Programs & Examples On #Couchdbkit

Couchdbkit is a Python library which provides a full featured and easy client to access and manage CouchDB.

How to call base.base.method()?

If you want to access to base class data you must use "this" keyword or you use this keyword as reference for class.

namespace thiskeyword
{
    class Program
    {
        static void Main(string[] args)
        {
            I i = new I();
            int res = i.m1();
            Console.WriteLine(res);
            Console.ReadLine();
        }
    }

    public class E
    {
        new public int x = 3;
    }

    public class F:E
    {
        new public int x = 5;
    }

    public class G:F
    {
        new public int x = 50;
    }

    public class H:G
    {
        new public int x = 20;
    }

    public class I:H
    {
        new public int x = 30;

        public int m1()
        {
           // (this as <classname >) will use for accessing data to base class

            int z = (this as I).x + base.x + (this as G).x + (this as F).x + (this as E).x; // base.x refer to H
            return z;
        }
    }
}

How to subtract 30 days from the current date using SQL Server

TRY THIS:

Cast your VARCHAR value to DATETIME and add -30 for subtraction. Also, In sql-server the format Fri, 14 Nov 2014 23:03:35 GMT was not converted to DATETIME. Try substring for it:

SELECT DATEADD(dd, -30, 
       CAST(SUBSTRING ('Fri, 14 Nov 2014 23:03:35 GMT', 6, 21) 
       AS DATETIME))

Properties file in python (similar to Java Properties)

import json
f=open('test.json')
x=json.load(f)
f.close()
print(x)

Contents of test.json: {"host": "127.0.0.1", "user": "jms"}

Display the binary representation of a number in C?

This code should handle your needs up to 64 bits.



char* pBinFill(long int x,char *so, char fillChar); // version with fill
char* pBin(long int x, char *so);                    // version without fill
#define width 64

char* pBin(long int x,char *so)
{
 char s[width+1];
 int    i=width;
 s[i--]=0x00;   // terminate string
 do
 { // fill in array from right to left
  s[i--]=(x & 1) ? '1':'0';  // determine bit
  x>>=1;  // shift right 1 bit
 } while( x > 0);
 i++;   // point to last valid character
 sprintf(so,"%s",s+i); // stick it in the temp string string
 return so;
}

char* pBinFill(long int x,char *so, char fillChar)
{ // fill in array from right to left
 char s[width+1];
 int    i=width;
 s[i--]=0x00;   // terminate string
 do
 {
  s[i--]=(x & 1) ? '1':'0';
  x>>=1;  // shift right 1 bit
 } while( x > 0);
 while(i>=0) s[i--]=fillChar;    // fill with fillChar 
 sprintf(so,"%s",s);
 return so;
}

void test()
{
 char so[width+1]; // working buffer for pBin
 long int   val=1;
 do
 {
   printf("%ld =\t\t%#lx =\t\t0b%s\n",val,val,pBinFill(val,so,0));
   val*=11; // generate test data
 } while (val < 100000000);
}

Output:
00000001 = 0x000001 =   0b00000000000000000000000000000001
00000011 = 0x00000b =   0b00000000000000000000000000001011
00000121 = 0x000079 =   0b00000000000000000000000001111001
00001331 = 0x000533 =   0b00000000000000000000010100110011
00014641 = 0x003931 =   0b00000000000000000011100100110001
00161051 = 0x02751b =   0b00000000000000100111010100011011
01771561 = 0x1b0829 =   0b00000000000110110000100000101001
19487171 = 0x12959c3 =  0b00000001001010010101100111000011

Hibernate: best practice to pull all lazy collections

There are some kind of misunderstanding about lazy collections in JPA-Hibernate. First of all let's clear that why trying to read a lazy collection throws exceptions and not just simply returns NULL for converting or further use cases?.

That's because Null fields in Databases especially in joined columns have meaning and not simply not-presented state, like programming languages. when you're trying to interpret a lazy collection to Null value it means (on Datastore-side) there is no relations between these entities and it's not true. so throwing exception is some kind of best-practice and you have to deal with that not the Hibernate.

So as mentioned above I recommend to :

  1. Detach the desired object before modifying it or using stateless session for querying
  2. Manipulate lazy fields to desired values (zero,null,etc.)

also as described in other answers there are plenty of approaches(eager fetch, joining etc.) or libraries and methods for doing that, but you have to setting up your view of what's happening before dealing with the problem and solving it.

Android device chooser - My device seems offline

Updated the Android SDK platform tools using SDK Manager (in Eclipse). Works for me.

difference between variables inside and outside of __init__()

Example code:

class inside:
    def __init__(self):
        self.l = []

    def insert(self, element):
        self.l.append(element)


class outside:
    l = []             # static variable - the same for all instances

    def insert(self, element):
        self.l.append(element)


def main():
    x = inside()
    x.insert(8)
    print(x.l)      # [8]
    y = inside()
    print(y.l)      # []
    # ----------------------------
    x = outside()
    x.insert(8)
    print(x.l)      # [8]
    y = outside()
    print(y.l)      # [8]           # here is the difference


if __name__ == '__main__':
    main()

Override browser form-filling and input highlighting with HTML/CSS

You can also change the name attribute of your form elements to be something generated so that the browser won't keep track of it. HOWEVER firefox 2.x+ and google chrome seems to not have much problems with that if the request url is identical. Try basically adding a salt request param and a salt field name for the sign-up form.

However I think autocomplete="off" is still top solution :)

mysql_config not found when installing mysqldb python interface

The MySQL-python package is using the mysql_config command to learn about the mysql configuration on your host. Your host does not have the mysql_config command.

The MySQL development libraries package (MySQL-devel-xxx) from dev.mysql.com provides this command and the libraries needed by the MySQL-python package. The MySQL-devel packages are found in the download - community server area. The MySQL development library package names start with MySQL-devel and vary based MySQL version and linux platform (e.g. MySQL-devel-5.5.24-1.linux2.6.x86_64.rpm.)

Note that you do not need to install mysql server.

How to replace (or strip) an extension from a filename in Python?

Expanding on AnaPana's answer, how to remove an extension using pathlib (Python >= 3.4):

>>> from pathlib import Path

>>> filename = Path('/some/path/somefile.txt')

>>> filename_wo_ext = filename.with_suffix('')

>>> filename_replace_ext = filename.with_suffix('.jpg')

>>> print(filename)
/some/path/somefile.ext    

>>> print(filename_wo_ext)
/some/path/somefile

>>> print(filename_replace_ext)
/some/path/somefile.jpg

FutureWarning: elementwise comparison failed; returning scalar, but in the future will perform elementwise comparison

In my case, the warning occurred because of just the regular type of boolean indexing -- because the series had only np.nan. Demonstration (pandas 1.0.3):

>>> import pandas as pd
>>> import numpy as np
>>> pd.Series([np.nan, 'Hi']) == 'Hi'
0    False
1     True
>>> pd.Series([np.nan, np.nan]) == 'Hi'
~/anaconda3/envs/ms3/lib/python3.7/site-packages/pandas/core/ops/array_ops.py:255: FutureWarning: elementwise comparison failed; returning scalar instead, but in the future will perform elementwise comparison
  res_values = method(rvalues)
0    False
1    False

I think with pandas 1.0 they really want you to use the new 'string' datatype which allows for pd.NA values:

>>> pd.Series([pd.NA, pd.NA]) == 'Hi'
0    False
1    False
>>> pd.Series([np.nan, np.nan], dtype='string') == 'Hi'
0    <NA>
1    <NA>
>>> (pd.Series([np.nan, np.nan], dtype='string') == 'Hi').fillna(False)
0    False
1    False

Don't love at which point they tinkered with every-day functionality such as boolean indexing.

Spark Dataframe distinguish columns with duplicated name

This is how we can join two Dataframes on same column names in PySpark.

df = df1.join(df2, ['col1','col2','col3'])

If you do printSchema() after this then you can see that duplicate columns have been removed.

How to get the list of files in a directory in a shell script?

The other answers on here are great and answer your question, but this is the top google result for "bash get list of files in directory", (which I was looking for to save a list of files) so I thought I would post an answer to that problem:

ls $search_path > filename.txt

If you want only a certain type (e.g. any .txt files):

ls $search_path | grep *.txt > filename.txt

Note that $search_path is optional; ls > filename.txt will do the current directory.

Reload the page after ajax success

You use the ajaxStop to execute code when the ajax are completed:

$(document).ajaxStop(function(){
  setTimeout("window.location = 'otherpage.html'",100);
});

Spring CORS No 'Access-Control-Allow-Origin' header is present

as @Geoffrey pointed out, with spring security, you need a different approach as described here: Spring Boot Security CORS

How to use wait and notify in Java without IllegalMonitorStateException?

You have properly guarded your code block when you call wait() method by using synchronized(this).

But you have not taken same precaution when you call notify() method without using guarded block : synchronized(this) or synchronized(someObject)

If you refer to oracle documentation page on Object class, which contains wait() ,notify(), notifyAll() methods, you can see below precaution in all these three methods

This method should only be called by a thread that is the owner of this object's monitor

Many things have been changed in last 7 years and let's have look into other alternatives to synchronized in below SE questions:

Why use a ReentrantLock if one can use synchronized(this)?

Synchronization vs Lock

Avoid synchronized(this) in Java?

How to debug "ImagePullBackOff"?

On GKE, if the pod is dead, it's best to check for the events. It will show in more detail what the error is about.

In my case, I had :

Failed to pull image "gcr.io/project/imagename@sha256:c8e91af54fc17faa1c49e2a05def5cbabf8f0a67fc558eb6cbca138061a8400a":
 rpc error: code = Unknown desc = error pulling image configuration: unknown blob

It turned out the image was damaged somehow. After repushing it and deploying with the new hash, it worked again.

AngularJS access parent scope from child controller

I believe I had a similar quandary recently

function parentCtrl() {
   var pc = this; // pc stands for parent control
   pc.foobar = 'SomeVal';
}

function childCtrl($scope) {

   // now how do I get the parent control 'foobar' variable?
   // I used $scope.$parent

   var parentFoobarVariableValue = $scope.$parent.pc.foobar;

   // that did it
}

My setup was a little different, but the same thing should probably still work

Change output format for MySQL command line results to CSV

If you are using mysql client you can set up the resultFormat per session e.g.

mysql -h localhost -u root --resutl-format=json

or

mysql -h localhost -u root --vertical

Check out the full list of arguments here.

Reading my own Jar's Manifest

I have this weird solution that runs war applications in a embedded Jetty server but these apps need also to run on standard Tomcat servers, and we have some special properties in the manfest.

