know much about your requests at all. Requests abstracts that away and you won't ever see it.
The newest version of Requests does in fact keep the TCP connection alive after your request.. If you do want your TCP connections to close, you can just configure the requests to not use keep-alive.
s = requests.session()
s.config['keep_alive'] = False
How to assert two list contain the same elements in Python?
Slightly faster version of the implementation (If you know that most couples lists will have different lengths):
def checkEqual(L1, L2):
return len(L1) == len(L2) and sorted(L1) == sorted(L2)
Comparing:
>>> timeit(lambda: sorting([1,2,3], [3,2,1]))
2.42745304107666
>>> timeit(lambda: lensorting([1,2,3], [3,2,1]))
2.5644469261169434 # speed down not much (for large lists the difference tends to 0)
>>> timeit(lambda: sorting([1,2,3], [3,2,1,0]))
2.4570400714874268
>>> timeit(lambda: lensorting([1,2,3], [3,2,1,0]))
0.9596951007843018 # speed up
How to use find command to find all files with extensions from list?
find /path -type f \( -iname "*.jpg" -o -name "*.jpeg" -o -iname "*gif" \)
How do I call a non-static method from a static method in C#?
You'll need to create an instance of the class and invoke the method on it.
public class Foo
{
public void Data1()
{
}
public static void Data2()
{
Foo foo = new Foo();
foo.Data1();
}
}
Component based game engine design
Interesting artcle...
I've had a quick hunt around on google and found nothing, but you might want to check some of the comments - plenty of people seem to have had a go at implementing a simple component demo, you might want to take a look at some of theirs for inspiration:
http://www.unseen-academy.de/componentSystem.html
http://www.mcshaffry.com/GameCode/thread.php?threadid=732
http://www.codeplex.com/Wikipage?ProjectName=elephant
Also, the comments themselves seem to have a fairly in-depth discussion on how you might code up such a system.
Why should I prefer to use member initialization lists?
For POD class members, it makes no difference, it's just a matter of style. For class members which are classes, then it avoids an unnecessary call to a default constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the constructor for B will call the default constructor for A, and then initialize a.x to 3. A better way would be for B's constructor to directly call A's constructor in the initializer list:
B()
: a(3)
{
}
This would only call A's A(int) constructor and not its default constructor. In this example, the difference is negligible, but imagine if you will that A's default constructor did more, such as allocating memory or opening files. You wouldn't want to do that unnecessarily.
Furthermore, if a class doesn't have a default constructor, or you have a const member variable, you must use an initializer list:
class A
{
public:
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B() : a(3), y(2) // 'a' and 'y' MUST be initialized in an initializer list;
{ // it is an error not to do so
}
private:
A a;
const int y;
};
How to get the first word of a sentence in PHP?
Using split function also you can get the first word from string.
<?php
$myvalue ="Test me more";
$result=split(" ",$myvalue);
echo $result[0];
?>
how can I copy a conditional formatting in Excel 2010 to other cells, which is based on a other cells content?
I ran into the same situation where when I copied the formula to another cell the formula was still referencing the cell used in the first formula. To correct this when you set up the rules, select the option "use a formula to determine which cells to format. Then type in the box your formula, for example H23*.25. When you copy the cells down the formulas will change to H24*.25, H25*.25 and so on. Hope this helps.
How to make an Android Spinner with initial text "Select One"?
I found this solution:
String[] items = new String[] {"Select One", "Two", "Three"};
Spinner spinner = (Spinner) findViewById(R.id.mySpinner);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, items);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(adapter);
spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> arg0, View arg1, int position, long id) {
items[0] = "One";
selectedItem = items[position];
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
Just change the array[0] with "Select One" and then in the onItemSelected, rename it to "One".
Not a classy solution, but it works :D
How to add data to DataGridView
LINQ is a "query" language (thats the Q), so modifying data is outside its scope.
That said, your DataGridView is presumably bound to an ItemsSource, perhaps of type ObservableCollection<T> or similar. In that case, just do something like X.ToList().ForEach(yourGridSource.Add) (this might have to be adapted based on the type of source in your grid).
Add comma to numbers every three digits
You can also look at the jquery FormatCurrency plugin (of which I am the author); it has support for multiple locales as well, but may have the overhead of the currency support that you don't need.
$(this).formatCurrency({ symbol: '', roundToDecimalPlace: 0 });
How to define custom sort function in javascript?
function msort(arr){
for(var i =0;i<arr.length;i++){
for(var j= i+1;j<arr.length;j++){
if(arr[i]>arr[j]){
var swap = arr[i];
arr[i] = arr[j];
arr[j] = swap;
}
}
}
return arr;
}
How do I force make/GCC to show me the commands?
Build system independent method
make SHELL='sh -x'
is another option. Sample Makefile:
a:
@echo a
Output:
+ echo a
a
This sets the special SHELL variable for make, and -x tells sh to print the expanded line before executing it.
One advantage over -n is that is actually runs the commands. I have found that for some projects (e.g. Linux kernel) that -n may stop running much earlier than usual probably because of dependency problems.
One downside of this method is that you have to ensure that the shell that will be used is sh, which is the default one used by Make as they are POSIX, but could be changed with the SHELL make variable.
Doing sh -v would be cool as well, but Dash 0.5.7 (Ubuntu 14.04 sh) ignores for -c commands (which seems to be how make uses it) so it doesn't do anything.
make -p will also interest you, which prints the values of set variables.
CMake generated Makefiles always support VERBOSE=1
As in:
mkdir build
cd build
cmake ..
make VERBOSE=1
Dedicated question at: Using CMake with GNU Make: How can I see the exact commands?
How do you determine the ideal buffer size when using FileInputStream?
In BufferedInputStream‘s source you will find: private static int DEFAULT_BUFFER_SIZE = 8192;
So it's okey for you to use that default value.
But if you can figure out some more information you will get more valueable answers.
For example, your adsl maybe preffer a buffer of 1454 bytes, thats because TCP/IP's payload. For disks, you may use a value that match your disk's block size.
Automatically scroll down chat div
Let's review a few useful concepts about scrolling first:
- scrollHeight: total container size.
- scrollTop: amount of scroll user has done.
- clientHeight: amount of container a user sees.
When should you scroll?
- User has loaded messages for the first time.
- New messages have arrived and you are at the bottom of the scroll (you don't want to force scroll when the user is scrolling up to read previous messages).
Programmatically that is:
if (firstTime) {
container.scrollTop = container.scrollHeight;
firstTime = false;
} else if (container.scrollTop + container.clientHeight === container.scrollHeight) {
container.scrollTop = container.scrollHeight;
}
Full chat simulator (with JavaScript):
https://jsfiddle.net/apvtL9xa/
const messages = document.getElementById('messages');_x000D_
_x000D_
function appendMessage() {_x000D_
const message = document.getElementsByClassName('message')[0];_x000D_
const newMessage = message.cloneNode(true);_x000D_
messages.appendChild(newMessage);_x000D_
}_x000D_
_x000D_
function getMessages() {_x000D_
// Prior to getting your messages._x000D_
shouldScroll = messages.scrollTop + messages.clientHeight === messages.scrollHeight;_x000D_
/*_x000D_
* Get your messages, we'll just simulate it by appending a new one syncronously._x000D_
*/_x000D_
appendMessage();_x000D_
// After getting your messages._x000D_
if (!shouldScroll) {_x000D_
scrollToBottom();_x000D_
}_x000D_
}_x000D_
_x000D_
function scrollToBottom() {_x000D_
messages.scrollTop = messages.scrollHeight;_x000D_
}_x000D_
_x000D_
scrollToBottom();_x000D_
_x000D_
setInterval(getMessages, 100);#messages {_x000D_
height: 200px;_x000D_
overflow-y: auto;_x000D_
}<div id="messages">_x000D_
<div class="message">_x000D_
Hello world_x000D_
</div>_x000D_
</div>How to send file contents as body entity using cURL
In my case, @ caused some sort of encoding problem, I still prefer my old way:
curl -d "$(cat /path/to/file)" https://example.com
Flex-box: Align last row to grid
I was able to do it with justify-content: space-between on the container
Testing for empty or nil-value string
variable = id if variable.to_s.empty?
Jenkins: Is there any way to cleanup Jenkins workspace?
IMPORTANT: It is safe to remove the workspace for a given Jenkins job as long as the job is not currently running!
NOTE: I am assuming your $JENKINS_HOME is set to the default: /var/jenkins_home.
Clean up one workspace
rm -rf /var/jenkins_home/workspaces/<workspace>
Clean up all workspaces
rm -rf /var/jenkins_home/workspaces/*
Clean up all workspaces with a few exceptions
This one uses grep to create a whitelist:
ls /var/jenkins_home/workspace \
| grep -v -E '(job-to-skip|another-job-to-skip)$' \
| xargs -I {} rm -rf /var/jenkins_home/workspace/{}
Clean up 10 largest workspaces
This one uses du and sort to list workspaces in order of largest to smallest. Then, it uses head to grab the first 10:
du -d 1 /var/jenkins_home/workspace \
| sort -n -r \
| head -n 10 \
| xargs -I {} rm -rf /var/jenkins_home/workspace/{}
Determine on iPhone if user has enabled push notifications
Call enabledRemoteNotificationsTypes and check the mask.
For example:
UIRemoteNotificationType types = [[UIApplication sharedApplication] enabledRemoteNotificationTypes];
if (types == UIRemoteNotificationTypeNone)
// blah blah blah
iOS8 and above:
[[UIApplication sharedApplication] isRegisteredForRemoteNotifications]
Any way to make plot points in scatterplot more transparent in R?
Transparency can be coded in the color argument as well. It is just two more hex numbers coding a transparency between 0 (fully transparent) and 255 (fully visible). I once wrote this function to add transparency to a color vector, maybe it is usefull here?
addTrans <- function(color,trans)
{
# This function adds transparancy to a color.
# Define transparancy with an integer between 0 and 255
# 0 being fully transparant and 255 being fully visable
# Works with either color and trans a vector of equal length,
# or one of the two of length 1.
if (length(color)!=length(trans)&!any(c(length(color),length(trans))==1)) stop("Vector lengths not correct")
if (length(color)==1 & length(trans)>1) color <- rep(color,length(trans))
if (length(trans)==1 & length(color)>1) trans <- rep(trans,length(color))
num2hex <- function(x)
{
hex <- unlist(strsplit("0123456789ABCDEF",split=""))
return(paste(hex[(x-x%%16)/16+1],hex[x%%16+1],sep=""))
}
rgb <- rbind(col2rgb(color),trans)
res <- paste("#",apply(apply(rgb,2,num2hex),2,paste,collapse=""),sep="")
return(res)
}
Some examples:
cols <- sample(c("red","green","pink"),100,TRUE)
# Fully visable:
plot(rnorm(100),rnorm(100),col=cols,pch=16,cex=4)
# Somewhat transparant:
plot(rnorm(100),rnorm(100),col=addTrans(cols,200),pch=16,cex=4)
# Very transparant:
plot(rnorm(100),rnorm(100),col=addTrans(cols,100),pch=16,cex=4)
Iterating each character in a string using Python
If you would like to use a more functional approach to iterating over a string (perhaps to transform it somehow), you can split the string into characters, apply a function to each one, then join the resulting list of characters back into a string.
A string is inherently a list of characters, hence 'map' will iterate over the string - as second argument - applying the function - the first argument - to each one.
For example, here I use a simple lambda approach since all I want to do is a trivial modification to the character: here, to increment each character value:
>>> ''.join(map(lambda x: chr(ord(x)+1), "HAL"))
'IBM'
or more generally:
>>> ''.join(map(my_function, my_string))
where my_function takes a char value and returns a char value.
How to center a Window in Java?
You could try this also.
Frame frame = new Frame("Centered Frame");
Dimension dimemsion = Toolkit.getDefaultToolkit().getScreenSize();
frame.setLocation(dimemsion.width/2-frame.getSize().width/2, dimemsion.height/2-frame.getSize().height/2);
%Like% Query in spring JpaRepository
You can have one alternative of using placeholders as:
@Query("Select c from Registration c where c.place LIKE %?1%")
List<Registration> findPlaceContainingKeywordAnywhere(String place);
What is Cache-Control: private?
RFC 2616, section 14.9.1:
Indicates that all or part of the response message is intended for a single user and MUST NOT be cached by a shared cache...A private (non-shared) cache MAY cache the response.
Browsers could use this information. Of course, the current "user" may mean many things: OS user, a browser user (e.g. Chrome's profiles), etc. It's not specified.