The problem was that when in Tomcat, the manifest could be read, but when in jetty, a random manifest was picked up (which missed the special properties)

Based on Alex Konshin's answer, I came up with the following solution (the inputstream is then used in a Manifest class):

private static InputStream getWarManifestInputStreamFromClassJar(Class<?> cl ) {
    InputStream inputStream = null;
    try {
        URLClassLoader classLoader = (URLClassLoader)cl.getClassLoader();
        String classFilePath = cl.getName().replace('.','/')+".class";
        URL classUrl = classLoader.getResource(classFilePath);
        if ( classUrl==null ) return null;
        String classUri = classUrl.toString();
        if ( !classUri.startsWith("jar:") ) return null;
        int separatorIndex = classUri.lastIndexOf('!');
        if ( separatorIndex<=0 ) return null;
        String jarManifestUri = classUri.substring(0,separatorIndex+2);
        String containingWarManifestUri = jarManifestUri.substring(0,jarManifestUri.indexOf("WEB-INF")).replace("jar:file:/","file:///") + MANIFEST_FILE_PATH;
        URL url = new URL(containingWarManifestUri);
        inputStream = url.openStream();
        return inputStream;
    } catch ( Throwable e ) {
        // handle errors
        LOGGER.warn("No manifest file found in war file",e);
        return null;
    }
}

Import Error: No module named numpy

I also had this problem (Import Error: No module named numpy) but in my case it was a problem with my PATH variables in Mac OS X. I had made an earlier edit to my .bash_profile file that caused the paths for my Anaconda installation (and others) to not be added properly.

Just adding this comment to the list here in case other people like me come to this page with the same error message and have the same problem as I had.

import sun.misc.BASE64Encoder results in error compiled in Eclipse

Yup, and sun.misc.BASE64Decoder is way slower: 9x slower than java.xml.bind.DatatypeConverter.parseBase64Binary() and 4x slower than org.apache.commons.codec.binary.Base64.decodeBase64(), at least for a small string on Java 6 OSX.

Below is the test program I used. With Java 1.6.0_43 on OSX:

john:password = am9objpwYXNzd29yZA==
javax.xml took 373: john:password
apache took    612: john:password
sun took       2215: john:password

Btw that's with commons-codec 1.4. With 1.7 it seems to get slower:

javax.xml took 377: john:password
apache took    1681: john:password
sun took       2197: john:password

Didn't test Java 7 or other OS.

import javax.xml.bind.DatatypeConverter;
import org.apache.commons.codec.binary.Base64;
import java.io.IOException;

public class TestBase64 {
    private static volatile String save = null;
    public static void main(String argv[]) {
        String teststr = "john:password";
        String b64 = DatatypeConverter.printBase64Binary(teststr.getBytes());
        System.out.println(teststr + " = " + b64);
        try {
            final int COUNT = 1000000;
            long start;
            start = System.currentTimeMillis();
            for (int i=0; i<COUNT; ++i) {
                save = new String(DatatypeConverter.parseBase64Binary(b64));
            }
            System.out.println("javax.xml took "+(System.currentTimeMillis()-start)+": "+save);
            start = System.currentTimeMillis();
            for (int i=0; i<COUNT; ++i) {
                save = new String(Base64.decodeBase64(b64));
            }
            System.out.println("apache took    "+(System.currentTimeMillis()-start)+": "+save);
            sun.misc.BASE64Decoder dec = new sun.misc.BASE64Decoder();
            start = System.currentTimeMillis();
            for (int i=0; i<COUNT; ++i) {
                save = new String(dec.decodeBuffer(b64));
            }
            System.out.println("sun took       "+(System.currentTimeMillis()-start)+": "+save);
        } catch (Exception e) {
            System.out.println(e);
        }
    }
}

Git push failed, "Non-fast forward updates were rejected"

Pull changes first:

git pull origin branch_name

How can I change the font-size of a select option?

Tell the option element to be 13pt

select option{
    font-size: 13pt;
}

and then the first option element to be 7pt

select option:first-child {
    font-size: 7pt;
}

Running demo: http://jsfiddle.net/VggvD/1/

What is the most "pythonic" way to iterate over a list in chunks?

import itertools
def chunks(iterable,size):
    it = iter(iterable)
    chunk = tuple(itertools.islice(it,size))
    while chunk:
        yield chunk
        chunk = tuple(itertools.islice(it,size))

# though this will throw ValueError if the length of ints
# isn't a multiple of four:
for x1,x2,x3,x4 in chunks(ints,4):
    foo += x1 + x2 + x3 + x4

for chunk in chunks(ints,4):
    foo += sum(chunk)

Another way:

import itertools
def chunks2(iterable,size,filler=None):
    it = itertools.chain(iterable,itertools.repeat(filler,size-1))
    chunk = tuple(itertools.islice(it,size))
    while len(chunk) == size:
        yield chunk
        chunk = tuple(itertools.islice(it,size))

# x2, x3 and x4 could get the value 0 if the length is not
# a multiple of 4.
for x1,x2,x3,x4 in chunks2(ints,4,0):
    foo += x1 + x2 + x3 + x4

How to display Base64 images in HTML?

It is very simple.
As you say, it starts with data:image/jpeg;base64,. Below is an example taken from wikipedia, but it is only an example
I think that programing Base 64 encoded images is a little dificult, so there is an webapp to do that. Here is the link for the app: https://www.opinionatedgeek.com/codecs/base64decoder

_x000D_
_x000D_
<div>
  <img src="data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAAUA
    AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
        9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot" />
</div>
_x000D_
_x000D_
_x000D_ I know it just outputs an red dot, but it can be useful when you don't have space enough to put the images, something like that. But the problem is that this type of encoding is very long, so I don't know.

Converting Epoch time into the datetime

If you have epoch in milliseconds a possible solution is convert to seconds:

import time
time.ctime(milliseconds/1000)

For more time functions: https://docs.python.org/3/library/time.html#functions

How to initialize a vector of vectors on a struct?

Like this:

#include <vector>

// ...

std::vector<std::vector<int>> A(dimension, std::vector<int>(dimension));

(Pre-C++11 you need to leave whitespace between the angled brackets.)

Creating C formatted strings (not printing them)

Don't use sprintf.
It will overflow your String-Buffer and crash your Program.
Always use snprintf

What is DOM Event delegation?

The delegation concept

If there are many elements inside one parent, and you want to handle events on them of them - don’t bind handlers to each element. Instead, bind the single handler to their parent, and get the child from event.target. This site provides useful info about how to implement event delegation. http://javascript.info/tutorial/event-delegation

How do we count rows using older versions of Hibernate (~2009)?

It's very easy, just run the following JPQL query:

int count = (
(Number)
    entityManager
    .createQuery(
        "select count(b) " +
        "from Book b")
    .getSingleResult()
).intValue();

The reason we are casting to Number is that some databases will return Long while others will return BigInteger, so for portability sake you are better off casting to a Number and getting an int or a long, depending on how many rows you are expecting to be counted.

How to return a PNG image from Jersey REST service method to the browser

in regard of answer from @Perception, its true to be very memory-consuming when working with byte arrays, but you could also simply write back into the outputstream

@Path("/picture")
public class ProfilePicture {
  @GET
  @Path("/thumbnail")
  @Produces("image/png")
  public StreamingOutput getThumbNail() {
    return new StreamingOutput() {
      @Override
      public void write(OutputStream os) throws IOException, WebApplicationException {
        //... read your stream and write into os
      }
    };
  }
}

What's the best way of scraping data from a website?

You will definitely want to start with a good web scraping framework. Later on you may decide that they are too limiting and you can put together your own stack of libraries but without a lot of scraping experience your design will be much worse than pjscrape or scrapy.

Note: I use the terms crawling and scraping basically interchangeable here. This is a copy of my answer to your Quora question, it's pretty long.

Tools

Get very familiar with either Firebug or Chrome dev tools depending on your preferred browser. This will be absolutely necessary as you browse the site you are pulling data from and map out which urls contain the data you are looking for and what data formats make up the responses.

You will need a good working knowledge of HTTP as well as HTML and will probably want to find a decent piece of man in the middle proxy software. You will need to be able to inspect HTTP requests and responses and understand how the cookies and session information and query parameters are being passed around. Fiddler (http://www.telerik.com/fiddler) and Charles Proxy (http://www.charlesproxy.com/) are popular tools. I use mitmproxy (http://mitmproxy.org/) a lot as I'm more of a keyboard guy than a mouse guy.

Some kind of console/shell/REPL type environment where you can try out various pieces of code with instant feedback will be invaluable. Reverse engineering tasks like this are a lot of trial and error so you will want a workflow that makes this easy.

Language

PHP is basically out, it's not well suited for this task and the library/framework support is poor in this area. Python (Scrapy is a great starting point) and Clojure/Clojurescript (incredibly powerful and productive but a big learning curve) are great languages for this problem. Since you would rather not learn a new language and you already know Javascript I would definitely suggest sticking with JS. I have not used pjscrape but it looks quite good from a quick read of their docs. It's well suited and implements an excellent solution to the problem I describe below.

A note on Regular expressions: DO NOT USE REGULAR EXPRESSIONS TO PARSE HTML. A lot of beginners do this because they are already familiar with regexes. It's a huge mistake, use xpath or css selectors to navigate html and only use regular expressions to extract data from actual text inside an html node. This might already be obvious to you, it becomes obvious quickly if you try it but a lot of people waste a lot of time going down this road for some reason. Don't be scared of xpath or css selectors, they are WAY easier to learn than regexes and they were designed to solve this exact problem.

Javascript-heavy sites

In the old days you just had to make an http request and parse the HTML reponse. Now you will almost certainly have to deal with sites that are a mix of standard HTML HTTP request/responses and asynchronous HTTP calls made by the javascript portion of the target site. This is where your proxy software and the network tab of firebug/devtools comes in very handy. The responses to these might be html or they might be json, in rare cases they will be xml or something else.

There are two approaches to this problem:

The low level approach:

You can figure out what ajax urls the site javascript is calling and what those responses look like and make those same requests yourself. So you might pull the html from http://example.com/foobar and extract one piece of data and then have to pull the json response from http://example.com/api/baz?foo=b... to get the other piece of data. You'll need to be aware of passing the correct cookies or session parameters. It's very rare, but occasionally some required parameters for an ajax call will be the result of some crazy calculation done in the site's javascript, reverse engineering this can be annoying.

The embedded browser approach:

Why do you need to work out what data is in html and what data comes in from an ajax call? Managing all that session and cookie data? You don't have to when you browse a site, the browser and the site javascript do that. That's the whole point.

If you just load the page into a headless browser engine like phantomjs it will load the page, run the javascript and tell you when all the ajax calls have completed. You can inject your own javascript if necessary to trigger the appropriate clicks or whatever is necessary to trigger the site javascript to load the appropriate data.

You now have two options, get it to spit out the finished html and parse it or inject some javascript into the page that does your parsing and data formatting and spits the data out (probably in json format). You can freely mix these two options as well.

Which approach is best?

That depends, you will need to be familiar and comfortable with the low level approach for sure. The embedded browser approach works for anything, it will be much easier to implement and will make some of the trickiest problems in scraping disappear. It's also quite a complex piece of machinery that you will need to understand. It's not just HTTP requests and responses, it's requests, embedded browser rendering, site javascript, injected javascript, your own code and 2-way interaction with the embedded browser process.

The embedded browser is also much slower at scale because of the rendering overhead but that will almost certainly not matter unless you are scraping a lot of different domains. Your need to rate limit your requests will make the rendering time completely negligible in the case of a single domain.

Rate Limiting/Bot behaviour

You need to be very aware of this. You need to make requests to your target domains at a reasonable rate. You need to write a well behaved bot when crawling websites, and that means respecting robots.txt and not hammering the server with requests. Mistakes or negligence here is very unethical since this can be considered a denial of service attack. The acceptable rate varies depending on who you ask, 1req/s is the max that the Google crawler runs at but you are not Google and you probably aren't as welcome as Google. Keep it as slow as reasonable. I would suggest 2-5 seconds between each page request.

Identify your requests with a user agent string that identifies your bot and have a webpage for your bot explaining it's purpose. This url goes in the agent string.

You will be easy to block if the site wants to block you. A smart engineer on their end can easily identify bots and a few minutes of work on their end can cause weeks of work changing your scraping code on your end or just make it impossible. If the relationship is antagonistic then a smart engineer at the target site can completely stymie a genius engineer writing a crawler. Scraping code is inherently fragile and this is easily exploited. Something that would provoke this response is almost certainly unethical anyway, so write a well behaved bot and don't worry about this.

Testing

Not a unit/integration test person? Too bad. You will now have to become one. Sites change frequently and you will be changing your code frequently. This is a large part of the challenge.

There are a lot of moving parts involved in scraping a modern website, good test practices will help a lot. Many of the bugs you will encounter while writing this type of code will be the type that just return corrupted data silently. Without good tests to check for regressions you will find out that you've been saving useless corrupted data to your database for a while without noticing. This project will make you very familiar with data validation (find some good libraries to use) and testing. There are not many other problems that combine requiring comprehensive tests and being very difficult to test.

The second part of your tests involve caching and change detection. While writing your code you don't want to be hammering the server for the same page over and over again for no reason. While running your unit tests you want to know if your tests are failing because you broke your code or because the website has been redesigned. Run your unit tests against a cached copy of the urls involved. A caching proxy is very useful here but tricky to configure and use properly.

You also do want to know if the site has changed. If they redesigned the site and your crawler is broken your unit tests will still pass because they are running against a cached copy! You will need either another, smaller set of integration tests that are run infrequently against the live site or good logging and error detection in your crawling code that logs the exact issues, alerts you to the problem and stops crawling. Now you can update your cache, run your unit tests and see what you need to change.

Legal Issues

The law here can be slightly dangerous if you do stupid things. If the law gets involved you are dealing with people who regularly refer to wget and curl as "hacking tools". You don't want this.

The ethical reality of the situation is that there is no difference between using browser software to request a url and look at some data and using your own software to request a url and look at some data. Google is the largest scraping company in the world and they are loved for it. Identifying your bots name in the user agent and being open about the goals and intentions of your web crawler will help here as the law understands what Google is. If you are doing anything shady, like creating fake user accounts or accessing areas of the site that you shouldn't (either "blocked" by robots.txt or because of some kind of authorization exploit) then be aware that you are doing something unethical and the law's ignorance of technology will be extraordinarily dangerous here. It's a ridiculous situation but it's a real one.

It's literally possible to try and build a new search engine on the up and up as an upstanding citizen, make a mistake or have a bug in your software and be seen as a hacker. Not something you want considering the current political reality.

Who am I to write this giant wall of text anyway?

I've written a lot of web crawling related code in my life. I've been doing web related software development for more than a decade as a consultant, employee and startup founder. The early days were writing perl crawlers/scrapers and php websites. When we were embedding hidden iframes loading csv data into webpages to do ajax before Jesse James Garrett named it ajax, before XMLHTTPRequest was an idea. Before jQuery, before json. I'm in my mid-30's, that's apparently considered ancient for this business.

I've written large scale crawling/scraping systems twice, once for a large team at a media company (in Perl) and recently for a small team as the CTO of a search engine startup (in Python/Javascript). I currently work as a consultant, mostly coding in Clojure/Clojurescript (a wonderful expert language in general and has libraries that make crawler/scraper problems a delight)

I've written successful anti-crawling software systems as well. It's remarkably easy to write nigh-unscrapable sites if you want to or to identify and sabotage bots you don't like.

I like writing crawlers, scrapers and parsers more than any other type of software. It's challenging, fun and can be used to create amazing things.

How do you perform a left outer join using linq extension methods

Group Join method is unnecessary to achieve joining of two data sets.

Inner Join:

var qry = Foos.SelectMany
            (
                foo => Bars.Where (bar => foo.Foo_id == bar.Foo_id),
                (foo, bar) => new
                    {
                    Foo = foo,
                    Bar = bar
                    }
            );

For Left Join just add DefaultIfEmpty()

var qry = Foos.SelectMany
            (
                foo => Bars.Where (bar => foo.Foo_id == bar.Foo_id).DefaultIfEmpty(),
                (foo, bar) => new
                    {
                    Foo = foo,
                    Bar = bar
                    }
            );

EF and LINQ to SQL correctly transform to SQL. For LINQ to Objects it is beter to join using GroupJoin as it internally uses Lookup. But if you are querying DB then skipping of GroupJoin is AFAIK as performant.

Personlay for me this way is more readable compared to GroupJoin().SelectMany()

connect local repo with remote repo

I know it has been quite sometime that you asked this but, if someone else needs, I did what was saying here " How to upload a project to Github " and after the top answer of this question right here. And after was the top answer was saying here "git error: failed to push some refs to" I don't know what exactly made everything work. But now is working.

How can I quickly delete a line in VIM starting at the cursor position?

This is a very old question, but as VIM is still relevant something should be clarified.

Every answer and comment here as of October 2018 has referred to what would commonly be known as a "cut" action, thus using any of them will replace whatever is currently in VIM's unnamed register. This register tends to be treated like a default copy/paste clipboard, so none of these answers will work as desired if you are deleting the rest of a line to paste something in the same place afterward, as whatever was just deleted will be subsequently pasted in place of whatever was yanked before.

The true delete command in the OP's context is "_D (or "_C if insert mode is desired) This sends the deleted content into the black hole register, designated by "_, where it will bother no one ever again (although you can still undo this action using u).

That being said, whatever was last yanked is stored in the 0 register, and even if it gets replaced in the unnamed register, it can still be pasted using "0p.

Learn more about the black hole register and registers in general for extra VIM fun!

CSS transition shorthand with multiple properties?

I think that this should work:

.element {
   -webkit-transition: all .3s;
   -moz-transition: all .3s;
   -o-transition: all .3s;
   transition: all .3s;
}

How do we control web page caching, across all browsers?

I had no luck with <head><meta> elements. Adding HTTP cache related parameters directly (outside of the HTML doc) does indeed work for me.

Sample code in Python using web.py web.header calls follows. I purposefully redacted my personal irrelevant utility code.


    import web
    import sys
    import PERSONAL-UTILITIES

    myname = "main.py"

    urls = (
        '/', 'main_class'
    )

    main = web.application(urls, globals())

    render = web.template.render("templates/", base="layout", cache=False)

    class main_class(object):
        def GET(self):
            web.header("Cache-control","no-cache, no-store, must-revalidate")
            web.header("Pragma", "no-cache")
            web.header("Expires", "0")
            return render.main_form()

        def POST(self):
            msg = "POSTed:"
            form = web.input(function = None)
            web.header("Cache-control","no-cache, no-store, must-revalidate")
            web.header("Pragma", "no-cache")
            web.header("Expires", "0")
            return render.index_laid_out(greeting = msg + form.function)

    if __name__ == "__main__":
        nargs = len(sys.argv)
        # Ensure that there are enough arguments after python program name
        if nargs != 2:
            LOG-AND-DIE("%s: Command line error, nargs=%s, should be 2", myname, nargs)
        # Make sure that the TCP port number is numeric
        try:
            tcp_port = int(sys.argv[1])
        except Exception as e:
            LOG-AND-DIE ("%s: tcp_port = int(%s) failed (not an integer)", myname, sys.argv[1])
        # All is well!
        JUST-LOG("%s: Running on port %d", myname, tcp_port)
        web.httpserver.runsimple(main.wsgifunc(), ("localhost", tcp_port))
        main.run()

Oracle SQL convert date format from DD-Mon-YY to YYYYMM

As offer_date is an number, and is of lower accuracy than your real dates, this may work...
- Convert your real date to a string of format YYYYMM
- Conver that value to an INT
- Compare the result you your offer_date

SELECT
  *
FROM
  offers
WHERE
    offer_date = (SELECT CAST(to_char(create_date, 'YYYYMM') AS INT) FROM customers where id = '12345678')
AND offer_rate > 0 

Also, by doing all the manipulation on the create_date you only do the processing on one value.

Additionally, had you manipulated the offer_date you would not be able to utilise any index on that field, and so force SCANs instead of SEEKs.

Check if string ends with one of the strings from a list

Take an extension from the file and see if it is in the set of extensions:

>>> import os
>>> extensions = set(['.mp3','.avi'])
>>> file_name = 'test.mp3'
>>> extension = os.path.splitext(file_name)[1]
>>> extension in extensions
True

Using a set because time complexity for lookups in sets is O(1) (docs).

(HTML) Download a PDF file instead of opening them in browser when clicked

I needed to do this for files created with dynamic names in a particular folder and served by IIS.

This worked for me:

  • In IIS, go that folder and double click HTTP Response Headers.
  • Add a new header with the following info:

    Name: content-disposition Value: attachment

(from: http://forums.iis.net/t/1175103.aspx?add+CustomHeaders+only+for+certain+file+types+)

Google Maps JavaScript API RefererNotAllowedMapError

This worked for me. There are 2 major categories of restrictions under api key settings:

  • Application restrictions
  • API restrictions

Application restrictions:

At the bottom in the Referrer section add your website url " http://www.grupocamaleon.com/boceto/aerial-simple.html " .There are example rules on the right hand side of the section based on various requirements.

Application restrictions

API restrictions:

Under API restrictions you have to explicitly select 'Maps Javascript API' from the dropdown list since our unique key will only be used for calling the Google maps API(probably) and save it as you can see in the below snap. I hope this works for you.....worked for me

enter image description here

Check your Script:

Also the issue may arise due to improper key feeding inside the script tag. It should be something like:

  <script async defer src="https://maps.googleapis.com/maps/api/jskey=YOUR_API_KEY&callback=initMap"
  type="text/javascript"></script>

How can I retrieve the remote git address of a repo?