For me, a more concrete example of Cache-Control: private is that proxy servers (which typically have many users) won't cache it. It is meant for the end user, and no one else.
FYI, the RFC makes clear that this does not provide security. It is about showing the correct content, not securing content.
This usage of the word private only controls where the response may be cached, and cannot ensure the privacy of the message content.
How can I pair socks from a pile efficiently?
I've finished pairing my socks just right now, and I found that the best way to do it is the following:
- Choose one of the socks and put it away (create a 'bucket' for that pair)
- If the next one is the pair of the previous one, then put it to the existing bucket, otherwise create a new one.
In the worst case it means that you will have n/2 different buckets, and you will have n-2 determinations about that which bucket contains the pair of the current sock. Obviously, this algorithm works well if you have just a few pairs; I did it with 12 pairs.
It is not so scientific, but it works well:)
Different class for the last element in ng-repeat
<div ng-repeat="file in files" ng-class="!$last ? 'class-for-last' : 'other'">
{{file.name}}
</div>
That works for me! Good luck!
Writelines writes lines without newline, Just fills the file
As others have noted, writelines is a misnomer (it ridiculously does not add newlines to the end of each line).
To do that, explicitly add it to each line:
with open(dst_filename, 'w') as f:
f.writelines(s + '\n' for s in lines)
C# JSON Serialization of Dictionary into {key:value, ...} instead of {key:key, value:value, ...}
Unfortunately, this is not currently possible in the latest version of DataContractJsonSerializer. See: http://connect.microsoft.com/VisualStudio/feedback/details/558686/datacontractjsonserializer-should-serialize-dictionary-k-v-as-a-json-associative-array
The current suggested workaround is to use the JavaScriptSerializer as Mark suggested above.
Good luck!
How to get the number of days of difference between two dates on mysql?
What about the DATEDIFF function ?
Quoting the manual's page :
DATEDIFF() returns expr1 – expr2 expressed as a value in days from one date to the other. expr1 and expr2 are date or date-and-time expressions. Only the date parts of the values are used in the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------------------------------+
1 row in set (0,00 sec)
But note the dates should be written as YYYY-MM-DD, and not DD-MM-YYYY like you posted.
How to remove items from a list while iterating?
Most of the answers here want you to create a copy of the list. I had a use case where the list was quite long (110K items) and it was smarter to keep reducing the list instead.
First of all you'll need to replace foreach loop with while loop,
i = 0
while i < len(somelist):
if determine(somelist[i]):
del somelist[i]
else:
i += 1
The value of i is not changed in the if block because you'll want to get value of the new item FROM THE SAME INDEX, once the old item is deleted.
Finding all possible permutations of a given string in python
def permute_all_chars(list, begin, end):
if (begin == end):
print(list)
return
for current_position in range(begin, end + 1):
list[begin], list[current_position] = list[current_position], list[begin]
permute_all_chars(list, begin + 1, end)
list[begin], list[current_position] = list[current_position], list[begin]
given_str = 'ABC'
list = []
for char in given_str:
list.append(char)
permute_all_chars(list, 0, len(list) -1)
Java unsupported major minor version 52.0
Your code was compiled with Java Version 1.8 while it is being executed with Java Version 1.7 or below.
In your case it seems that two different Java installations are used, the newer to compile and the older to execute your code.
Try recompiling your code with Java 1.7 or upgrade your Java Plugin.
Graphical user interface Tutorial in C
My favourite UI tutorials all come from zetcode.com:
- wxWidgets (C++, cross platform)
- Win32api GUI (C, Windows)
- GTK+ (C, cross platform)
- Qt4 Tutorial (C++, cross platform)
These are tutorials I'd consider to be "starting tutorials". The example tutorial gets you up and going, but doesn't show you anything too advanced or give much explanation. Still, often, I find the big problem is "how do I start?" and these have always proved useful to me.
Get the last non-empty cell in a column in Google Sheets
There may be a more eloquent way, but this is the way I came up with:
The function to find the last populated cell in a column is:
=INDEX( FILTER( A:A ; NOT( ISBLANK( A:A ) ) ) ; ROWS( FILTER( A:A ; NOT( ISBLANK( A:A ) ) ) ) )
So if you combine it with your current function it would look like this:
=DAYS360(A2,INDEX( FILTER( A:A ; NOT( ISBLANK( A:A ) ) ) ; ROWS( FILTER( A:A ; NOT( ISBLANK( A:A ) ) ) ) ))
MVC4 StyleBundle not resolving images
According to this thread on MVC4 css bundling and image references, if you define your bundle as:
bundles.Add(new StyleBundle("~/Content/css/jquery-ui/bundle")
.Include("~/Content/css/jquery-ui/*.css"));
Where you define the bundle on the same path as the source files that made up the bundle, the relative image paths will still work. The last part of the bundle path is really the file name for that specific bundle (i.e., /bundle can be any name you like).
This will only work if you are bundling together CSS from the same folder (which I think makes sense from a bundling perspective).
Update
As per the comment below by @Hao Kung, alternatively this may now be achieved by applying a CssRewriteUrlTransformation (Change relative URL references to CSS files when bundled).
NOTE: I have not confirmed comments regarding issues with rewriting to absolute paths within a virtual directory, so this may not work for everyone (?).
bundles.Add(new StyleBundle("~/Content/css/jquery-ui/bundle")
.Include("~/Content/css/jquery-ui/*.css",
new CssRewriteUrlTransform()));
Python: Finding differences between elements of a list
Using the := walrus operator available in Python 3.8+:
>>> t = [1, 3, 6]
>>> prev = t[0]; [-prev + (prev := x) for x in t[1:]]
[2, 3]
Is it possible to return empty in react render function?
Some answers are slightly incorrect and point to the wrong part of the docs:
If you want a component to render nothing, just return null, as per doc:
In rare cases you might want a component to hide itself even though it was rendered by another component. To do this return null instead of its render output.
If you try to return undefined for example, you'll get the following error:
Nothing was returned from render. This usually means a return statement is missing. Or, to render nothing, return null.
As pointed out by other answers, null, true, false and undefined are valid children which is useful for conditional rendering inside your jsx, but it you want your component to hide / render nothing, just return null.
Can I extend a class using more than 1 class in PHP?
If you really want to fake multiple inheritance in PHP 5.3, you can use the magic function __call().
This is ugly though it works from class A user's point of view :
class B {
public function method_from_b($s) {
echo $s;
}
}
class C {
public function method_from_c($s) {
echo $s;
}
}
class A extends B
{
private $c;
public function __construct()
{
$this->c = new C;
}
// fake "extends C" using magic function
public function __call($method, $args)
{
$this->c->$method($args[0]);
}
}
$a = new A;
$a->method_from_b("abc");
$a->method_from_c("def");
Prints "abcdef"
Your configuration specifies to merge with the <branch name> from the remote, but no such ref was fetched.?
This is a more common error now as many projects are moving their master branch to another name like main, primary, default, root, reference, latest, etc, as discussed at Github plans to replace racially insensitive terms like ‘master’ and ‘whitelist’.
To fix it, first find out what the project is now using, which you can find via their github, gitlab or other git server.
Then do this to capture the current configuration:
$ git branch -vv
...
* master 968695b [origin/master] Track which contest a ballot was sampled for (#629)
...
Find the line describing the master branch, and note whether the remote repo is called origin, upstream or whatever.
Then using that information, change the branch name to the new one, e.g. if it says you're currently tracking origin/master, substitute main:
git branch master --set-upstream-to origin/main
You can also rename your own branch to avoid future confusion:
git branch -m main
Round up to Second Decimal Place in Python
Here is a more general one-liner that works for any digits:
import math
def ceil(number, digits) -> float: return math.ceil((10.0 ** digits) * number) / (10.0 ** digits)
Example usage:
>>> ceil(1.111111, 2)
1.12
Caveat: as stated by nimeshkiranverma:
>>> ceil(1.11, 2)
1.12 #Because: 1.11 * 100.0 has value 111.00000000000001
How to serve up a JSON response using Go?
You can set your content-type header so clients know to expect json
w.Header().Set("Content-Type", "application/json")
Another way to marshal a struct to json is to build an encoder using the http.ResponseWriter
// get a payload p := Payload{d}
json.NewEncoder(w).Encode(p)
Asynchronously wait for Task<T> to complete with timeout
A few variants of Andrew Arnott's answer:
If you want to wait for an existing task and find out whether it completed or timed out, but don't want to cancel it if the timeout occurs:
public static async Task<bool> TimedOutAsync(this Task task, int timeoutMilliseconds) { if (timeoutMilliseconds < 0 || (timeoutMilliseconds > 0 && timeoutMilliseconds < 100)) { throw new ArgumentOutOfRangeException(); } if (timeoutMilliseconds == 0) { return !task.IsCompleted; // timed out if not completed } var cts = new CancellationTokenSource(); if (await Task.WhenAny( task, Task.Delay(timeoutMilliseconds, cts.Token)) == task) { cts.Cancel(); // task completed, get rid of timer await task; // test for exceptions or task cancellation return false; // did not timeout } else { return true; // did timeout } }If you want to start a work task and cancel the work if the timeout occurs:
public static async Task<T> CancelAfterAsync<T>( this Func<CancellationToken,Task<T>> actionAsync, int timeoutMilliseconds) { if (timeoutMilliseconds < 0 || (timeoutMilliseconds > 0 && timeoutMilliseconds < 100)) { throw new ArgumentOutOfRangeException(); } var taskCts = new CancellationTokenSource(); var timerCts = new CancellationTokenSource(); Task<T> task = actionAsync(taskCts.Token); if (await Task.WhenAny(task, Task.Delay(timeoutMilliseconds, timerCts.Token)) == task) { timerCts.Cancel(); // task completed, get rid of timer } else { taskCts.Cancel(); // timer completed, get rid of task } return await task; // test for exceptions or task cancellation }If you have a task already created that you want to cancel if a timeout occurs:
public static async Task<T> CancelAfterAsync<T>(this Task<T> task, int timeoutMilliseconds, CancellationTokenSource taskCts) { if (timeoutMilliseconds < 0 || (timeoutMilliseconds > 0 && timeoutMilliseconds < 100)) { throw new ArgumentOutOfRangeException(); } var timerCts = new CancellationTokenSource(); if (await Task.WhenAny(task, Task.Delay(timeoutMilliseconds, timerCts.Token)) == task) { timerCts.Cancel(); // task completed, get rid of timer } else { taskCts.Cancel(); // timer completed, get rid of task } return await task; // test for exceptions or task cancellation }
Another comment, these versions will cancel the timer if the timeout does not occur, so multiple calls will not cause timers to pile up.
sjb
Getting Error 800a0e7a "Provider cannot be found. It may not be properly installed."
Have you got the driver installed? If you go into Start > Settings > Control Panel > Administrative Tools and click the Data Sources, then select the Drivers tab your driver info should be registered there.
Failing that it may be easier to simply set up a DSN connection to test with.
You can define multiple connection strings of course and set-up a 'mode' for working on different machines.
Also there's ConnectionStrings.com.
-- EDIT --
Just to further this, I found this thread on another site.
Twitter Bootstrap - borders
If you look at Twitter's own container-app.html demo on GitHub, you'll get some ideas on using borders with their grid.
For example, here's the extracted part of the building blocks to their 940-pixel wide 16-column grid system:
.row {
zoom: 1;
margin-left: -20px;
}
.row > [class*="span"] {
display: inline;
float: left;
margin-left: 20px;
}
.span4 {
width: 220px;
}
To allow for borders on specific elements, they added embedded CSS to the page that reduces matching classes by enough amount to account for the border(s).
For example, to allow for the left border on the sidebar, they added this CSS in the <head> after the the main <link href="../bootstrap.css" rel="stylesheet">.
.content .span4 {
margin-left: 0;
padding-left: 19px;
border-left: 1px solid #eee;
}
You'll see they've reduced padding-left by 1px to allow for the addition of the new left border. Since this rule appears later in the source order, it overrides any previous or external declarations.
I'd argue this isn't exactly the most robust or elegant approach, but it illustrates the most basic example.
How to make an executable JAR file?
Here it is in one line:
jar cvfe myjar.jar package.MainClass *.class
where MainClass is the class with your main method, and package is MainClass's package.
Note you have to compile your .java files to .class files before doing this.
c create new archive
v generate verbose output on standard output
f specify archive file name
e specify application entry point for stand-alone application bundled into an executable jar file
This answer inspired by Powerslave's comment on another answer.