The long boring solution, which is not involved with CLI, you can manually navigate to:

your local repo folder ? .git folder (hidden) ? config file

then choose your text editor to open it and look for url located under the [remote "origin"] section.

How to install Visual C++ Build tools?

The current version (2019/03/07) is Build Tools for Visual Studio 2017. It's an online installer, you need to include at least the individual components:

  • VC++ 2017 version xx.x tools
  • Windows SDK to use standard libraries.

How do I get a python program to do nothing?

you can use pass inside if statement.

Bootstrap 4 File Input

You can try below given snippet to display the selected file name from the file input type.

document.querySelectorAll('input[type=file]').forEach( input => {
    input.addEventListener('change', e => {
        e.target.nextElementSibling.innerText = input.files[0].name;
    });
});

How to connect to a remote Windows machine to execute commands using python?

Maybe you can use SSH to connect to a remote server.

Install freeSSHd on your windows server.

SSH Client connection Code:

import paramiko

hostname = "your-hostname"
username = "your-username"
password = "your-password"
cmd = 'your-command'

try:
    ssh = paramiko.SSHClient()
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    ssh.connect(hostname,username=username,password=password)
    print("Connected to %s" % hostname)
except paramiko.AuthenticationException:
    print("Failed to connect to %s due to wrong username/password" %hostname)
    exit(1)
except Exception as e:
    print(e.message)    
    exit(2)

Execution Command and get feedback:

try:
    stdin, stdout, stderr = ssh.exec_command(cmd)
except Exception as e:
    print(e.message)

err = ''.join(stderr.readlines())
out = ''.join(stdout.readlines())
final_output = str(out)+str(err)
print(final_output)

dpi value of default "large", "medium" and "small" text views android

Programmatically, you could use:

textView.setTextAppearance(android.R.style.TextAppearance_Large);

How to convert int to string on Arduino?

This simply work for me:

int bpm = 60;
char text[256];
sprintf(text, "Pulso: %d     ", bpm);
//now use text as string

How do you delete all text above a certain line

d1G = delete to top including current line (vi)

Difference between [routerLink] and routerLink

Assume that you have

const appRoutes: Routes = [
  {path: 'recipes', component: RecipesComponent }
];

<a routerLink ="recipes">Recipes</a>

It means that clicking Recipes hyperlink will jump to http://localhost:4200/recipes

Assume that the parameter is 1

<a [routerLink] = "['/recipes', parameter]"></a>

It means that passing dynamic parameter, 1 to the link, then you navigate to http://localhost:4200/recipes/1

Running Python on Windows for Node.js dependencies

I met the same challenge while trying to install [email protected].

And after looking at the current official documentation, and having read the answers above, i noticed that you might not necessarily have to install node-gyp nor install windows-build tools. This is what it says, here about installing node-gyp on windows. Remember node-gyp is involved in the installation process of node-sass. And you don't really have to re-install another python version.

This is the savior, configure the python path that "npm" should look for while installing any packages that require build-tools.

C:\> npm config set python /Python36/python

I had installed python3.6.3, on windows-7, there.

Trying to start a service on boot on Android

How to start service on device boot(autorun app, etc.)

For first: since version Android 3.1+ you don't receive BOOT_COMPLETE if user never started your app at least once or user "force closed" application. This was done to prevent malware automatically register service. This security hole was closed in newer versions of Android.

Solution:

Create app with activity. When user run it once app can receive BOOT_COMPLETE broadcast message.

For second: BOOT_COMPLETE is sent before external storage is mounted. If app is installed to external storage it won't receive BOOT_COMPLETE broadcast message.

In this case there is two solution:

  1. Install your app to internal storage
  2. Install another small app in internal storage. This app receives BOOT_COMPLETE and run second app on external storage.

If your app already installed in internal storage then code below can help you understand how to start service on device boot.


In Manifest.xml

Permission:

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

Register your BOOT_COMPLETED receiver:

<receiver android:name="org.yourapp.OnBoot">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"/>
    </intent-filter>
</receiver>

Register your service:

<service android:name="org.yourapp.YourCoolService" />

In receiver OnBoot.java:

public class OnBoot extends BroadcastReceiver
{

    @Override
    public void onReceive(Context context, Intent intent) 
    {
        // Create Intent
        Intent serviceIntent = new Intent(context, YourCoolService.class);
        // Start service
        context.startService(serviceIntent);

    }

 }

For HTC you maybe need also add in Manifest this code if device don't catch RECEIVE_BOOT_COMPLETED:

<action android:name="android.intent.action.QUICKBOOT_POWERON" />

Receiver now look like this:

<receiver android:name="org.yourapp.OnBoot">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"/>
        <action android:name="android.intent.action.QUICKBOOT_POWERON" />
    </intent-filter>
</receiver>

How to test BOOT_COMPLETED without restart emulator or real device? It's easy. Try this:

adb -s device-or-emulator-id shell am broadcast -a android.intent.action.BOOT_COMPLETED

How to get device id? Get list of connected devices with id's:

adb devices

adb in ADT by default you can find in:

adt-installation-dir/sdk/platform-tools

Enjoy! )

Download file of any type in Asp.Net MVC using FileResult?

You can just specify the generic octet-stream MIME type:

public FileResult Download()
{
    byte[] fileBytes = System.IO.File.ReadAllBytes(@"c:\folder\myfile.ext");
    string fileName = "myfile.ext";
    return File(fileBytes, System.Net.Mime.MediaTypeNames.Application.Octet, fileName);
}

How to delete an instantiated object Python?

What do you mean by delete? In Python, removing a reference (or a name) can be done with the del keyword, but if there are other names to the same object that object will not be deleted.

--> test = 3
--> print(test)
3
--> del test
--> print(test)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'test' is not defined

compared to:

--> test = 5
--> other is test  # check that both name refer to the exact same object
True
--> del test       # gets rid of test, but the object is still referenced by other
--> print(other)
5

How can I enable the Windows Server Task Scheduler History recording?

I think the confusion is that on my server I had to right click the Task Scheduler Library on left hand side and right click to get the option to enable or disable all tasks history.

Hope this helps

Can anyone explain python's relative imports?

Checking it out in python3:

python -V
Python 3.6.5

Example1:

.
+-- parent.py
+-- start.py
+-- sub
    +-- relative.py

- start.py
import sub.relative

- parent.py
print('Hello from parent.py')

- sub/relative.py
from .. import parent

If we run it like this(just to make sure PYTHONPATH is empty):

PYTHONPATH='' python3 start.py

Output:

Traceback (most recent call last):
  File "start.py", line 1, in <module>
    import sub.relative
  File "/python-import-examples/so-example-v1/sub/relative.py", line 1, in <module>
    from .. import parent
ValueError: attempted relative import beyond top-level package

If we change import in sub/relative.py

- sub/relative.py
import parent

If we run it like this:

PYTHONPATH='' python3 start.py

Output:

Hello from parent.py

Example2:

.
+-- parent.py
+-- sub
    +-- relative.py
    +-- start.py

- parent.py
print('Hello from parent.py')

- sub/relative.py
print('Hello from relative.py')

- sub/start.py
import relative
from .. import parent

Run it like:

PYTHONPATH='' python3 sub/start.py

Output:

Hello from relative.py
Traceback (most recent call last):
  File "sub/start.py", line 2, in <module>
    from .. import parent
ValueError: attempted relative import beyond top-level package

If we change import in sub/start.py:

- sub/start.py
import relative
import parent

Run it like:

PYTHONPATH='' python3 sub/start.py

Output:

Hello from relative.py
Traceback (most recent call last):
  File "sub/start.py", line 3, in <module>
    import parent
ModuleNotFoundError: No module named 'parent'

Run it like:

PYTHONPATH='.' python3 sub/start.py

Output:

Hello from relative.py
Hello from parent.py

Also it's better to use import from root folder, i.e.:

- sub/start.py
import sub.relative
import parent

Run it like:

PYTHONPATH='.' python3 sub/start.py

Output:

Hello from relative.py
Hello from parent.py

How to create a <style> tag with Javascript?

If the problem you're facing is injecting a string of CSS into a page it is easier to do this with the <link> element than the <style> element.

The following adds p { color: green; } rule to the page.

<link rel="stylesheet" type="text/css" href="data:text/css;charset=UTF-8,p%20%7B%20color%3A%20green%3B%20%7D" />

You can create this in JavaScript simply by URL encoding your string of CSS and adding it the HREF attribute. Much simpler than all the quirks of <style> elements or directly accessing stylesheets.

let linkElement: HTMLLinkElement = this.document.createElement('link');
linkElement.setAttribute('rel', 'stylesheet');
linkElement.setAttribute('type', 'text/css');
linkElement.setAttribute('href', 'data:text/css;charset=UTF-8,' + encodeURIComponent(myStringOfstyles));

This will work in IE 5.5 upwards

Save and retrieve image (binary) from SQL Server using Entity Framework 6

Convert the image to a byte[] and store that in the database.


Add this column to your model:

public byte[] Content { get; set; }

Then convert your image to a byte array and store that like you would any other data:

public byte[] ImageToByteArray(System.Drawing.Image imageIn)
{
    using(var ms = new MemoryStream())
    {
        imageIn.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);

        return ms.ToArray();
    }
}

public Image ByteArrayToImage(byte[] byteArrayIn)
{
     using(var ms = new MemoryStream(byteArrayIn))
     {
         var returnImage = Image.FromStream(ms);

         return returnImage;
     }
}

Source: Fastest way to convert Image to Byte array

var image = new ImageEntity()
{
   Content = ImageToByteArray(image)
};

_context.Images.Add(image);
_context.SaveChanges();

When you want to get the image back, get the byte array from the database and use the ByteArrayToImage and do what you wish with the Image

This stops working when the byte[] gets to big. It will work for files under 100Mb

UIDevice uniqueIdentifier deprecated - What to do now?

This is code I'm using to get ID for both iOS 5 and iOS 6, 7:

- (NSString *) advertisingIdentifier
{
    if (!NSClassFromString(@"ASIdentifierManager")) {
        SEL selector = NSSelectorFromString(@"uniqueIdentifier");
        if ([[UIDevice currentDevice] respondsToSelector:selector]) {
            return [[UIDevice currentDevice] performSelector:selector];
        }
    }
    return [[[ASIdentifierManager sharedManager] advertisingIdentifier] UUIDString];
}

How do I disable right click on my web page?

You can do that with JavaScript by adding an event listener for the "contextmenu" event and calling the preventDefault() method:

document.addEventListener('contextmenu', event => event.preventDefault());

That being said: DON'T DO IT.

Why? Because it achieves nothing other than annoying users. Also many browsers have a security option to disallow disabling of the right click (context) menu anyway.

Not sure why you'd want to. If it's out of some misplaced belief that you can protect your source code or images that way, think again: you can't.

Bootstrap Element 100% Width

This is how you can achieve your desired setup with Bootstrap 3:

<div class="container-fluid">
    <div class="row"> <!-- Give this div your desired background color -->
        <div class="container">
            <div class="row">
                <div class="col-md-12">
                    ... your content here ...
                </div>
            </div>
        </div>
    </div>
</div>

The container-fluid part makes sure that you can change the background over the full width. The container part makes sure that your content is still wrapped in a fixed width.

This approach works, but personally I don't like all the nesting. However, I haven't found a better solution so far.

Simulating Slow Internet Connection

Updating this (9 years after it was asked) as the answer I was looking for wasn't mentioned:

Firefox also has presets for throttling connection speeds. Find them in the Network Monitor tab of the developer tools. Default is 'No throttling'.

Slowest is GPRS (Download speed: 50 Kbps, Upload speed: 20 Kbps, Minimum latency (ms): 500), ranging through 'good' and 'regular' 2G, 3G and 4G to DSL and WiFi (Download speed: 30Mbps, Upload speed: 15Mbps, Minimum latency (ms): 2).

More in the Dev Tools docs.

Is there an auto increment in sqlite?

Have you read this? How do I create an AUTOINCREMENT field.

INSERT INTO people
VALUES (NULL, "John", "Smith");

Change border-bottom color using jquery?

If you have this in your CSS file:

.myApp
{
    border-bottom-color:#FF0000;
}

and a div for instance of:

<div id="myDiv">test text</div>

you can use:

$("#myDiv").addClass('myApp');// to add the style

$("#myDiv").removeClass('myApp');// to remove the style

or you can just use

$("#myDiv").css( 'border-bottom-color','#FF0000');

I prefer the first example, keeping all the CSS related items in the CSS files.

Getting all types in a namespace via reflection

using System.Reflection;
using System.Collections.Generic;
//...

static List<string> GetClasses(string nameSpace)
{
    Assembly asm = Assembly.GetExecutingAssembly();

    List<string> namespacelist = new List<string>();
    List<string> classlist = new List<string>();

    foreach (Type type in asm.GetTypes())
    {
        if (type.Namespace == nameSpace)
            namespacelist.Add(type.Name);
    }

    foreach (string classname in namespacelist)
        classlist.Add(classname);

    return classlist;
}

NB: The above code illustrates what's going on. Were you to implement it, a simplified version can be used:

using System.Linq;
using System.Reflection;
using System.Collections.Generic;
//...

static IEnumerable<string> GetClasses(string nameSpace)
{
    Assembly asm = Assembly.GetExecutingAssembly();
    return asm.GetTypes()
        .Where(type => type.Namespace == nameSpace)
        .Select(type => type.Name);
}

Checking if a folder exists (and creating folders) in Qt, C++

If you need an empty folder you can loop until you get an empty folder

    QString folder= QString ("%1").arg(QDateTime::currentMSecsSinceEpoch());
    while(QDir(folder).exists())
    {
         folder= QString ("%1").arg(QDateTime::currentMSecsSinceEpoch());
    }
    QDir().mkdir(folder);

This case you will get a folder name with a number .

How to pass an array to a function in VBA?

Your function worked for me after changing its declaration to this ...

Function processArr(Arr As Variant) As String

You could also consider a ParamArray like this ...

Function processArr(ParamArray Arr() As Variant) As String
    'Dim N As Variant
    Dim N As Long
    Dim finalStr As String
    For N = LBound(Arr) To UBound(Arr)
        finalStr = finalStr & Arr(N)
    Next N
    processArr = finalStr
End Function

And then call the function like this ...

processArr("foo", "bar")

JQuery - Storing ajax response into global variable

IMO you can store this data in global variable. But it will be better to use some more unique name or use namespace:

MyCompany = {};

...
MyCompany.cachedData = data;

And also it's better to use json for these purposes, data in json format is usually much smaller than the same data in xml format.

add to array if it isn't there already

If you don't care about the ordering of the keys, you could do the following:

$array = YOUR_ARRAY
$unique = array();
foreach ($array as $a) {
    $unique[$a] = $a;
}

How to disable keypad popup when on edittext?

private InputMethodManager imm;

...


editText.setOnTouchListener(new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        v.onTouchEvent(event);
        hideDefaultKeyboard(v);
        return true;
    }
});

private void hideDefaultKeyboard(View et) {
  getMethodManager().hideSoftInputFromWindow(et.getWindowToken(), 0);
}

private InputMethodManager getMethodManager() {
        if (this.imm == null) {
            this.imm = (InputMethodManager)  getContext().getSystemService(android.content.Context.INPUT_METHOD_SERVICE);
        }
  return this.imm;
}

How do I test which class an object is in Objective-C?

if you want to get the name of the class simply call:-

id yourObject= [AnotherClass returningObject];

NSString *className=[yourObject className];

NSLog(@"Class name is : %@",className);

How to remove entity with ManyToMany relationship in JPA (and corresponding join table rows)?

As an alternative to JPA/Hibernate solutions : you could use a CASCADE DELETE clause in the database definition of your foregin key on your join table, such as (Oracle syntax) :

CONSTRAINT fk_to_group
     FOREIGN KEY (group_id)
     REFERENCES group (id)
     ON DELETE CASCADE

That way the DBMS itself automatically deletes the row that points to the group when you delete the group. And it works whether the delete is made from Hibernate/JPA, JDBC, manually in the DB or any other way.

the cascade delete feature is supported by all major DBMS (Oracle, MySQL, SQL Server, PostgreSQL).

React Modifying Textarea Values

I think you want something along the line of:

Parent:

<Editor name={this.state.fileData} />

Editor:

var Editor = React.createClass({
  displayName: 'Editor',
  propTypes: {
    name: React.PropTypes.string.isRequired
  },
  getInitialState: function() { 
    return {
      value: this.props.name
    };
  },
  handleChange: function(event) {
    this.setState({value: event.target.value});
  },
  render: function() {
    return (
      <form id="noter-save-form" method="POST">
        <textarea id="noter-text-area" name="textarea" value={this.state.value} onChange={this.handleChange} />
        <input type="submit" value="Save" />
      </form>
    );
  }
});

This is basically a direct copy of the example provided on https://facebook.github.io/react/docs/forms.html

Update for React 16.8:

import React, { useState } from 'react';

const Editor = (props) => {
    const [value, setValue] = useState(props.name);

    const handleChange = (event) => {
        setValue(event.target.value);
    };

    return (
        <form id="noter-save-form" method="POST">
            <textarea id="noter-text-area" name="textarea" value={value} onChange={handleChange} />
            <input type="submit" value="Save" />
        </form>
    );
}

Editor.propTypes = {
    name: PropTypes.string.isRequired
};

Open source PDF library for C/C++ application?

Try wkhtmltopdf

Software features

Cross platform. Open source. Convert any web pages into PDF documents using webkit. You can add headers and footers. TOC generation. Batch mode conversions. Can run on Linux server with an XServer (the X11 client libs must be installed). Can be directly used by PHP or Python via bindings to libwkhtmltox.

How can you tell if a value is not numeric in Oracle?

The best answer I found on internet:

SELECT case when trim(TRANSLATE(col1, '0123456789-,.', ' ')) is null
            then 'numeric'
            else 'alpha'
       end
FROM tab1;

How to match, but not capture, part of a regex?

Try this:

/\d{3}-(?:(apple|banana)-)?\d{3}/

phpmyadmin "Not Found" after install on Apache, Ubuntu

It seems like sometime during the second half of 2018 many php packages such as php-mysql and phpmyadmin were removed or changed. I faced that same problem too. So you'll have to download it from another source or find out the new packages

Representing null in JSON

null is not zero. It is not a value, per se: it is a value outside the domain of the variable indicating missing or unknown data.

There is only one way to represent null in JSON. Per the specs (RFC 4627 and json.org):

2.1.  Values

A JSON value MUST be an object, array, number, or string, or one of
the following three literal names:

  false null true

enter image description here

What is INSTALL_PARSE_FAILED_NO_CERTIFICATES error?

Make sure the build variant is set to debug (and not release) in Android Studio (check the build variants panel).

Disable beep of Linux Bash on Windows 10

You need add following lines to bash and vim config,

1) Turn off bell for bash

vi ~/.inputrc
set bell-style none

2) Turn off bell for vi

vi ~/.vimrc
set visualbell
set t_vb=

Setting the visual bell turns off the audio bell and clearing the visual bell length deactivates flashing.

using favicon with css

If (1) you need a favicon that is different for some parts of the domain, or (2) you want this to work with IE 8 or older (haven't tested any newer version), then you have to edit the html to specify the favicon

What does $1 [QSA,L] mean in my .htaccess file?

If the following conditions are true, then rewrite the URL:
If the requested filename is not a directory,

RewriteCond %{REQUEST_FILENAME} !-d

and if the requested filename is not a regular file that exists,

RewriteCond %{REQUEST_FILENAME} !-f

and if the requested filename is not a symbolic link,

RewriteCond %{REQUEST_FILENAME} !-l

then rewrite the URL in the following way:
Take the whole request filename and provide it as the value of a "url" query parameter to index.php. Append any query string from the original URL as further query parameters (QSA), and stop processing this .htaccess file (L).

RewriteRule ^(.+)$ index.php?url=$1 [QSA,L]

Apache docs #flag_qsa

Another Example:

RewriteRule "/pages/(.+)" "/page.php?page=$1" [QSA]

With the [QSA] flag, a request for

/pages/123?one=two

will be mapped to

/page.php?page=123&one=two

How do I force Kubernetes to re-pull an image?

There is a comand to directly do that:

Create a new kubectl rollout restart command that does a rolling restart of a deployment.

The pull request got merged. It is part of the version 1.15 (changelog) or higher.

Popup window in PHP?

You'll have to use JS to open the popup, though you can put it on the page conditionally with PHP, you're right that you'll have to use a JavaScript function.

How can I call a shell command in my Perl script?

How to run a shell script from a Perl program

1. Using system system($command, @arguments);

For example:

system("sh", "script.sh", "--help" );

system("sh script.sh --help");

System will execute the $command with @arguments and return to your script when finished. You may check $! for certain errors passed to the OS by the external application. Read the documentation for system for the nuances of how various invocations are slightly different.

2. Using exec

This is very similar to the use of system, but it will terminate your script upon execution. Again, read the documentation for exec for more.