How to fix curl: (60) SSL certificate: Invalid certificate chain
In some systems like your office system, there is sometimes a firewall/security client that is installed for security purpose. Try uninstalling that and then run the command again, it should start the download.
My system had Netskope Client installed and was blocking the ssl communication.
Search in finder -> uninstall netskope, run it, and try installing homebrew:
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"
PS: consider installing the security client.
Configuring Hibernate logging using Log4j XML config file?
In response to homaxto's comment, this is what I have right now.
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
<appender name="console" class="org.apache.log4j.ConsoleAppender">
<param name="Threshold" value="debug"/>
<param name="Target" value="System.out"/>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{ABSOLUTE} [%t] %-5p %c{1} - %m%n"/>
</layout>
</appender>
<appender name="rolling-file" class="org.apache.log4j.RollingFileAppender">
<param name="file" value="Program-Name.log"/>
<param name="MaxFileSize" value="500KB"/>
<param name="MaxBackupIndex" value="4"/>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d [%t] %-5p %l - %m%n"/>
</layout>
</appender>
<logger name="org.hibernate">
<level value="info" />
</logger>
<root>
<priority value ="debug" />
<appender-ref ref="console" />
<appender-ref ref="rolling-file" />
</root>
</log4j:configuration>
The key part being
<logger name="org.hibernate">
<level value="info" />
</logger>
Hope this helps.
python JSON object must be str, bytes or bytearray, not 'dict
json.dumps() is used to decode JSON data
import json
# initialize different data
str_data = 'normal string'
int_data = 1
float_data = 1.50
list_data = [str_data, int_data, float_data]
nested_list = [int_data, float_data, list_data]
dictionary = {
'int': int_data,
'str': str_data,
'float': float_data,
'list': list_data,
'nested list': nested_list
}
# convert them to JSON data and then print it
print('String :', json.dumps(str_data))
print('Integer :', json.dumps(int_data))
print('Float :', json.dumps(float_data))
print('List :', json.dumps(list_data))
print('Nested List :', json.dumps(nested_list, indent=4))
print('Dictionary :', json.dumps(dictionary, indent=4)) # the json data will be indented
output:
String : "normal string"
Integer : 1
Float : 1.5
List : ["normal string", 1, 1.5]
Nested List : [
1,
1.5,
[
"normal string",
1,
1.5
]
]
Dictionary : {
"int": 1,
"str": "normal string",
"float": 1.5,
"list": [
"normal string",
1,
1.5
],
"nested list": [
1,
1.5,
[
"normal string",
1,
1.5
]
]
}
- Python Object to JSON Data Conversion
| Python | JSON |
|:--------------------------------------:|:------:|
| dict | object |
| list, tuple | array |
| str | string |
| int, float, int- & float-derived Enums | number |
| True | true |
| False | false |
| None | null |
json.loads() is used to convert JSON data into Python data.
import json
# initialize different JSON data
arrayJson = '[1, 1.5, ["normal string", 1, 1.5]]'
objectJson = '{"a":1, "b":1.5 , "c":["normal string", 1, 1.5]}'
# convert them to Python Data
list_data = json.loads(arrayJson)
dictionary = json.loads(objectJson)
print('arrayJson to list_data :\n', list_data)
print('\nAccessing the list data :')
print('list_data[2:] =', list_data[2:])
print('list_data[:1] =', list_data[:1])
print('\nobjectJson to dictionary :\n', dictionary)
print('\nAccessing the dictionary :')
print('dictionary[\'a\'] =', dictionary['a'])
print('dictionary[\'c\'] =', dictionary['c'])
output:
arrayJson to list_data :
[1, 1.5, ['normal string', 1, 1.5]]
Accessing the list data :
list_data[2:] = [['normal string', 1, 1.5]]
list_data[:1] = [1]
objectJson to dictionary :
{'a': 1, 'b': 1.5, 'c': ['normal string', 1, 1.5]}
Accessing the dictionary :
dictionary['a'] = 1
dictionary['c'] = ['normal string', 1, 1.5]
- JSON Data to Python Object Conversion
| JSON | Python |
|:-------------:|:------:|
| object | dict |
| array | list |
| string | str |
| number (int) | int |
| number (real) | float |
| true | True |
| false | False |
Does a finally block always get executed in Java?
Example code:
public static void main(String[] args) {
System.out.println(Test.test());
}
public static int test() {
try {
return 0;
}
finally {
System.out.println("finally trumps return.");
}
}
Output:
finally trumps return.
0
Find when a file was deleted in Git
Short answer:
git log --full-history -- your_file
will show you all commits in your repo's history, including merge commits, that touched your_file. The last (top) one is the one that deleted the file.
Some explanation:
The --full-history flag here is important. Without it, Git performs "history simplification" when you ask it for the log of a file. The docs are light on details about exactly how this works and I lack the grit and courage required to try to figure it out from the source code, but the git-log docs have this much to say:
Default mode
Simplifies the history to the simplest history explaining the final state of the tree. Simplest because it prunes some side branches if the end result is the same (i.e. merging branches with the same content)
This is obviously concerning when the file whose history we want is deleted, since the simplest history explaining the final state of a deleted file is no history. Is there a risk that git log without --full-history will simply claim that the file was never created? Unfortunately, yes. Here's a demonstration:
mark@lunchbox:~/example$ git init
Initialised empty Git repository in /home/mark/example/.git/
mark@lunchbox:~/example$ touch foo && git add foo && git commit -m "Added foo"
[master (root-commit) ddff7a7] Added foo
1 file changed, 0 insertions(+), 0 deletions(-)
create mode 100644 foo
mark@lunchbox:~/example$ git checkout -b newbranch
Switched to a new branch 'newbranch'
mark@lunchbox:~/example$ touch bar && git add bar && git commit -m "Added bar"
[newbranch 7f9299a] Added bar
1 file changed, 0 insertions(+), 0 deletions(-)
create mode 100644 bar
mark@lunchbox:~/example$ git checkout master
Switched to branch 'master'
mark@lunchbox:~/example$ git rm foo && git commit -m "Deleted foo"
rm 'foo'
[master 7740344] Deleted foo
1 file changed, 0 insertions(+), 0 deletions(-)
delete mode 100644 foo
mark@lunchbox:~/example$ git checkout newbranch
Switched to branch 'newbranch'
mark@lunchbox:~/example$ git rm bar && git commit -m "Deleted bar"
rm 'bar'
[newbranch 873ed35] Deleted bar
1 file changed, 0 insertions(+), 0 deletions(-)
delete mode 100644 bar
mark@lunchbox:~/example$ git checkout master
Switched to branch 'master'
mark@lunchbox:~/example$ git merge newbranch
Already up-to-date!
Merge made by the 'recursive' strategy.
mark@lunchbox:~/example$ git log -- foo
commit 77403443a13a93073289f95a782307b1ebc21162
Author: Mark Amery
Date: Tue Jan 12 22:50:50 2016 +0000
Deleted foo
commit ddff7a78068aefb7a4d19c82e718099cf57be694
Author: Mark Amery
Date: Tue Jan 12 22:50:19 2016 +0000
Added foo
mark@lunchbox:~/example$ git log -- bar
mark@lunchbox:~/example$ git log --full-history -- foo
commit 2463e56a21e8ee529a59b63f2c6fcc9914a2b37c
Merge: 7740344 873ed35
Author: Mark Amery
Date: Tue Jan 12 22:51:36 2016 +0000
Merge branch 'newbranch'
commit 77403443a13a93073289f95a782307b1ebc21162
Author: Mark Amery
Date: Tue Jan 12 22:50:50 2016 +0000
Deleted foo
commit ddff7a78068aefb7a4d19c82e718099cf57be694
Author: Mark Amery
Date: Tue Jan 12 22:50:19 2016 +0000
Added foo
mark@lunchbox:~/example$ git log --full-history -- bar
commit 873ed352c5e0f296b26d1582b3b0b2d99e40d37c
Author: Mark Amery
Date: Tue Jan 12 22:51:29 2016 +0000
Deleted bar
commit 7f9299a80cc9114bf9f415e1e9a849f5d02f94ec
Author: Mark Amery
Date: Tue Jan 12 22:50:38 2016 +0000
Added bar
Notice how git log -- bar in the terminal dump above resulted in literally no output; Git is "simplifying" history down into a fiction where bar never existed. git log --full-history -- bar, on the other hand, gives us the commit that created bar and the commit that deleted it.
To be clear: this issue isn't merely theoretical. I only looked into the docs and discovered the --full-history flag because git log -- some_file was failing for me in a real repository where I was trying to track a deleted file down. History simplification might sometimes be helpful when you're trying to understand how a currently-existing file came to be in its current state, but when trying to track down a file deletion it's more likely to screw you over by hiding the commit you care about. Always use the --full-history flag for this use case.
What is a None value?
largest=none
smallest =none
While True :
num =raw_input ('enter a number ')
if num =="done ": break
try :
inp =int (inp)
except:
Print'Invalid input'
if largest is none :
largest=inp
elif inp>largest:
largest =none
print 'maximum', largest
if smallest is none:
smallest =none
elif inp<smallest :
smallest =inp
print 'minimum', smallest
print 'maximum, minimum, largest, smallest
JavaScript null check
In JavaScript, null is a special singleton object which is helpful for signaling "no value". You can test for it by comparison and, as usual in JavaScript, it's a good practice to use the === operator to avoid confusing type coercion:
var a = null;
alert(a === null); // true
As @rynah mentions, "undefined" is a bit confusing in JavaScript. However, it's always safe to test if the typeof(x) is the string "undefined", even if "x" is not a declared variable:
alert(typeof(x) === 'undefined'); // true
Also, variables can have the "undefined value" if they are not initialized:
var y;
alert(typeof(y) === 'undefined'); // true
Putting it all together, your check should look like this:
if ((typeof(data) !== 'undefined') && (data !== null)) {
// ...
However, since the variable "data" is always defined since it is a formal function parameter, using the "typeof" operator is unnecessary and you can safely compare directly with the "undefined value".
function(data) {
if ((data !== undefined) && (data !== null)) {
// ...
This snippet amounts to saying "if the function was called with an argument which is defined and is not null..."
jQuery: click function exclude children.
Or you can do also:
$('.example').on('click', function(e) {
if( e.target != this )
return false;
// ... //
});
ZIP file content type for HTTP request
If you want the MIME type for a file, you can use the following code:
- (NSString *)mimeTypeForPath:(NSString *)path
{
// get a mime type for an extension using MobileCoreServices.framework
CFStringRef extension = (__bridge CFStringRef)[path pathExtension];
CFStringRef UTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, extension, NULL);
assert(UTI != NULL);
NSString *mimetype = CFBridgingRelease(UTTypeCopyPreferredTagWithClass(UTI, kUTTagClassMIMEType));
assert(mimetype != NULL);
CFRelease(UTI);
return mimetype;
}
In the case of a ZIP file, this will return application/zip.
Authenticate with GitHub using a token
To avoid handing over "the keys to the castle"...
Note that sigmavirus24's response requires you to give Travis a token with fairly wide permissions -- since GitHub only offers tokens with wide scopes like "write all my public repos" or "write all my private repos".
If you want to tighten down access (with a bit more work!) you can use GitHub deployment keys combined with Travis encrypted yaml fields.
Here's a sketch of how the technique works...
First generate an RSA deploy key (via ssh-keygen) called my_key and add it as a deploy key in your github repo settings.
Then...
$ password=`openssl rand -hex 32`
$ cat my_key | openssl aes-256-cbc -k "$password" -a > my_key.enc
$ travis encrypt --add password=$password -r my-github-user/my-repo
Then use the $password file to decrypt your deploy key at integration-time, by adding to your yaml file:
before_script:
- openssl aes-256-cbc -k "$password" -d -a -in my_key.enc -out my_deploy_key
- echo -e "Host github.com\n IdentityFile /path/to/my_deploy_key" > ~/.ssh/config
- echo "github.com ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ==" > ~/.ssh/known_hosts
Note: the last line pre-populates github's RSA key, which avoids the need for manually accepting at the time of a connection.
continuing execution after an exception is thrown in java
Try this:
try
{
throw new InvalidEmployeeTypeException();
input.nextLine();
}
catch(InvalidEmployeeTypeException ex)
{
//do error handling
}
continue;
Efficient evaluation of a function at every cell of a NumPy array
A similar question is: Mapping a NumPy array in place. If you can find a ufunc for your f(), then you should use the out parameter.