3. Using backticks or qx//

my $output = `script.sh --option`;

my $output = qx/script.sh --option/;

The backtick operator and it's equivalent qx//, excute the command and options inside the operator and return that commands output to STDOUT when it finishes.

There are also ways to run external applications through creative use of open, but this is advanced use; read the documentation for more.

How to set OnClickListener on a RadioButton in Android?

Since this question isn't specific to Java, I would like to add how you can do it in Kotlin:

radio_group_id.setOnCheckedChangeListener({ radioGroup, optionId -> {
        when (optionId) {
            R.id.radio_button_1 -> {
                // do something when radio button 1 is selected
            }
            // add more cases here to handle other buttons in the RadioGroup
        }
    }
})

Here radio_group_id is the assigned android:id of the concerned RadioGroup. To use it this way you would need to import kotlinx.android.synthetic.main.your_layout_name.* in your activity's Kotlin file. Also note that in case the radioGroup lambda parameter is unused, it can be replaced with _ (an underscore) since Kotlin 1.1.

How to use SearchView in Toolbar Android

If you would like to setup the search facility inside your Fragment, just add these few lines:

Step 1 - Add the search field to you toolbar:

<item
    android:id="@+id/action_search"
    android:icon="@android:drawable/ic_menu_search"
    app:showAsAction="always|collapseActionView"
    app:actionViewClass="android.support.v7.widget.SearchView"
    android:title="Search"/>

Step 2 - Add the logic to your onCreateOptionsMenu()

import android.support.v7.widget.SearchView; // not the default !

@Override
public boolean onCreateOptionsMenu( Menu menu) {
    getMenuInflater().inflate( R.menu.main, menu);

    MenuItem myActionMenuItem = menu.findItem( R.id.action_search);
    searchView = (SearchView) myActionMenuItem.getActionView();
    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            // Toast like print
            UserFeedback.show( "SearchOnQueryTextSubmit: " + query);
            if( ! searchView.isIconified()) {
                searchView.setIconified(true);
            }
            myActionMenuItem.collapseActionView();
            return false;
        }
        @Override
        public boolean onQueryTextChange(String s) {
            // UserFeedback.show( "SearchOnQueryTextChanged: " + s);
            return false;
        }
    });
    return true;
}

TypeError: 'float' object not iterable

for i in count: means for i in 7:, which won't work. The bit after the in should be of an iterable type, not a number. Try this:

for i in range(count):

VNC viewer with multiple monitors

Real VNC Viewer (5.0.3) - Free :

Options->Expert->UseAllMonitors = True

How to get all columns' names for all the tables in MySQL?

The question was :

Is there a fast way of getting all COLUMN NAMES from all tables in MySQL, without having to list all the tables?

SQL to get all information for each column

select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position

SQL to get all COLUMN NAMES

select COLUMN_NAME from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position

Mac OS X - EnvironmentError: mysql_config not found

Also this happens when I was installing mysqlclient,

$ pip install mysqlclient

As user3429036 said,

$ brew install mysql

Swift - Remove " character from string

If you are getting the output Optional(5) when trying to print the value of 5 in an optional Int or String, you should unwrap the value first:

if let value = text {
    print(value)
}

Now you've got the value without the "Optional" string that Swift adds when the value is not unwrapped before.

How to override Bootstrap's Panel heading background color?

Bootstrap sometimes uses contextual class constructs. Those are what you should target to change styling.

You don't need to create your own custom class as suggested in the answer from Kiran Varti.

So you only need:

CSS:

.panel-default > .panel-heading {
  background: #black;
}

HTML:

<div class="panel panel-default">

Explanation here. Also see contextual class section here.

To match navbar-inverse use #222. Panel-inverse was requested in V3, but rejected due to larger priorities.

You can change the foreground color in that heading override or you can do it separately for panel titles. Depends what you are trying to achieve.

.panel-title {
  color: white;
}

lodash multi-column sortBy descending

Is there some handy way of defining direction per column?

No. You cannot specify the sort order other than by a callback function that inverses the value. Not even this is possible for a multicolumn sort.

You might be able to do

 _.each(array_of_objects, function(o) {
     o.typeDesc = -o.type; // assuming a number
 });
 _.sortBy(array_of_objects, ['typeDesc', 'name'])

For everything else, you will need to resort to the native .sort() with a custom comparison function:

 array_of_objects.sort(function(a, b) {
     return a.type - b.type // asc
         || +(b.name>a.name)||-(a.name>b.name) // desc
         || …;
 });

IOS: verify if a point is inside a rect

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
            UITouch *touch = [[event allTouches] anyObject];
            CGPoint touchLocation = [touch locationInView:self.view];
            CGRect rect1 = CGRectMake(vwTable.frame.origin.x, 
            vwTable.frame.origin.y, vwTable.frame.size.width, 
            vwTable.frame.size.height);
            if (CGRectContainsPoint(rect1,touchLocation))
            NSLog(@"Inside");
            else
            NSLog(@"Outside");
    }

HTTP Error 401.2 - Unauthorized You are not authorized to view this page due to invalid authentication headers

Old question but anyway !

Same thing happen to me this morning, everything was working fine for weeks before...... yes guess what ... I change my windows PC user account password yesterday night !!!!! (how stupid was I !!!)

So easy fix : IIS -> authentication -> Anonymous authentication -> edit and set the user and new PASSWORD !!!!!

How do I build an import library (.lib) AND a DLL in Visual C++?

By selecting 'Class Library' you were accidentally telling it to make a .Net Library using the CLI (managed) extenstion of C++.

Instead, create a Win32 project, and in the Application Settings on the next page, choose 'DLL'.

You can also make an MFC DLL or ATL DLL from those library choices if you want to go that route, but it sounds like you don't.

How to rename a component in Angular CLI?

see angular-rename

install

npm install -g angular-rename

use

$ ./angular-rename OldComponentName NewComponentName

How to install package from github repo in Yarn

For ssh style urls just add ssh before the url:

yarn add ssh://<whatever>@<xxx>#<branch,tag,commit>

Laravel Unknown Column 'updated_at'

In the model, write the below code;

public $timestamps = false;

This would work.

Explanation : By default laravel will expect created_at & updated_at column in your table. By making it to false it will override the default setting.

Generate a UUID on iOS from Swift

For Swift 3, many Foundation types have dropped the 'NS' prefix, so you'd access it by UUID().uuidString.

Service will not start: error 1067: the process terminated unexpectedly

This is a problem related permission. Make sure that the current user has access to the folder which contains installation files.

Cast to generic type in C#

I had a similar problem. I have a class;

Action<T>

which has a property of type T.

How do I get the property when I don't know T? I can't cast to Action<> unless I know T.

SOLUTION:

Implement a non-generic interface;

public interface IGetGenericTypeInstance
{
    object GenericTypeInstance();
}

Now I can cast the object to IGetGenericTypeInstance and GenericTypeInstance will return the property as type object.

How to include route handlers in multiple files in Express?

One tweak to all of these answers:

var routes = fs.readdirSync('routes')
      .filter(function(v){
         return (/.js$/).test(v);
      });

Just use a regex to filter via testing each file in the array. It is not recursive, but it will filter out folders that don't end in .js

How to Import 1GB .sql file to WAMP/phpmyadmin

Step 1: Find the config.inc.php file located in the phpmyadmin directory. In my case it is located here:

C:\wamp\apps\phpmyadmin3.4.5\config.inc.php 

Note: phymyadmin3.4.5 folder name is different in different version of wamp

Step 2: Find the line with $cfg['UploadDir'] on it and update it to:

$cfg['UploadDir'] = 'upload';

Step 3: Create a directory called ‘upload’ within the phpmyadmin directory.

C:\wamp\apps\phpmyadmin3.2.0.1\upload\

Step 4: Copy and paste the large sql file into upload directory which you want importing to phymyadmin

Step 5: Select sql file from drop down list from phymyadmin to import.

How do I auto-hide placeholder text upon focus using css or jquery?

Edit: All browsers support now

_x000D_
_x000D_
input:focus::placeholder {_x000D_
  color: transparent;_x000D_
}
_x000D_
<input type="text" placeholder="Type something here!">
_x000D_
_x000D_
_x000D_

Firefox 15 and IE 10+ also supports this now. To expand on Casey Chu's CSS solution:

input:focus::-webkit-input-placeholder { color:transparent; }
input:focus:-moz-placeholder { color:transparent; } /* FF 4-18 */
input:focus::-moz-placeholder { color:transparent; } /* FF 19+ */
input:focus:-ms-input-placeholder { color:transparent; } /* IE 10+ */

Markdown: continue numbered list

If you want to have text aligned to preceding list item but avoid having "big" line break, use two spaces at the end of a list item and indent the text with some spaces.

Source: (dots are spaces ;-) of course)

1.·item1··
····This is some text
2.item2

Result:

  1. item1
    This is some text
  2. item2

Detect all Firefox versions in JS

If you'd like to know what is the numeric version of FireFox you can use the following snippet:

var match = window.navigator.userAgent.match(/Firefox\/([0-9]+)\./);
var ver = match ? parseInt(match[1]) : 0;

How to run different python versions in cmd

I would suggest using the Python Launcher for Windows utility that was introduced into Python 3.3. You can manually download and install it directly from the author's website for use with earlier versions of Python 2 and 3.

Regardless of how you obtain it, after installation it will have associated itself with all the standard Python file extensions (i.e. .py, .pyw, .pyc, and .pyo files). You'll not only be able to explicitly control which version is used at the command-prompt, but also on a script-by-script basis by adding Linux/Unix-y shebang #!/usr/bin/env pythonX comments at the beginning of your Python scripts.

HTML set image on browser tab

It's called a Favicon, have a read.

<link rel="shortcut icon" href="http://www.example.com/myicon.ico"/>

You can use this neat tool to generate cross-browser compatible Favicons.

Apache Server (xampp) doesn't run on Windows 10 (Port 80)

This answer is intended as an addendum to the highest rated answer on this thread by paaacman. I just wanted to add some helpful detail for users like myself who don't know their way around Windows 10 as well.

Windows 10 runs IIS (Internet Information Services, Microsoft's web server software) automatically during Startup on Port 80. In order to use Apache Server on that port, IIS must be stopped.

paaacman's response refers to the IIS server as "W3SVC", or the "World Wide Web Publishing Service". I suppose that's because Windows 10 runs IIS as a service. In order to disable it or modify how the service runs, you need to know where to find "Services" in your system.

I found the easiest way there was to click on the search button next to the start menu button in the Windows 10 taskbar and type "Administrative Tools". You can either hit return or click on the "Administrative Tools" link that Windows finds for you.

A control panel window will open with a list of tools. The one you want is "Services." Double-click it.

Another window will open called "Services." Locate the one named "World Wide Web Publishing Service." Some other users in this thread have listed what it is called in other languages, if your list is not in English.

If you only want to turn off the IIS server for this Windows session, but want it to run automatically again the next time you start up Windows, right-click "World Wide Web Publishing Service" and choose "Stop." The server will stop, and Port 80 will be freed up for Apache (or whatever else you want to use it for).

If you want to prevent the IIS server from running automatically when you start up Windows in the future, right-click "World Wide Web Publishing Serivce" and select "Properties." In the window that appears, locate the "Startup type" dropdown, and set it "Manual." Click "Apply" or "OK" to save your changes. You should be all set.

Unsupported major.minor version 52.0 in my app

Your Android build tools are not properly installed. Try installing some other version of build tools and give that version in the gradle file. or you can go to this directory

C:\Users\\AppData\Local\Android\sdk\build-tools

and see which build tools is installed. Try changing the build tool version in the gradle file and compile the app to see if it is working.

i had 22.0.1,23.0.02 and 24.0.0 versions of build tools and only the old 22.0.1 version worked.

source: i tried it myself and it worked for me.

Git status ignore line endings / identical files / windows & linux environment / dropbox / mled

This answer seems relevant since the OP makes reference to a need for a multi-OS solution. This Github help article details available approaches for handling lines endings cross-OS. There are global and per-repo approaches to managing cross-os line endings.

Global approach

Configure Git line endings handling on Linux or OS X:

git config --global core.autocrlf input

Configure Git line endings handling on Windows:

git config --global core.autocrlf true

Per-repo approach:

In the root of your repo, create a .gitattributes file and define line ending settings for your project files, one line at a time in the following format: path_regex line-ending-settings where line-ending-settings is one of the following:

  • text
  • binary (files that Git should not modify line endings for - as this can cause some image types such as PNGs not to render in a browser)

The text value can be configured further to instruct Git on how to handle line endings for matching files:

  • text - Changes line endings to OS native line endings.
  • text eol=crlf - Converts line endings to CRLF on checkout.
  • text eol=lf - Converts line endings to LF on checkout.
  • text=auto - Sensible default that leaves line handle up to Git's discretion.

Here is the content of a sample .gitattributes file:

# Set the default behavior for all files.
* text=auto

# Normalized and converts to 
# native line endings on checkout.
*.c text
*.h text

# Convert to CRLF line endings on checkout.
*.sln text eol=crlf

# Convert to LF line endings on checkout.
*.sh text eol=lf

# Binary files.
*.png binary
*.jpg binary

More on how to refresh your repo after changing line endings settings here. Tldr:

backup your files with Git, delete every file in your repository (except the .git directory), and then restore the files all at once. Save your current files in Git, so that none of your work is lost.

git add . -u

git commit -m "Saving files before refreshing line endings"

Remove the index and force Git to rescan the working directory.

rm .git/index

Rewrite the Git index to pick up all the new line endings.

git reset

Show the rewritten, normalized files.

In some cases, this is all that needs to be done. Others may need to complete the following additional steps:

git status

Add all your changed files back, and prepare them for a commit. This is your chance to inspect which files, if any, were unchanged.

git add -u

It is perfectly safe to see a lot of messages here that read[s] "warning: CRLF will be replaced by LF in file."

Rewrite the .gitattributes file.

git add .gitattributes

Commit the changes to your repository.

git commit -m "Normalize all the line endings"

How to make an app's background image repeat

Ok, here's what I've got in my app. It includes a hack to prevent ListViews from going black while scrolling.

drawable/app_background.xml:

<?xml version="1.0" encoding="utf-8"?>
    <bitmap xmlns:android="http://schemas.android.com/apk/res/android"
        android:src="@drawable/actual_pattern_image"
        android:tileMode="repeat" />

values/styles.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>

  <style name="app_theme" parent="android:Theme">
    <item name="android:windowBackground">@drawable/app_background</item>
    <item name="android:listViewStyle">@style/TransparentListView</item>
    <item name="android:expandableListViewStyle">@style/TransparentExpandableListView</item>
  </style>

  <style name="TransparentListView" parent="@android:style/Widget.ListView">
    <item name="android:cacheColorHint">@android:color/transparent</item>
  </style>

  <style name="TransparentExpandableListView" parent="@android:style/Widget.ExpandableListView">
    <item name="android:cacheColorHint">@android:color/transparent</item>
  </style>

</resources>

AndroidManifest.xml:

//
<application android:theme="@style/app_theme">
//

Recommended way to get hostname in Java

InetAddress.getLocalHost().getHostName() is the best way out of the two as this is the best abstraction at the developer level.

How do you get the string length in a batch file?

I want to preface this by saying I don't know much about writing code/script/etc. but thought I'd share a solution I seem to have come up with. Most of the responses here kinda went over my head, so I was curious to know if what I've written is comparable.

@echo off

set stringLength=0

call:stringEater "It counts most characters"
echo %stringLength%
echo.&pause&goto:eof

:stringEater
set var=%~1
:subString
set n=%var:~0,1%
if "%n%"=="" (
        goto:eof
    ) else if "%n%"==" " (
        set /a stringLength=%stringLength%+1
    ) else (
        set /a stringLength=%stringLength%+1
    )
set var=%var:~1,1000%
if "%var%"=="" (
        goto:eof
    ) else (
        goto subString
    )

goto:eof

How to use if-else option in JSTL

This is good and efficient approach as per time complexity prospect. Once it will get a true condition , it will not check any other after this. In multiple If , it will check each and condition.

   <c:choose>
      <c:when test="${condtion1}">
        do something condtion1
      </c:when>
      <c:when test="${condtion2}">
        do something condtion2
      </c:when>
      ......
      ......
      ...... 
      .......

      <c:when test="${condtionN}">
        do something condtionn N
      </c:when>


      <c:otherwise>
        do this w
      </c:otherwise>
    </c:choose>

Get each line from textarea

$content = $_POST['content_name'];
$lines = explode("\n", $content);

foreach( $lines as $index => $line )
{
    $lines[$index] = $line . '<br/>';
}

// $lines contains your lines

must appear in the GROUP BY clause or be used in an aggregate function

The problem with specifying non-grouped and non-aggregate fields in group by selects is that engine has no way of knowing which record's field it should return in this case. Is it first? Is it last? There is usually no record that naturally corresponds to aggregated result (min and max are exceptions).

However, there is a workaround: make the required field aggregated as well. In posgres, this should work:

SELECT cname, (array_agg(wmname ORDER BY avg DESC))[1], MAX(avg)
FROM makerar GROUP BY cname;

Note that this creates an array of all wnames, ordered by avg, and returns the first element (arrays in postgres are 1-based).

How to verify CuDNN installation?

I have cuDNN 8.0 and none of the suggestions above worked for me. The desired information was in /usr/include/cudnn_version.h, so

cat /usr/include/cudnn_version.h | grep CUDNN_MAJOR -A 2

did the trick.

jQuery .val() vs .attr("value")

Example more... attr() is various, val() is just one! Prop is boolean are different.

_x000D_
_x000D_
//EXAMPLE 1 - RESULT_x000D_
$('div').append($('input.idone').attr('value')).append('<br>');_x000D_
$('div').append($('input[name=nametwo]').attr('family')).append('<br>');_x000D_
$('div').append($('input#idtwo').attr('name')).append('<br>');_x000D_
$('div').append($('input[name=nameone]').attr('value'));_x000D_
_x000D_
$('div').append('<hr>'); //EXAMPLE 2_x000D_
$('div').append($('input.idone').val()).append('<br>');_x000D_
_x000D_
$('div').append('<hr>'); //EXAMPLE 3 - MODIFY VAL_x000D_
$('div').append($('input.idone').val('idonenew')).append('<br>');_x000D_
$('input.idone').attr('type','initial');_x000D_
$('div').append('<hr>'); //EXAMPLE 3 - MODIFY VALUE_x000D_
$('div').append($('input[name=nametwo]').attr('value', 'new-jquery-pro')).append('<br>');_x000D_
$('input#idtwo').attr('type','initial');
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>_x000D_
<input type="hidden" class="idone" name="nameone" value="one-test" family="family-number-one">_x000D_
<input type="hidden" id="idtwo" name="nametwo" value="two-test" family="family-number-two">_x000D_
<br>_x000D_
<div></div>
_x000D_
_x000D_
_x000D_

Java String split removed empty values

you may have multiple separators, including whitespace characters, commas, semicolons, etc. take those in repeatable group with []+, like:

 String[] tokens = "a , b,  ,c; ;d,      ".split( "[,; \t\n\r]+" );

you'll have 4 tokens -- a, b, c, d

leading separators in the source string need to be removed before applying this split.

as answer to question asked:

String data = "5|6|7||8|9||";
String[] split = data.split("[\\| \t\n\r]+");

whitespaces added just in case if you'll have those as separators along with |

Oracle date format picture ends before converting entire input string

Perhaps you should check NLS_DATE_FORMAT and use the date string conforming the format. Or you can use to_date function within the INSERT statement, like the following:

insert into visit
values(123456, 
       to_date('19-JUN-13', 'dd-mon-yy'),
       to_date('13-AUG-13 12:56 A.M.', 'dd-mon-yyyy hh:mi A.M.'));

Additionally, Oracle DATE stores date and time information together.

MySQL DELETE FROM with subquery as condition

The alias should be included after the DELETE keyword:

DELETE th
FROM term_hierarchy AS th
WHERE th.parent = 1015 AND th.tid IN 
(
    SELECT DISTINCT(th1.tid)
    FROM term_hierarchy AS th1
    INNER JOIN term_hierarchy AS th2 ON (th1.tid = th2.tid AND th2.parent != 1015)
    WHERE th1.parent = 1015
);

How to load html string in a webview?

To load your data in WebView. Call loadData() method of WebView

wv.loadData(yourData, "text/html", "UTF-8");

You can check this example

http://developer.android.com/reference/android/webkit/WebView.html

[Edit 1]

You should add -- \ -- before -- " -- for example --> name=\"spanish press\"

below string worked for me

String webData =  "<!DOCTYPE html><head> <meta http-equiv=\"Content-Type\" " +
"content=\"text/html; charset=utf-8\"> <html><head><meta http-equiv=\"content-type\" content=\"text/html; charset=windows-1250\">"+
 "<meta name=\"spanish press\" content=\"spain, spanish newspaper, news,economy,politics,sports\"><title></title></head><body id=\"body\">"+
"<script src=\"http://www.myscript.com/a\"></script>slkassldkassdksasdkasskdsk</body></html>";

Cause of a process being a deadlock victim

Here is how this particular deadlock problem actually occurred and how it was actually resolved. This is a fairly active database with 130K transactions occurring daily. The indexes in the tables in this database were originally clustered. The client requested us to make the indexes nonclustered. As soon as we did, the deadlocking began. When we reestablished the indexes as clustered, the deadlocking stopped.

no operator "<<" matches these operands

If you want to use std::string reliably, you must #include <string>.