How to insert a line break before an element using CSS
Yes, totally doable but it is definitely a total hack (people may give you dirty looks for writing such code).
Here is the HTML:
<div>lorem ipdum dolor sit <span id="restart">amit e pluribus unum</span></div>
Here is the CSS:
#restart:before { content: 'hiddentext'; font-size:0; display:block; line-height:0; }
Here is the fiddle: http://jsfiddle.net/AprNY/
How to install a Notepad++ plugin offline?
The solution for me is:
- Put the plugin inside /plugin folder (for me it's XMLTools.dll, with some additional files that is instructed to be placed in the installdir)
- "Run as administrator" on notepad++.exe
- Settings>Import>Import plugin(s)..., browse to intended .dll, select it
- Prompt comes up telling me to restart
- Done!
Append text using StreamWriter
Also look at log4net, which makes logging to 1 or more event stores — whether it's the console, the Windows event log, a text file, a network pipe, a SQL database, etc. — pretty trivial. You can even filter stuff in its configuration, for instance, so that only log records of a particular severity (say ERROR or FATAL) from a single component or assembly are directed to a particular event store.
How do you list the primary key of a SQL Server table?
If Primary Key and type needed, this query may be useful:
SELECT L.TABLE_SCHEMA, L.TABLE_NAME, L.COLUMN_NAME, R.TypeName
FROM(
SELECT COLUMN_NAME, TABLE_NAME, TABLE_SCHEMA
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE OBJECTPROPERTY(OBJECT_ID(CONSTRAINT_SCHEMA + '.' + QUOTENAME(CONSTRAINT_NAME)), 'IsPrimaryKey') = 1
)L
LEFT JOIN (
SELECT
OBJECT_NAME(c.OBJECT_ID) TableName ,c.name AS ColumnName ,t.name AS TypeName
FROM sys.columns AS c
JOIN sys.types AS t ON c.user_type_id=t.user_type_id
)R ON L.COLUMN_NAME = R.ColumnName AND L.TABLE_NAME = R.TableName
Clean out Eclipse workspace metadata
In some cases, I could prevent Eclipse from crashing during startup by deleting a .snap file in your workspace meta-data (.metadata/.plugins/org.eclipse.core.resources/.snap).
See also https://bugs.eclipse.org/bugs/show_bug.cgi?id=149121 (the bug has been closed, but happened to me recently)
PHP isset() with multiple parameters
Use the php's OR (||) logical operator for php isset() with multiple operator
e.g
if (isset($_POST['room']) || ($_POST['cottage']) || ($_POST['villa'])) {
}
How to save and extract session data in codeigniter
initialize the Session class in the constructor of controller using
$this->load->library('session');
for example :
function __construct()
{
parent::__construct();
$this->load->model('user','',TRUE);
$this->load->model('user_activity','',TRUE);
$this->load->library('session');
}
How do you get current active/default Environment profile programmatically in Spring?
You can autowire the Environment
@Autowired
Environment env;
Environment offers:
Switch statement with returns -- code correctness
Remove them. It's idiomatic to return from case statements, and it's "unreachable code" noise otherwise.
Is there a list of Pytz Timezones?
You can list all the available timezones with pytz.all_timezones:
In [40]: import pytz
In [41]: pytz.all_timezones
Out[42]:
['Africa/Abidjan',
'Africa/Accra',
'Africa/Addis_Ababa',
...]
There is also pytz.common_timezones:
In [45]: len(pytz.common_timezones)
Out[45]: 403
In [46]: len(pytz.all_timezones)
Out[46]: 563
How do I split an int into its digits?
the classic trick is to use modulo 10: x%10 gives you the first digit(ie the units digit). For others, you'll need to divide first(as shown by many other posts already)
Here's a little function to get all the digits into a vector(which is what you seem to want to do):
using namespace std;
vector<int> digits(int x){
vector<int> returnValue;
while(x>=10){
returnValue.push_back(x%10);//take digit
x=x/10; //or x/=10 if you like brevity
}
//don't forget the last digit!
returnValue.push_back(x);
return returnValue;
}
Copy to Clipboard for all Browsers using javascript
I spent a lot of time looking for a solution to this problem too. Here's what i've found thus far:
If you want your users to be able to click on a button and copy some text, you may have to use Flash.
If you want your users to press Ctrl+C anywhere on the page, but always copy xyz to the clipboard, I wrote an all-JS solution in YUI3 (although it could easily be ported to other frameworks, or raw JS if you're feeling particularly self-loathing).
It involves creating a textbox off the screen which gets highlighted as soon as the user hits Ctrl/CMD. When they hit 'C' shortly after, they copy the hidden text. If they hit 'V', they get redirected to a container (of your choice) before the paste event fires.
This method can work well, because while you listen for the Ctrl/CMD keydown anywhere in the body, the 'A', 'C' or 'V' keydown listeners only attach to the hidden text box (and not the whole body). It also doesn't have to break the users expectations - you only get redirected to the hidden box if you had nothing selected to copy anyway!
Here's what i've got working on my site, but check http://at.cg/js/clipboard.js for updates if there are any:
YUI.add('clipboard', function(Y) {
// Change this to the id of the text area you would like to always paste in to:
pasteBox = Y.one('#pasteDIV');
// Make a hidden textbox somewhere off the page.
Y.one('body').append('<input id="copyBox" type="text" name="result" style="position:fixed; top:-20%;" onkeyup="pasteBox.focus()">');
copyBox = Y.one('#copyBox');
// Key bindings for Ctrl+A, Ctrl+C, Ctrl+V, etc:
// Catch Ctrl/Window/Apple keydown anywhere on the page.
Y.on('key', function(e) {
copyData();
// Uncomment below alert and remove keyCodes after 'down:' to figure out keyCodes for other buttons.
// alert(e.keyCode);
// }, 'body', 'down:', Y);
}, 'body', 'down:91,224,17', Y);
// Catch V - BUT ONLY WHEN PRESSED IN THE copyBox!!!
Y.on('key', function(e) {
// Oh no! The user wants to paste, but their about to paste into the hidden #copyBox!!
// Luckily, pastes happen on keyPress (which is why if you hold down the V you get lots of pastes), and we caught the V on keyDown (before keyPress).
// Thus, if we're quick, we can redirect the user to the right box and they can unload their paste into the appropriate container. phew.
pasteBox.select();
}, '#copyBox', 'down:86', Y);
// Catch A - BUT ONLY WHEN PRESSED IN THE copyBox!!!
Y.on('key', function(e) {
// User wants to select all - but he/she is in the hidden #copyBox! That wont do.. select the pasteBox instead (which is probably where they wanted to be).
pasteBox.select();
}, '#copyBox', 'down:65', Y);
// What to do when keybindings are fired:
// User has pressed Ctrl/Meta, and is probably about to press A,C or V. If they've got nothing selected, or have selected what you want them to copy, redirect to the hidden copyBox!
function copyData() {
var txt = '';
// props to Sabarinathan Arthanari for sharing with the world how to get the selected text on a page, cheers mate!
if (window.getSelection) { txt = window.getSelection(); }
else if (document.getSelection) { txt = document.getSelection(); }
else if (document.selection) { txt = document.selection.createRange().text; }
else alert('Something went wrong and I have no idea why - please contact me with your browser type (Firefox, Safari, etc) and what you tried to copy and I will fix this immediately!');
// If the user has nothing selected after pressing Ctrl/Meta, they might want to copy what you want them to copy.
if(txt=='') {
copyBox.select();
}
// They also might have manually selected what you wanted them to copy! How unnecessary! Maybe now is the time to tell them how silly they are..?!
else if (txt == copyBox.get('value')) {
alert('This site uses advanced copy/paste technology, possibly from the future.\n \nYou do not need to select things manually - just press Ctrl+C! \n \n(Ctrl+V will always paste to the main box too.)');
copyBox.select();
} else {
// They also might have selected something completely different! If so, let them. It's only fair.
}
}
});
Hope someone else finds this useful :]
Can jQuery check whether input content has changed?
Yes, compare it to the value it was before it changed.
var previousValue = $("#elm").val();
$("#elm").keyup(function(e) {
var currentValue = $(this).val();
if(currentValue != previousValue) {
previousValue = currentValue;
alert("Value changed!");
}
});
Another option is to only trigger your changed function on certain keys. Use e.KeyCode to figure out what key was pressed.
What is the best way to create a string array in python?
strlist =[{}]*10
strlist[0] = set()
strlist[0].add("Beef")
strlist[0].add("Fish")
strlist[1] = {"Apple", "Banana"}
strlist[1].add("Cherry")
print(strlist[0])
print(strlist[1])
print(strlist[2])
print("Array size:", len(strlist))
print(strlist)
How to reset postgres' primary key sequence when it falls out of sync?
The shortest and fastest way:
SELECT setval('tbl_tbl_id_seq', max(tbl_id)) FROM tbl;
tbl_id being the serial column of table tbl, drawing from the sequence tbl_tbl_id_seq (which is the default automatic name).
If you don't know the name of the attached sequence (which doesn't have to be in default form), use pg_get_serial_sequence():
SELECT setval(pg_get_serial_sequence('tbl', 'tbl_id'), max(tbl_id)) FROM tbl;
There is no off-by-one error here. The manual:
The two-parameter form sets the sequence's
last_valuefield to the specified value and sets itsis_calledfield to true, meaning that the nextnextvalwill advance the sequence before returning a value.
Bold emphasis mine.
If the table can be empty and to actually start from 1 in this case:
SELECT setval(pg_get_serial_sequence('tbl', 'tbl_id')
, COALESCE(max(tbl_id) + 1, 1)
, false)
FROM tbl;
We can't just use the 2-parameter form and start with 0 because the lower bound of sequences is 1 by default (unless customized).
Concurrency
To defend against concurrent sequence activity or writes to the table in the above queries, lock the table in SHARE mode. It keeps concurrent transactions from writing a higher number (or anything at all).
To also take clients into account that may have fetched sequence numbers in advance without any locks on the main table, yet (can happen in certain setups), only increase the current value of the sequence, never decrease it. It may seem paranoid, but that's in accord with the nature of sequences and defending against concurrency issues.
BEGIN;
LOCK TABLE tbl IN SHARE MODE;
SELECT setval('tbl_tbl_id_seq', max(tbl_id))
FROM tbl
HAVING max(tbl_id) > (SELECT last_value FROM tbl_tbl_id_seq); -- prevent lower number
COMMIT;
SHARE mode is strong enough for the purpose. The manual:
This mode protects a table against concurrent data changes.
It conflicts with ROW EXCLUSIVE mode.
The commands
UPDATE,DELETE, andINSERTacquire this lock mode on the target table
Regex to split a CSV
I'm late to the party, but the following is the Regular Expression I use:
(?:,"|^")(""|[\w\W]*?)(?=",|"$)|(?:,(?!")|^(?!"))([^,]*?)(?=$|,)|(\r\n|\n)
This pattern has three capturing groups:
- Contents of a quoted cell
- Contents of an unquoted cell
- A new line
This pattern handles all of the following:
- Normal cell contents without any special features: one,2,three
- Cell containing a double quote (" is escaped to ""): no quote,"a ""quoted"" thing",end
- Cell contains a newline character: one,two\nthree,four
- Normal cell contents which have an internal quote: one,two"three,four
- Cell contains quotation mark followed by comma: one,"two ""three"", four",five
If you have are using a more capable flavor of regex with named groups and lookbehinds, I prefer the following:
(?<quoted>(?<=,"|^")(?:""|[\w\W]*?)*(?=",|"$))|(?<normal>(?<=,(?!")|^(?!"))[^,]*?(?=(?<!")$|(?<!"),))|(?<eol>\r\n|\n)
Edit
(?:^"|,")(""|[\w\W]*?)(?=",|"$)|(?:^(?!")|,(?!"))([^,]*?)(?=$|,)|(\r\n|\n)
This slightly modified pattern handles lines where the first column is empty as long as you are not using Javascript. For some reason Javascript will omit the second column with this pattern. I was unable to correctly handle this edge-case.
How to convert an int to a hex string?
What about hex()?
hex(255) # 0xff
If you really want to have \ in front you can do:
print '\\' + hex(255)[1:]
LEFT JOIN in LINQ to entities?
May be I come later to answer but right now I'm facing with this... if helps there are one more solution (the way i solved it).
var query2 = (
from users in Repo.T_Benutzer
join mappings in Repo.T_Benutzer_Benutzergruppen on mappings.BEBG_BE equals users.BE_ID into tmpMapp
join groups in Repo.T_Benutzergruppen on groups.ID equals mappings.BEBG_BG into tmpGroups
from mappings in tmpMapp.DefaultIfEmpty()
from groups in tmpGroups.DefaultIfEmpty()
select new
{
UserId = users.BE_ID
,UserName = users.BE_User
,UserGroupId = mappings.BEBG_BG
,GroupName = groups.Name
}
);
By the way, I tried using the Stefan Steiger code which also helps but it was slower as hell.
How to reference static assets within vue javascript
For anyone looking to refer images from template, You can refer images directly using '@'
Example:
<img src="@/assets/images/home.png"/>
How to have multiple conditions for one if statement in python
Darian Moody has a nice solution to this challenge in his blog post:
a = 1
b = 2
c = True
rules = [a == 1,
b == 2,
c == True]
if all(rules):
print("Success!")
The all() method returns True when all elements in the given iterable are true. If not, it returns False.
You can read a little more about it in the python docs here and more information and examples here.
(I also answered the similar question with this info here - How to have multiple conditions for one if statement in python)
Is it acceptable and safe to run pip install under sudo?
Your original problem is that pip cannot write the logs to the folder.
IOError: [Errno 13] Permission denied: '/Users/markwalker/Library/Logs/pip.log'
You need to cd into a folder in which the process invoked can write like /tmp so a cd /tmp and re invoking the command will probably work but is not what you want.
BUT actually for this particular case (you not wanting to use sudo for installing python packages) and no need for global package installs you can use the --user flag like this :
pip install --user <packagename>
and it will work just fine.
I assume you have a one user python python installation and do not want to bother with reading about virtualenv (which is not very userfriendly) or pipenv.
As some people in the comments section have pointed out the next approach is not a very good idea unless you do not know what to do and got stuck:
Another approach for global packages like in your case you want to do something like :
chown -R $USER /Library/Python/2.7/site-packages/
or more generally
chown -R $USER <path to your global pip packages>
Removing all empty elements from a hash / YAML?
Deep deletion nil values from a hash.
# returns new instance of hash with deleted nil values
def self.deep_remove_nil_values(hash)
hash.each_with_object({}) do |(k, v), new_hash|
new_hash[k] = deep_remove_nil_values(v) if v.is_a?(Hash)
new_hash[k] = v unless v.nil?
end
end
# rewrite current hash
def self.deep_remove_nil_values!(hash)
hash.each do |k, v|
deep_remove_nil_values(v) if v.is_a?(Hash)
hash.delete(k) if v.nil?
end
end
How to print like printf in Python3?
Other words printf absent in python... I'm surprised! Best code is
def printf(format, *args):
sys.stdout.write(format % args)
Because of this form allows not to print \n. All others no. That's why print is bad operator. And also you need write args in special form. There is no disadvantages in function above. It's a standard usual form of printf function.
How to start rails server?
For the latest version of Rails (Rails 5.1.4 released September 7, 2017), you need to start Rails server like below:
hello_world_rails_project$ ./bin/rails server
=> Booting Puma
=> Rails 5.1.4 application starting in development
=> Run `rails server -h` for more startup options
Puma starting in single mode...
* Version 3.10.0 (ruby 2.4.2-p198), codename: Russell's Teapot
* Min threads: 5, max threads: 5
* Environment: development
* Listening on tcp://0.0.0.0:3000
More help information:
hello_world_rails_project$ ./bin/rails --help
The most common rails commands are:
generate Generate new code (short-cut alias: "g")
console Start the Rails console (short-cut alias: "c")
server Start the Rails server (short-cut alias: "s")
test Run tests except system tests (short-cut alias: "t")
test:system Run system tests
dbconsole Start a console for the database specified in
config/database.yml
(short-cut alias: "db")
new Create a new Rails application. "rails new my_app" creates a
new application called MyApp in "./my_app"
Difference between long and int data types
The guarantees the standard gives you go like this:
1 == sizeof(char) <= sizeof(short) <= sizeof (int) <= sizeof(long) <= sizeof(long long)
So it's perfectly valid for sizeof (int) and sizeof (long) to be equal, and many platforms choose to go with this approach. You will find some platforms where int is 32 bits, long is 64 bits, and long long is 128 bits, but it seems very common for sizeof (long) to be 4.
(Note that long long is recognized in C from C99 onwards, but was normally implemented as an extension in C++ prior to C++11.)
how to draw directed graphs using networkx in python?
You need to use a directed graph instead of a graph, i.e.
G = nx.DiGraph()
Then, create a list of the edge colors you want to use and pass those to nx.draw (as shown by @Marius).
Putting this all together, I get the image below. Still not quite the other picture you show (I don't know where your edge weights are coming from), but much closer! If you want more control of how your output graph looks (e.g. get arrowheads that look like arrows), I'd check out NetworkX with Graphviz.
How do I get out of 'screen' without typing 'exit'?
Ctrl + A and then Ctrl+D. Doing this will detach you from the
screensession which you can later resume by doingscreen -r.You can also do: Ctrl+A then type :. This will put you in screen command mode. Type the command
detachto be detached from the running screen session.
How do I change the ID of a HTML element with JavaScript?
It does work in Firefox (including 2.0.0.20). See http://jsbin.com/akili (add /edit to the url to edit):
<p id="one">One</p>
<a href="#" onclick="document.getElementById('one').id = 'two'; return false">Link2</a>
The first click changes the id to "two", the second click errors because the element with id="one" now can't be found!
Perhaps you have another element already with id="two" (FYI you can't have more than one element with the same id).
android - setting LayoutParams programmatically
int dp1 = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 1,
context.getResources().getDisplayMetrics());
tv.setLayoutParams(new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
dp1 * 100)); // if you want to set layout height to 100dp
llview.addView(tv);
li:before{ content: "¦"; } How to Encode this Special Character as a Bullit in an Email Stationery?
Never faced this problem before (not worked much on email, I avoid it like the plague) but you could try declaring the bullet with the unicode code point (different notation for CSS than for HTML): content: '\2022'. (you need to use the hex number, not the 8226 decimal one)
Then, in case you use something that picks up those characters and HTML-encodes them into entities (which won't work for CSS strings), I guess it will ignore that.
first-child and last-child with IE8
If you want to carry on using CSS3 selectors but need to support older browsers I would suggest using a polyfill such as Selectivizr.js
Hashmap does not work with int, char
Generics can be defined using Wrapper classes only. If you don't want to define using Wrapper types, you may use the Raw definition as below
@SuppressWarnings("rawtypes")
public HashMap buildMap(String letters)
{
HashMap checkSum = new HashMap();
for ( int i = 0; i < letters.length(); ++i )
{
checkSum.put(letters.charAt(i), primes[i]);
}
return checkSum;
}
Or define the HashMap using wrapper types, and store the primitive types. The primitive values will be promoted to their wrapper types.
public HashMap<Character, Integer> buildMap(String letters)
{
HashMap<Character, Integer> checkSum = new HashMap<Character, Integer>();
for ( int i = 0; i < letters.length(); ++i )
{
checkSum.put(letters.charAt(i), primes[i]);
}
return checkSum;
}
How to save a data frame as CSV to a user selected location using tcltk
You need not to use even the package "tcltk". You can simply do as shown below:
write.csv(x, file = "c:\\myname\\yourfile.csv", row.names = FALSE)
Give your path inspite of "c:\myname\yourfile.csv".
How can I initialize an ArrayList with all zeroes in Java?
The integer passed to the constructor represents its initial capacity, i.e., the number of elements it can hold before it needs to resize its internal array (and has nothing to do with the initial number of elements in the list).
To initialize an list with 60 zeros you do:
List<Integer> list = new ArrayList<Integer>(Collections.nCopies(60, 0));
If you want to create a list with 60 different objects, you could use the Stream API with a Supplier as follows:
List<Person> persons = Stream.generate(Person::new)
.limit(60)
.collect(Collectors.toList());
How to pause / sleep thread or process in Android?
In addition to Mr. Yankowsky's answers, you could also use postDelayed(). This is available on any View (e.g., your card) and takes a Runnable and a delay period. It executes the Runnable after that delay.
gnuplot plotting multiple line graphs
andyras is completely correct. One minor addition, try this (for example)
plot 'ls.dat' using 4:xtic(1)
This will keep your datafile in the correct order, but also preserve your version tic labels on the x-axis.
Spark RDD to DataFrame python
See,
There are two ways to convert an RDD to DF in Spark.
toDF() and createDataFrame(rdd, schema)
I will show you how you can do that dynamically.
toDF()
The toDF() command gives you the way to convert an RDD[Row] to a Dataframe. The point is, the object Row() can receive a **kwargs argument. So, there is an easy way to do that.
from pyspark.sql.types import Row
#here you are going to create a function
def f(x):
d = {}
for i in range(len(x)):
d[str(i)] = x[i]
return d
#Now populate that
df = rdd.map(lambda x: Row(**f(x))).toDF()
This way you are going to be able to create a dataframe dynamically.
createDataFrame(rdd, schema)
Other way to do that is creating a dynamic schema. How?
This way:
from pyspark.sql.types import StructType
from pyspark.sql.types import StructField
from pyspark.sql.types import StringType
schema = StructType([StructField(str(i), StringType(), True) for i in range(32)])
df = sqlContext.createDataFrame(rdd, schema)
This second way is cleaner to do that...
So this is how you can create dataframes dynamically.
Close Form Button Event
Apply the below code where you want to make code to exit application.
System.Windows.Forms.Application.Exit( )
Can .NET load and parse a properties file equivalent to Java Properties class?
No there is not : But I have created one easy class to help :
public class PropertiesUtility
{
private static Hashtable ht = new Hashtable();
public void loadProperties(string path)
{
string[] lines = System.IO.File.ReadAllLines(path);
bool readFlag = false;
foreach (string line in lines)
{
string text = Regex.Replace(line, @"\s+", "");
readFlag = checkSyntax(text);
if (readFlag)
{
string[] splitText = text.Split('=');
ht.Add(splitText[0].ToLower(), splitText[1]);
}
}
}
private bool checkSyntax(string line)
{
if (String.IsNullOrEmpty(line) || line[0].Equals('['))
{
return false;
}
if (line.Contains("=") && !String.IsNullOrEmpty(line.Split('=')[0]) && !String.IsNullOrEmpty(line.Split('=')[1]))
{
return true;
}
else
{
throw new Exception("Can not Parse Properties file please verify the syntax");
}
}
public string getProperty(string key)
{
if (ht.Contains(key))
{
return ht[key].ToString();
}
else
{
throw new Exception("Property:" + key + "Does not exist");
}
}
}
Hope this helps.
selectOneMenu ajax events
You could check whether the value of your selectOneMenu component belongs to the list of subjects.
Namely:
public void subjectSelectionChanged() {
// Cancel if subject is manually written
if (!subjectList.contains(aktNachricht.subject)) { return; }
// Write your code here in case the user selected (or wrote) an item of the list
// ....
}
Supposedly subjectList is a collection type, like ArrayList. Of course here your code will run in case the user writes an item of your selectOneMenu list.
How can I use JSON data to populate the options of a select box?
zeusstl is right. it works for me too.
<select class="form-control select2" id="myselect">
<option disabled="disabled" selected></option>
<option>Male</option>
<option>Female</option>
</select>
$.getJSON("mysite/json1.php", function(json){
$('#myselect').empty();
$('#myselect').append($('<option>').text("Select"));
$.each(json, function(i, obj){
$('#myselect').append($('<option>').text(obj.text).attr('value', obj.val));
});
});
No function matches the given name and argument types
Your function has a couple of smallint parameters.
But in the call, you are using numeric literals that are presumed to be type integer.
A string literal or string constant ('123') is not typed immediately. It remains type "unknown" until assigned or cast explicitly.
However, a numeric literal or numeric constant is typed immediately. Per documentation:
A numeric constant that contains neither a decimal point nor an exponent is initially presumed to be type
integerif its value fits in typeinteger(32 bits); otherwise it is presumed to be typebigintif its value fits in typebigint(64 bits); otherwise it is taken to be typenumeric. Constants that contain decimal points and/or exponents are always initially presumed to be typenumeric.
More explanation and links in this related answer:
Solution
Add explicit casts for the smallint parameters or quote them.
Demo
CREATE OR REPLACE FUNCTION f_typetest(smallint)
RETURNS bool AS 'SELECT TRUE' LANGUAGE sql;Incorrect call:
SELECT * FROM f_typetest(1);
Correct calls:
SELECT * FROM f_typetest('1');
SELECT * FROM f_typetest(smallint '1');
SELECT * FROM f_typetest(1::int2);
SELECT * FROM f_typetest('1'::int2);
db<>fiddle here
Old sqlfiddle.
ng-change not working on a text input
When you want to edit something in Angular you need to insert an ngModel in your html
try this in your sample:
<input type="text" name="abc" class="color" ng-model="myStyle.color">
You don't need to watch the change at all!
Is there an Eclipse plugin to run system shell in the Console?
In Eclipse 3.7, I found a terminal view plugin that I installed through Eclipse Marketplace. Details are as follow:
Local Terminal (Incubation) http://market.eclipsesource.com/yoxos/node/org.eclipse.tm.terminal.local.feature.group
A terminal emulation for local shells and external tools. Requires CDT Core 7.0 or later. Works on Linux, Solaris and Mac. Includes Source.
Side note, this terminal does not execute .bash_profile or .bashrc so you can do
source ~/.bash_profile
and (if this isn't sourced by `.bash_profile)
source ~/.bashrc
Update:
This is actually was base for Terminal plug-in for Eclipse fork. Quote from http://alexruiz.developerblogs.com/?p=2428
Uwe Stieber July 23, 2013 at 12:57 am
Alex, why not aiming for rejoining your work with the original TM Terminal? I’ve checked and haven’t found any bugzilla asking for missing features or pointing out bugs. There had been changes to the original Terminal control, so I’m not sure if all of your original reasons to clone it are still true.
JFrame background image
The best way to load an image is through the ImageIO API
BufferedImage img = ImageIO.read(new File("/path/to/some/image"));
There are a number of ways you can render an image to the screen.
You could use a JLabel. This is the simplest method if you don't want to modify the image in anyway...
JLabel background = new JLabel(new ImageIcon(img));
Then simply add it to your window as you see fit. If you need to add components to it, then you can simply set the label's layout manager to whatever you need and add your components.
If, however, you need something more sophisticated, need to change the image somehow or want to apply additional effects, you may need to use custom painting.
First cavert: Don't ever paint directly to a top level container (like JFrame). Top level containers aren't double buffered, so you may end up with some flashing between repaints, other objects live on the window, so changing it's paint process is troublesome and can cause other issues and frames have borders which are rendered inside the viewable area of the window...
Instead, create a custom component, extending from something like JPanel. Override it's paintComponent method and render your output to it, for example...
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(img, 0, 0, this);
}
Take a look at Performing Custom Painting and 2D Graphics for more details
Running code after Spring Boot starts
The "Spring Boot" way is to use a CommandLineRunner. Just add beans of that type and you are good to go. In Spring 4.1 (Boot 1.2) there is also a SmartInitializingBean which gets a callback after everything has initialized. And there is SmartLifecycle (from Spring 3).
Best way to convert pdf files to tiff files
Disclaimer: work for product I am recommending
Atalasoft has a .NET library that can convert PDF to TIFF -- we are a partner of FOXIT, so the PDF rendering is very good.
How do I initialize the base (super) class?
Both
SuperClass.__init__(self, x)
or
super(SubClass,self).__init__( x )
will work (I prefer the 2nd one, as it adheres more to the DRY principle).
See here: http://docs.python.org/reference/datamodel.html#basic-customization
How to pass macro definition from "make" command line arguments (-D) to C source code?
Call make command this way:
make CFLAGS=-Dvar=42
And be sure to use $(CFLAGS) in your compile command in the Makefile. As @jørgensen mentioned , putting the variable assignment after the make command will override the CFLAGS value already defined the Makefile.
Alternatively you could set -Dvar=42 in another variable than CFLAGS and then reuse this variable in CFLAGS to avoid completely overriding CFLAGS.
How to export dataGridView data Instantly to Excel on button click?
This line works only for the DataGridView Control on Windows Forms:
DataObject dataObj = dataGridView1.GetClipboardContent();
This one addresses the same issue, but for the DataGrid control for the WPF Framework:
private void copyDataGridContentToClipboard()
{
datagridGrupeProductie.SelectAll();
datagridGrupeProductie.ClipboardCopyMode = DataGridClipboardCopyMode.IncludeHeader;
ApplicationCommands.Copy.Execute(null, datagridGrupeProductie);
datagridGrupeProductie.UnselectAll();
}
private void rightClickGrupeProductie_Click(object sender, RoutedEventArgs e)
{
copyDataGridContentToClipboard();
Microsoft.Office.Interop.Excel.Application excelApp;
Microsoft.Office.Interop.Excel.Workbook excelWkbk;
Microsoft.Office.Interop.Excel.Worksheet excelWksht;
object misValue = System.Reflection.Missing.Value;
excelApp = new Microsoft.Office.Interop.Excel.Application();
excelApp.Visible = true;
excelWkbk = excelApp.Workbooks.Add(misValue);
excelWksht = (Microsoft.Office.Interop.Excel.Worksheet)excelWkbk.Worksheets.get_Item(1);
Microsoft.Office.Interop.Excel.Range CR = (Microsoft.Office.Interop.Excel.Range)excelWksht.Cells[1, 1];
CR.Select();
excelWksht.PasteSpecial(CR, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, true);
}
Should I use px or rem value units in my CSS?
Yes, REM and PX are relative yet other answers have suggested to go for REM over PX, I would also like to back this up using an accessibility example.
When user sets different font-size on browser, REM automatically scale up and down elements like fonts, images etc on the webpage which is not the case with PX.
In the below gif left side text is set using font size REM unit while right side font is set by PX unit.
As you can see that REM is scaling up/down automatically when I resize the default font-size of webpage.(bottom-right side)
Default font-size of a webpage is 16px which is equal to 1 rem (only for default html page i.e. html{font-size:100%}), so, 1.25rem is equal to 20px.
P.S: who else is using REM? CSS Frameworks! like Bootstrap 4, Bulma CSS etc, so better get along with it.
XDocument or XmlDocument
XmlDocument is great for developers who are familiar with the XML DOM object model. It's been around for a while, and more or less corresponds to a W3C standard. It supports manual navigation as well as XPath node selection.
XDocument powers the LINQ to XML feature in .NET 3.5. It makes heavy use of IEnumerable<> and can be easier to work with in straight C#.
Both document models require you to load the entire document into memory (unlike XmlReader for example).
Java using enum with switch statement
Short associative function example:
public String getIcon(TipoNotificacao tipo)
{
switch (tipo){
case Comentou : return "fa fa-comments";
case ConviteEnviou : return "icon-envelope";
case ConviteAceitou : return "fa fa-bolt";
default: return "";
}
}
Like @Dhanushka said, omit the qualifier inside "switch" is the key.
Flatten nested dictionaries, compressing keys
Simple function to flatten nested dictionaries. For Python 3, replace .iteritems() with .items()
def flatten_dict(init_dict):
res_dict = {}
if type(init_dict) is not dict:
return res_dict
for k, v in init_dict.iteritems():
if type(v) == dict:
res_dict.update(flatten_dict(v))
else:
res_dict[k] = v
return res_dict
The idea/requirement was: Get flat dictionaries with no keeping parent keys.
Example of usage:
dd = {'a': 3,
'b': {'c': 4, 'd': 5},
'e': {'f':
{'g': 1, 'h': 2}
},
'i': 9,
}
flatten_dict(dd)
>> {'a': 3, 'c': 4, 'd': 5, 'g': 1, 'h': 2, 'i': 9}
Keeping parent keys is simple as well.
Package Manager Console Enable-Migrations CommandNotFoundException only in a specific VS project
I reinstalled with the commmand: Install-Package EntityFramework -IncludePrerelease and the problem went away.
"OverflowError: Python int too large to convert to C long" on windows but not mac
You'll get that error once your numbers are greater than sys.maxsize:
>>> p = [sys.maxsize]
>>> preds[0] = p
>>> p = [sys.maxsize+1]
>>> preds[0] = p
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
OverflowError: Python int too large to convert to C long
You can confirm this by checking:
>>> import sys
>>> sys.maxsize
2147483647
To take numbers with larger precision, don't pass an int type which uses a bounded C integer behind the scenes. Use the default float:
>>> preds = np.zeros((1, 3))
Java generics - ArrayList initialization
The key lies in the differences between references and instances and what the reference can promise and what the instance can really do.
ArrayList<A> a = new ArrayList<A>();
Here a is a reference to an instance of a specific type - exactly an array list of As. More explicitly, a is a reference to an array list that will accept As and will produce As. new ArrayList<A>() is an instance of an array list of As, that is, an array list that will accept As and will produce As.
ArrayList<Integer> a = new ArrayList<Number>();
Here, a is a reference to exactly an array list of Integers, i.e. exactly an array list that can accept Integers and will produce Integers. It cannot point to an array list of Numbers. That array list of Numbers can not meet all the promises of ArrayList<Integer> a (i.e. an array list of Numbers may produce objects that are not Integers, even though its empty right then).
ArrayList<Number> a = new ArrayList<Integer>();
Here, declaration of a says that a will refer to exactly an array list of Numbers, that is, exactly an array list that will accept Numbers and will produce Numbers. It cannot point to an array list of Integers, because the type declaration of a says that a can accept any Number, but that array list of Integers cannot accept just any Number, it can only accept Integers.
ArrayList<? extends Object> a= new ArrayList<Object>();
Here a is a (generic) reference to a family of types rather than a reference to a specific type. It can point to any list that is member of that family. However, the trade-off for this nice flexible reference is that they cannot promise all of the functionality that it could if it were a type-specific reference (e.g. non-generic). In this case, a is a reference to an array list that will produce Objects. But, unlike a type-specific list reference, this a reference cannot accept any Object. (i.e. not every member of the family of types that a can point to can accept any Object, e.g. an array list of Integers can only accept Integers.)
ArrayList<? super Integer> a = new ArrayList<Number>();
Again, a is a reference to a family of types (rather than a single specific type). Since the wildcard uses super, this list reference can accept Integers, but it cannot produce Integers. Said another way, we know that any and every member of the family of types that a can point to can accept an Integer. However, not every member of that family can produce Integers.
PECS - Producer extends, Consumer super - This mnemonic helps you remember that using extends means the generic type can produce the specific type (but cannot accept it). Using super means the generic type can consume (accept) the specific type (but cannot produce it).
ArrayList<ArrayList<?>> a
An array list that holds references to any list that is a member of a family of array lists types.
= new ArrayList<ArrayList<?>>(); // correct
An instance of an array list that holds references to any list that is a member of a family of array lists types.
ArrayList<?> a
An reference to any array list (a member of the family of array list types).
= new ArrayList<?>()
ArrayList<?> refers to any type from a family of array list types, but you can only instantiate a specific type.
See also How can I add to List<? extends Number> data structures?
Submit button not working in Bootstrap form
- If you put
type=submitit is a Submit Button - if you put
type=buttonit is just a button, It does not submit your form inputs.
and also you don't want to use both of these
How to implement __iter__(self) for a container object (Python)
I normally would use a generator function. Each time you use a yield statement, it will add an item to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
yield 5
yield from some_list
Pre-3.3, yield from didn't exist, so you would have to do:
def __iter__(self):
yield 5
for x in some_list:
yield x
Code signing is required for product type 'Application' in SDK 'iOS5.1'
TN2250 Tech document was retired,To resolve this add IOs5.1 or 8.1 sdk field under Anyios SDK field
in code sign problem will solved
How to get the current URL within a Django template?
You can get the url without parameters by using {{request.path}} You can get the url with parameters by using {{request.get_full_path}}
Turn on torch/flash on iPhone
iWasRobbed's answer is great, except there is an AVCaptureSession running in the background all the time. On my iPhone 4s it takes about 12% CPU power according to Instrument so my app took about 1% battery in a minute. In other words if the device is prepared for AV capture it's not cheap.
Using the code below my app requires 0.187% a minute so the battery life is more than 5x longer.
This code works just fine on any device (tested on both 3GS (no flash) and 4s). Tested on 4.3 in simulator as well.
#import <AVFoundation/AVFoundation.h>
- (void) turnTorchOn:(BOOL)on {
Class captureDeviceClass = NSClassFromString(@"AVCaptureDevice");
if (captureDeviceClass != nil) {
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
if ([device hasTorch] && [device hasFlash]){
[device lockForConfiguration:nil];
if (on) {
[device setTorchMode:AVCaptureTorchModeOn];
[device setFlashMode:AVCaptureFlashModeOn];
torchIsOn = YES;
} else {
[device setTorchMode:AVCaptureTorchModeOff];
[device setFlashMode:AVCaptureFlashModeOff];
torchIsOn = NO;
}
[device unlockForConfiguration];
}
}
}
Removing specific rows from a dataframe
Here's a solution to your problem using dplyr's filter function.
Although you can pass your data frame as the first argument to any dplyr function, I've used its %>% operator, which pipes your data frame to one or more dplyr functions (just filter in this case).
Once you are somewhat familiar with dplyr, the cheat sheet is very handy.
> print(df <- data.frame(sub=rep(1:3, each=4), day=1:4))
sub day
1 1 1
2 1 2
3 1 3
4 1 4
5 2 1
6 2 2
7 2 3
8 2 4
9 3 1
10 3 2
11 3 3
12 3 4
> print(df <- df %>% filter(!((sub==1 & day==2) | (sub==3 & day==4))))
sub day
1 1 1
2 1 3
3 1 4
4 2 1
5 2 2
6 2 3
7 2 4
8 3 1
9 3 2
10 3 3
How do I find a stored procedure containing <text>?
Stored Procedure for find text in SP.. {Dinesh Baskaran} Trendy Global Systems pvt ltd
create Procedure [dbo].[TextFinder]
(@Text varchar(500),@Type varchar(2)=NULL)
AS
BEGIN
SELECT DISTINCT o.name AS ObjectName,
CASE o.xtype
WHEN 'C' THEN 'CHECK constraint '
WHEN 'D' THEN 'Default or DEFAULT constraint'
WHEN 'F' THEN 'FOREIGN KEY constraint'
WHEN 'FN' THEN 'Scalar function'
WHEN 'IF' THEN 'In-lined table-function'
WHEN 'K' THEN 'PRIMARY KEY or UNIQUE constraint'
WHEN 'L' THEN 'Log'
WHEN 'P' THEN 'Stored procedure'
WHEN 'R' THEN 'Rule'
WHEN 'RF' THEN 'Replication filter stored procedure'
WHEN 'S' THEN 'System table'
WHEN 'TF' THEN 'Table function'
WHEN 'TR' THEN 'Trigger'
WHEN 'U' THEN 'User table'
WHEN 'V' THEN 'View'
WHEN 'X' THEN 'Extended stored procedure'
ELSE o.xtype
END AS ObjectType,
ISNULL( p.Name, '[db]') AS Location
FROM syscomments c
INNER JOIN sysobjects o ON c.id=o.id
LEFT JOIN sysobjects p ON o.Parent_obj=p.id
WHERE c.text LIKE '%' + @Text + '%' and
o.xtype = case when @Type IS NULL then o.xtype else @Type end
ORDER BY Location, ObjectName
END
React-Router open Link in new tab
In React Router version 5.0.1 and above, you can use:
<Link to="route" target="_blank" onClick={(event) => {event.preventDefault(); window.open(this.makeHref("route"));}} />
how to have two headings on the same line in html
Add a span with the style="float: right" element inside the h1 element. So you can add a "goto top of the page" link, with a unicode arrow link button.
<h1 id="myAnchor">Headline Text
<span style="float: right"><a href="#top" aria-hidden="true">?</a></span>
</h1>
Ansible playbook shell output
The debug module could really use some love, but at the moment the best you can do is use this:
- hosts: all
gather_facts: no
tasks:
- shell: ps -eo pcpu,user,args | sort -r -k1 | head -n5
register: ps
- debug: var=ps.stdout_lines
It gives an output like this:
ok: [host1] => {
"ps.stdout_lines": [
"%CPU USER COMMAND",
" 1.0 root /usr/bin/python",
" 0.6 root sshd: root@notty ",
" 0.2 root java",
" 0.0 root sort -r -k1"
]
}
ok: [host2] => {
"ps.stdout_lines": [
"%CPU USER COMMAND",
" 4.0 root /usr/bin/python",
" 0.6 root sshd: root@notty ",
" 0.1 root java",
" 0.0 root sort -r -k1"
]
}
How to create a template function within a class? (C++)
The easiest way is to put the declaration and definition in the same file, but it may cause over-sized excutable file. E.g.
class Foo
{
public:
template <typename T> void some_method(T t) {//...}
}
Also, it is possible to put template definition in the separate files, i.e. to put them in .cpp and .h files. All you need to do is to explicitly include the template instantiation to the .cpp files. E.g.
// .h file
class Foo
{
public:
template <typename T> void some_method(T t);
}
// .cpp file
//...
template <typename T> void Foo::some_method(T t)
{//...}
//...
template void Foo::some_method<int>(int);
template void Foo::some_method<double>(double);
Xcode 10, Command CodeSign failed with a nonzero exit code
Fix
Remove extended file attributes in your resource files for good, not in the compiled application bundle:
Open Terminal
Change directory to the root of your source files
$ cd /Users/rjobidon/Documents/My\ Project
List all extended attributes
$ xattr -lr .
- Remove all extended attributes
$ xattr -cr .
Xcode errors
- "Command CodeSign failed with a nonzero exit code"
- "Resource fork, Finder information, or similar detritus not allowed"
Cause
Apple introduced a security hardening change, thus code signing no longer allows any file in an app bundle to have an extended attribute containing a resource fork or Finder info.
Sources
How to use *ngIf else?
In Angular 4, 5 and 6
We can simply create a template reference variable [2] and link that to the else condition inside an *ngIf directive
The possible Syntaxes [1] are:
<!-- Only If condition -->
<div *ngIf="condition">...</div>
<!-- or -->
<ng-template [ngIf]="condition"><div>...</div></ng-template>
<!-- If and else conditions -->
<div *ngIf="condition; else elseBlock">...</div>
<!-- or -->
<ng-template #elseBlock>...</ng-template>
<!-- If-then-else -->
<div *ngIf="condition; then thenBlock else elseBlock"></div>
<ng-template #thenBlock>...</ng-template>
<ng-template #elseBlock>...</ng-template>
<!-- If and else conditions (storing condition value locally) -->
<div *ngIf="condition as value; else elseBlock">{{value}}</div>
<ng-template #elseBlock>...</ng-template>
DEMO: https://stackblitz.com/edit/angular-feumnt?embed=1&file=src/app/app.component.html
Sources:
Why is my JQuery selector returning a n.fn.init[0], and what is it?
Your result object is a jQuery element, not a javascript array. The array you wish must be under .get()
As the return value is a jQuery object, which contains an array, it's very common to call .get() on the result to work with a basic array. http://api.jquery.com/map/
Scrolling to an Anchor using Transition/CSS3
Using the scroll-behavior CSS property:
(which is supported in modern browsers but not Edge):
a {
display: inline-block;
padding: 5px 7%;
text-decoration: none;
}
nav, section {
display: block;
margin: 0 auto;
text-align: center;
}
nav {
width: 350px;
padding: 5px;
}
section {
width: 350px;
height: 130px;
overflow-y: scroll;
border: 1px solid black;
font-size: 0;
scroll-behavior: smooth; /* <----- THE SECRET ---- */
}
section div{
display: flex;
align-items: center;
justify-content: center;
height: 100%;
font-size: 8vw;
}<nav>
<a href="#page-1">1</a>
<a href="#page-2">2</a>
<a href="#page-3">3</a>
</nav>
<section>
<div id="page-1">1</div>
<div id="page-2">2</div>
<div id="page-3">3</div>
</section>python: unhashable type error
File "C:\pythonwork\readthefile080410.py", line 120, in medications_minimum3
counter[row[11]]+=1
TypeError: unhashable type: 'list'
row[11] is unhashable. It's a list. That is precisely (and only) what the error message means. You might not like it, but that is the error message.
Do this
counter[tuple(row[11])]+=1
Also, simplify.
d= [ row for row in c if counter[tuple(row[11])]>=sample_cutoff ]
LaTeX Optional Arguments
All of the above show hard it can be to make a nice, flexible (or forbid an overloaded) function in LaTeX!!! (that TeX code looks like greek to me)
well, just to add my recent (albeit not as flexible) development, here's what I've recently used in my thesis doc, with
\usepackage{ifthen} % provides conditonals...
Start the command, with the "optional" command set blank by default:
\newcommand {\figHoriz} [4] [] {
I then have the macro set a temporary variable, \temp{}, differently depending on whether or not the optional argument is blank. This could be extended to any passed argument.
\ifthenelse { \equal {#1} {} } %if short caption not specified, use long caption (no slant)
{ \def\temp {\caption[#4]{\textsl{#4}}} } % if #1 == blank
{ \def\temp {\caption[#1]{\textsl{#4}}} } % else (not blank)
Then I run the macro using the \temp{} variable for the two cases. (Here it just sets the short-caption to equal the long caption if it wasn't specified by the user).
\begin{figure}[!]
\begin{center}
\includegraphics[width=350 pt]{#3}
\temp %see above for caption etc.
\label{#2}
\end{center}
\end{figure}
}
In this case I only check for the single, "optional" argument that \newcommand{} provides. If you were to set it up for, say, 3 "optional" args, you'd still have to send the 3 blank args... eg.
\MyCommand {first arg} {} {} {}
which is pretty silly, I know, but that's about as far as I'm going to go with LaTeX - it's just not that sensical once I start looking at TeX code... I do like Mr. Robertson's xparse method though, perhaps I'll try it...
Pandas: Subtracting two date columns and the result being an integer
How about:
df_test['Difference'] = (df_test['First_Date'] - df_test['Second Date']).dt.days
This will return difference as int if there are no missing values(NaT) and float if there is.
Joining 2 SQL SELECT result sets into one
Use a FULL OUTER JOIN:
select
a.col_a,
a.col_b,
b.col_c
from
(select col_a,col_bfrom tab1) a
join
(select col_a,col_cfrom tab2) b
on a.col_a= b.col_a
React component initialize state from props
you could use key value to reset state when need, pass props to state it's not a good practice , because you have uncontrolled and controlled component in one place. Data should be in one place handled
read this
https://reactjs.org/blog/2018/06/07/you-probably-dont-need-derived-state.html#recommendation-fully-uncontrolled-component-with-a-key
How to change the MySQL root account password on CentOS7?
For me work like this: 1. Stop mysql: systemctl stop mysqld
Set the mySQL environment option systemctl set-environment MYSQLD_OPTS="--skip-grant-tables"
Start mysql usig the options you just set systemctl start mysqld
Login as root mysql -u root
After login I use FLUSH PRIVILEGES; tell the server to reload the grant tables so that account-management statements work. If i don't do that i receive this error trying to update the password: "Can't find any matching row in the user table"
How to sort a dataframe by multiple column(s)
In response to a comment added in the OP for how to sort programmatically:
Using dplyr and data.table
library(dplyr)
library(data.table)
dplyr
Just use arrange_, which is the Standard Evaluation version for arrange.
df1 <- tbl_df(iris)
#using strings or formula
arrange_(df1, c('Petal.Length', 'Petal.Width'))
arrange_(df1, ~Petal.Length, ~Petal.Width)
Source: local data frame [150 x 5]
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
(dbl) (dbl) (dbl) (dbl) (fctr)
1 4.6 3.6 1.0 0.2 setosa
2 4.3 3.0 1.1 0.1 setosa
3 5.8 4.0 1.2 0.2 setosa
4 5.0 3.2 1.2 0.2 setosa
5 4.7 3.2 1.3 0.2 setosa
6 5.4 3.9 1.3 0.4 setosa
7 5.5 3.5 1.3 0.2 setosa
8 4.4 3.0 1.3 0.2 setosa
9 5.0 3.5 1.3 0.3 setosa
10 4.5 2.3 1.3 0.3 setosa
.. ... ... ... ... ...
#Or using a variable
sortBy <- c('Petal.Length', 'Petal.Width')
arrange_(df1, .dots = sortBy)
Source: local data frame [150 x 5]
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
(dbl) (dbl) (dbl) (dbl) (fctr)
1 4.6 3.6 1.0 0.2 setosa
2 4.3 3.0 1.1 0.1 setosa
3 5.8 4.0 1.2 0.2 setosa
4 5.0 3.2 1.2 0.2 setosa
5 4.7 3.2 1.3 0.2 setosa
6 5.5 3.5 1.3 0.2 setosa
7 4.4 3.0 1.3 0.2 setosa
8 4.4 3.2 1.3 0.2 setosa
9 5.0 3.5 1.3 0.3 setosa
10 4.5 2.3 1.3 0.3 setosa
.. ... ... ... ... ...
#Doing the same operation except sorting Petal.Length in descending order
sortByDesc <- c('desc(Petal.Length)', 'Petal.Width')
arrange_(df1, .dots = sortByDesc)
more info here: https://cran.r-project.org/web/packages/dplyr/vignettes/nse.html
It is better to use formula as it also captures the environment to evaluate an expression in
data.table
dt1 <- data.table(iris) #not really required, as you can work directly on your data.frame
sortBy <- c('Petal.Length', 'Petal.Width')
sortType <- c(-1, 1)
setorderv(dt1, sortBy, sortType)
dt1
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1: 7.7 2.6 6.9 2.3 virginica
2: 7.7 2.8 6.7 2.0 virginica
3: 7.7 3.8 6.7 2.2 virginica
4: 7.6 3.0 6.6 2.1 virginica
5: 7.9 3.8 6.4 2.0 virginica
---
146: 5.4 3.9 1.3 0.4 setosa
147: 5.8 4.0 1.2 0.2 setosa
148: 5.0 3.2 1.2 0.2 setosa
149: 4.3 3.0 1.1 0.1 setosa
150: 4.6 3.6 1.0 0.2 setosa
jQuery get value of select onChange
Arrow function has a different scope than function,
this.value will give undefined for an arrow function.
To fix use
$('select').on('change',(event) => {
alert( event.target.value );
});
How could I create a list in c++?
You should really use the standard List class. Unless, of course, this is a homework question, or you want to know how lists are implemented by STL.
You'll find plenty of simple tutorials via google, like this one. If you want to know how linked lists work "under the hood", try searching for C list examples/tutorials rather than C++.
How to merge 2 JSON objects from 2 files using jq?
Who knows if you still need it, but here is the solution.
Once you get to the --slurp option, it's easy!
--slurp/-s:
Instead of running the filter for each JSON object in the input,
read the entire input stream into a large array and run the filter just once.
Then the + operator will do what you want:
jq -s '.[0] + .[1]' config.json config-user.json
(Note: if you want to merge inner objects instead of just overwriting the left file ones with the right file ones, you will need to do it manually)
Could not load file or assembly 'Newtonsoft.Json, Version=9.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed' or one of its dependencies
I had a similar problem with a new ASP.NET Core application a while ago. Turns out one of the referenced libraries used a version of Newtonsoft.Json that was lower than 9.0.0.0. So I upgraded the version for that library and the problem was solved. Not sure if you'll be able to do the same here
How to change a table name using an SQL query?
In MySQL :-
RENAME TABLE `Stu Table` TO `Stu Table_10`
Commit only part of a file in Git
With TortoiseGit:
right click on the file and use
Context Menu ? Restore after commit. This will create a copy of the file as it is. Then you can edit the file, e.g. in TortoiseGitMerge and undo all the changes you don't want to commit. After saving those changes you can commit the file.
Can IntelliJ IDEA encapsulate all of the functionality of WebStorm and PHPStorm through plugins?
Definitely a great question. I've noted this also as a sub question of the choice for versions within IDEa that this link may help to address...
http://www.jetbrains.com/idea/features/editions_comparison_matrix.html
it as well potentially possesses a ground work for looking at your other IDE choices and the options they provide.
I'm thinking WebStorm is best for JavaScript and Git repo management, meaning the HTML5 CSS Cordova kinds of stacks, which is really where (I believe along with others) the future lies and energies should be focused now... but ya it depends on your needs, etc.
Anyway this tells that story too... http://www.jetbrains.com/products.html
How to fix Uncaught InvalidValueError: setPosition: not a LatLng or LatLngLiteral: in property lat: not a number?
I was having the same problem, the fact is that the input of lat and long should be String. Only then did I manage.
for example:
Controller.
ViewBag.Lat = object.Lat.ToString().Replace(",", ".");
ViewBag.Lng = object.Lng.ToString().Replace(",", ".");
View - function javascript
<script>
function initMap() {
var myLatLng = { lat: @ViewBag.Lat, lng: @ViewBag.Lng};
// Create a map object and specify the DOM element for display.
var map = new window.google.maps.Map(document.getElementById('map'),
{
center: myLatLng,
scrollwheel: false,
zoom: 16
});
// Create a marker and set its position.
var marker = new window.google.maps.Marker({
map: map,
position: myLatLng
//title: "Blue"
});
}
</script>
I convert the double value to string and do a Replace in the ',' to '.' And so everything works normally.
Using Composer's Autoload
In my opinion, Sergiy's answer should be the selected answer for the given question. I'm sharing my understanding.
I was looking to autoload my package files using composer which I have under the dir structure given below.
<web-root>
|--------src/
| |--------App/
| |
| |--------Test/
|
|---------library/
|
|---------vendor/
| |
| |---------composer/
| | |---------autoload_psr4.php
| |
| |----------autoload.php
|
|-----------composer.json
|
I'm using psr-4 autoloading specification.
Had to add below lines to the project's composer.json. I intend to place my class files inside src/App , src/Test and library directory.
"autoload": {
"psr-4": {
"OrgName\\AppType\\AppName\\": ["src/App", "src/Test", "library/"]
}
}
This is pretty much self explaining. OrgName\AppType\AppName is my intended namespace prefix. e.g for class User in src/App/Controller/Provider/User.php -
namespace OrgName\AppType\AppName\Controller\Provider; // namespace declaration
use OrgName\AppType\AppName\Controller\Provider\User; // when using the class
Also notice "src/App", "src/Test" .. are from your web-root that is where your composer.json is. Nothing to do with the vendor dir. take a look at vendor/autoload.php
Now if composer is installed properly all that is required is #composer update
After composer update my classes loaded successfully. What I observed is that composer is adding a line in vendor/composer/autoload_psr4.php
$vendorDir = dirname(dirname(__FILE__));
$baseDir = dirname($vendorDir);
return array(
'Monolog\\' => array($vendorDir . '/monolog/monolog/src/Monolog'),
'OrgName\\AppType\\AppName\\' => array($baseDir . '/src/App', $baseDir . '/src/Test', $baseDir . '/library'),
);
This is how composer maps. For psr-0 mapping is in vendor/composer/autoload_classmap.php
Meaning of = delete after function declaration
Are there any other "modifiers" (other than
= 0and= delete)?
Since it appears no one else answered this question, I should mention that there is also =default.
How do I run two commands in one line in Windows CMD?
A quote from the documentation:
- Source: Microsoft, Windows XP Professional Product Documentation, Command shell overview
- Also: An A-Z Index of Windows CMD commands
Using multiple commands and conditional processing symbols
You can run multiple commands from a single command line or script using conditional processing symbols. When you run multiple commands with conditional processing symbols, the commands to the right of the conditional processing symbol act based upon the results of the command to the left of the conditional processing symbol.
For example, you might want to run a command only if the previous command fails. Or, you might want to run a command only if the previous command is successful.
You can use the special characters listed in the following table to pass multiple commands.
& [...]
command1 & command2
Use to separate multiple commands on one command line. Cmd.exe runs the first command, and then the second command.
&& [...]
command1 && command2
Use to run the command following && only if the command preceding the symbol is successful. Cmd.exe runs the first command, and then runs the second command only if the first command completed successfully.
|| [...]
command1 || command2
Use to run the command following || only if the command preceding || fails. Cmd.exe runs the first command, and then runs the second command only if the first command did not complete successfully (receives an error code greater than zero).
( ) [...]
(command1 & command2)
Use to group or nest multiple commands.
; or ,
command1 parameter1;parameter2
Use to separate command parameters.
Only using @JsonIgnore during serialization, but not deserialization
"user": {
"firstName": "Musa",
"lastName": "Aliyev",
"email": "[email protected]",
"passwordIn": "98989898", (or encoded version in front if we not using https)
"country": "Azeribaijan",
"phone": "+994707702747"
}
@CrossOrigin(methods=RequestMethod.POST)
@RequestMapping("/public/register")
public @ResponseBody MsgKit registerNewUsert(@RequestBody User u){
root.registerUser(u);
return new MsgKit("registered");
}
@Service
@Transactional
public class RootBsn {
@Autowired UserRepository userRepo;
public void registerUser(User u) throws Exception{
u.setPassword(u.getPasswordIn());
//Generate some salt and setPassword (encoded - salt+password)
User u=userRepo.save(u);
System.out.println("Registration information saved");
}
}
@Entity
@JsonIgnoreProperties({"recordDate","modificationDate","status","createdBy","modifiedBy","salt","password"})
public class User implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String country;
@Column(name="CREATED_BY")
private String createdBy;
private String email;
@Column(name="FIRST_NAME")
private String firstName;
@Column(name="LAST_LOGIN_DATE")
private Timestamp lastLoginDate;
@Column(name="LAST_NAME")
private String lastName;
@Column(name="MODIFICATION_DATE")
private Timestamp modificationDate;
@Column(name="MODIFIED_BY")
private String modifiedBy;
private String password;
@Transient
private String passwordIn;
private String phone;
@Column(name="RECORD_DATE")
private Timestamp recordDate;
private String salt;
private String status;
@Column(name="USER_STATUS")
private String userStatus;
public User() {
}
// getters and setters
}
Using Excel VBA to export data to MS Access table
is it possible to export without looping through all records
For a range in Excel with a large number of rows you may see some performance improvement if you create an Access.Application object in Excel and then use it to import the Excel data into Access. The code below is in a VBA module in the same Excel document that contains the following test data
Option Explicit
Sub AccImport()
Dim acc As New Access.Application
acc.OpenCurrentDatabase "C:\Users\Public\Database1.accdb"
acc.DoCmd.TransferSpreadsheet _
TransferType:=acImport, _
SpreadSheetType:=acSpreadsheetTypeExcel12Xml, _
TableName:="tblExcelImport", _
Filename:=Application.ActiveWorkbook.FullName, _
HasFieldNames:=True, _
Range:="Folio_Data_original$A1:B10"
acc.CloseCurrentDatabase
acc.Quit
Set acc = Nothing
End Sub
How to open local file on Jupyter?
Are you running this on Windows or Linux? If you're on Windows,then you should be use a path like C:\\Users\\apple\\Downloads\train.csv . If you're on Linux, then you can follow the same path.
Registry key for global proxy settings for Internet Explorer 10 on Windows 8
TRY
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings
EnableAutoProxyResultCache = dword: 0
How to get the selected date of a MonthCalendar control in C#
Using SelectionRange you will get the Start and End date.
private void monthCalendar1_DateSelected(object sender, DateRangeEventArgs e)
{
var startDate = monthCalendar1.SelectionRange.Start.ToString("dd MMM yyyy");
var endDate = monthCalendar1.SelectionRange.End.ToString("dd MMM yyyy");
}
If you want to update the maximum number of days that can be selected, then set MaxSelectionCount property. The default is 7.
// Only allow 21 days to be selected at the same time.
monthCalendar1.MaxSelectionCount = 21;
How to get thread id of a pthread in linux c program?
You can use pthread_self()
The parent gets to know the thread id after the pthread_create() is executed sucessfully, but while executing the thread if we want to access the thread id we have to use the function pthread_self().
Batch file script to zip files
I know its too late but if you still wanna try
for /d %%X in (*) do (for /d %%a in (%%X) do ( "C:\Program Files\7-Zip\7z.exe" a -tzip "%%X.zip" ".\%%a\" ))
here * is the current folder. for more options try this link
Passing a callback function to another class
You have to first declare delegate's type because delegates are strongly typed:
public void MyCallbackDelegate( string str );
public void DoRequest(string request, MyCallbackDelegate callback)
{
// do stuff....
callback("asdf");
}
delete vs delete[] operators in C++
The operators delete and delete [] are used respectively to destroy the objects created with new and new[], returning to the allocated memory left available to the compiler's memory manager.
Objects created with new must necessarily be destroyed with delete, and that the arrays created with new[] should be deleted with delete[].
Python: Fetch first 10 results from a list
check this
list = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]
list[0:10]
Outputs:
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Print an integer in binary format in Java
There are already good answers posted here for this question. But, this is the way I've tried myself (and might be the easiest logic based ? modulo/divide/add):
int decimalOrBinary = 345;
StringBuilder builder = new StringBuilder();
do {
builder.append(decimalOrBinary % 2);
decimalOrBinary = decimalOrBinary / 2;
} while (decimalOrBinary > 0);
System.out.println(builder.reverse().toString()); //prints 101011001