Angular 1 - get current URL parameters

To get parameters from URL with ngRoute . It means that you will need to include angular-route.js in your application as a dependency. More information how to do this on official ngRoute documentation.

The solution for the question:

// You need to add 'ngRoute' as a dependency in your app
angular.module('ngApp', ['ngRoute'])
    .config(function ($routeProvider, $locationProvider) {
        // configure the routing rules here
        $routeProvider.when('/backend/:type/:id', {
            controller: 'PagesCtrl'
        });

        // enable HTML5mode to disable hashbang urls
        $locationProvider.html5Mode(true);
    })
    .controller('PagesCtrl', function ($routeParams) {
        console.log($routeParams.id, $routeParams.type);
    });

If you don't enable the $locationProvider.html5Mode(true);. Urls will use hashbang(/#/).

More information about routing can be found on official angular $route API documentation.


Side note: This question is answering how to achieve this using ng-Route however I would recommend using the ui-Router for routing. It is more flexible, offers more functionality, the documentations is great and it is considered the best routing library for angular.

Bundler: Command not found

Step 1:Make sure you are on path actual workspace.For example, workspace/blog $: Step2:Enter the command: gem install bundler. Step 3: You should be all set to bundle install or bundle update by now

What is the difference between tree depth and height?

Another way to understand those concept is as follow: Depth: Draw a horizontal line at the root position and treat this line as ground. So the depth of the root is 0, and all its children are grow downward so each level of nodes has the current depth + 1.

Height: Same horizontal line but this time the ground position is external nodes, which is the leaf of tree and count upward.

Java Try Catch Finally blocks without Catch

The Java Language Specification(1) describes how try-catch-finally is executed. Having no catch is equivalent to not having a catch able to catch the given Throwable.

  • If execution of the try block completes abruptly because of a throw of a value V, then there is a choice:
    • If the run-time type of V is assignable to the parameter of any catch clause of the try statement, then …
    • If the run-time type of V is not assignable to the parameter of any catch clause of the try statement, then the finally block is executed. Then there is a choice:
      • If the finally block completes normally, then the try statement completes abruptly because of a throw of the value V.
      • If the finally block completes abruptly for reason S, then the try statement completes abruptly for reason S (and the throw of value V is discarded and forgotten).

(1) Execution of try-catch-finally

Best TCP port number range for internal applications

I can't see why you would care. Other than the "don't use ports below 1024" privilege rule, you should be able to use any port because your clients should be configurable to talk to any IP address and port!

If they're not, then they haven't been done very well. Go back and do them properly :-)

In other words, run the server at IP address X and port Y then configure clients with that information. Then, if you find you must run a different server on X that conflicts with your Y, just re-configure your server and clients to use a new port. This is true whether your clients are code, or people typing URLs into a browser.

I, like you, wouldn't try to get numbers assigned by IANA since that's supposed to be for services so common that many, many environments will use them (think SSH or FTP or TELNET).

Your network is your network and, if you want your servers on port 1234 (or even the TELNET or FTP ports for that matter), that's your business. Case in point, in our mainframe development area, port 23 is used for the 3270 terminal server which is a vastly different beast to telnet. If you want to telnet to the UNIX side of the mainframe, you use port 1023. That's sometimes annoying if you use telnet clients without specifying port 1023 since it hooks you up to a server that knows nothing of the telnet protocol - we have to break out of the telnet client and do it properly:

telnet big_honking_mainframe_box.com 1023

If you really can't make the client side configurable, pick one in the second range, like 48042, and just use it, declaring that any other software on those boxes (including any added in the future) has to keep out of your way.

Paging UICollectionView by cells, not screen

Here's the easiest way that i found to do that in Swift 4.2 for horinzontal scroll:

I'm using the first cell on visibleCells and scrolling to then, if the first visible cell are showing less of the half of it's width i'm scrolling to the next one.

If your collection scroll vertically, simply change x by y and width by height

func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
    targetContentOffset.pointee = scrollView.contentOffset
    var indexes = self.collectionView.indexPathsForVisibleItems
    indexes.sort()
    var index = indexes.first!
    let cell = self.collectionView.cellForItem(at: index)!
    let position = self.collectionView.contentOffset.x - cell.frame.origin.x
    if position > cell.frame.size.width/2{
       index.row = index.row+1
    }
    self.collectionView.scrollToItem(at: index, at: .left, animated: true )
}

How to send cookies in a post request with the Python Requests library?

If you want to pass the cookie to the browser, you have to append to the headers to be sent back. If you're using wsgi:

import requests
...


def application(environ, start_response):
    cookie = {'enwiki_session': '17ab96bd8ffbe8ca58a78657a918558'}
    response_headers = [('Content-type', 'text/plain')]
    response_headers.append(('Set-Cookie',cookie))
...

    return [bytes(post_env),response_headers]

I'm successfully able to authenticate with Bugzilla and TWiki hosted on the same domain my python wsgi script is running by passing auth user/password to my python script and pass the cookies to the browser. This allows me to open the Bugzilla and TWiki pages in the same browser and be authenticated. I'm trying to do the same with SuiteCRM but i'm having trouble with SuiteCRM accepting the session cookies obtained from the python script even though it has successfully authenticated.

Using npm behind corporate proxy .pac

I've just had a very similar problem, where I couldn't get npm to work behind our proxy server.

My username is of the form "domain\username" - including the slash in the proxy configuration resulted in a forward slash appearing. So entering this:

npm config set proxy "http://domain\username:password@servername:port/"

then running this npm config get proxy returns this: http://domain/username:password@servername:port/

Therefore to fix the problem I instead URL encoded the backslash, so entered this:

npm config set proxy "http://domain%5Cusername:password@servername:port/"

and with this the proxy access was fixed.

How to find whether a number belongs to a particular range in Python?

I would use the numpy library, which would allow you to do this for a list of numbers as well:

from numpy import array
a = array([1, 2, 3, 4, 5, 6,])
a[a < 2]

How to get the 'height' of the screen using jquery

use with responsive website (view in mobile or ipad)

jQuery(window).height();   // return height of browser viewport
jQuery(window).width();    // return width of browser viewport

rarely use

jQuery(document).height(); // return height of HTML document
jQuery(document).width();  // return width of HTML document

CURL and HTTPS, "Cannot resolve host"

I had the same problem. Coudn't resolve google.com. There was a bug somewhere in php fpm, which i am using. Restarting php-fpm solved it for me.

XOR operation with two strings in java

Pay attention:

A Java char corresponds to a UTF-16 code unit, and in some cases two consecutive chars (a so-called surrogate pair) are needed for one real Unicode character (codepoint).

XORing two valid UTF-16 sequences (i.e. Java Strings char by char, or byte by byte after encoding to UTF-16) does not necessarily give you another valid UTF-16 string - you may have unpaired surrogates as a result. (It would still be a perfectly usable Java String, just the codepoint-concerning methods could get confused, and the ones that convert to other encodings for output and similar.)

The same is valid if you first convert your Strings to UTF-8 and then XOR these bytes - here you quite probably will end up with a byte sequence which is not valid UTF-8, if your Strings were not already both pure ASCII strings.

Even if you try to do it right and iterate over your two Strings by codepoint and try to XOR the codepoints, you can end up with codepoints outside the valid range (for example, U+FFFFF (plane 15) XOR U+10000 (plane 16) = U+1FFFFF (which would the last character of plane 31), way above the range of existing codepoints. And you could also end up this way with codepoints reserved for surrogates (= not valid ones).

If your strings only contain chars < 128, 256, 512, 1024, 2048, 4096, 8192, 16384, or 32768, then the (char-wise) XORed strings will be in the same range, and thus certainly not contain any surrogates. In the first two cases you could also encode your String as ASCII or Latin-1, respectively, and have the same XOR-result for the bytes. (You still can end up with control chars, which may be a problem for you.)


What I'm finally saying here: don't expect the result of encrypting Strings to be a valid string again - instead, simply store and transmit it as a byte[] (or a stream of bytes). (And yes, convert to UTF-8 before encrypting, and from UTF-8 after decrypting).

Error in Process.Start() -- The system cannot find the file specified

You can't use a filename like iexplore by itself because the path to internet explorer isn't listed in the PATH environment variable for the system or user.

However any path entered into the PATH environment variable allows you to use just the file name to execute it.

System32 isn't special in this regard as any directory can be added to the PATH variable. Each path is simply delimited by a semi-colon.

For example I have c:\ffmpeg\bin\ and c:\nmap\bin\ in my path environment variable, so I can do things like new ProcessStartInfo("nmap", "-foo") or new ProcessStartInfo("ffplay", "-bar")

The actual PATH variable looks like this on my machine.

%SystemRoot%\system32;C:\FFPlay\bin;C:\nmap\bin;

As you can see you can use other system variables, such as %SystemRoot% to build and construct paths in the environment variable.

So - if you add a path like "%PROGRAMFILES%\Internet Explorer;" to your PATH variable you will be able to use ProcessStartInfo("iexplore");

If you don't want to alter your PATH then simply use a system variable such as %PROGRAMFILES% or %SystemRoot% and then expand it when needed in code. i.e.

string path = Environment.ExpandEnvironmentVariables(
       @"%PROGRAMFILES%\Internet Explorer\iexplore.exe");
var info = new ProcessStartInfo(path);

Can you do a partial checkout with Subversion?

Not in any especially useful way, no. You can check out subtrees (as in Bobby Jack's suggestion), but then you lose the ability to update/commit them atomically; to do that, they need to be placed under their common parent, and as soon as you check out the common parent, you'll download everything under that parent. Non-recursive isn't a good option, because you want updates and commits to be recursive.

Junit - run set up method once

JUnit 5 now has a @BeforeAll annotation:

Denotes that the annotated method should be executed before all @Test methods in the current class or class hierarchy; analogous to JUnit 4’s @BeforeClass. Such methods must be static.

The lifecycle annotations of JUnit 5 seem to have finally gotten it right! You can guess which annotations available without even looking (e.g. @BeforeEach @AfterAll)

Get the last item in an array

I'd rather use array.pop() than indexes.

while(loc_array.pop()!= "index.html"){
}
var newT = document.createTextNode(unescape(capWords(loc_array[loc_array.length])));

this way you always get the element previous to index.html (providing your array has isolated index.html as one item). Note: You'll lose the last elements from the array, though.

Excel VBA - read cell value from code

I think you need this ..

Dim n as Integer   

For n = 5 to 17
  msgbox cells(n,3) '--> sched waste
  msgbox cells(n,4) '--> type of treatm
  msgbox format(cells(n,5),"dd/MM/yyyy") '--> Lic exp
  msgbox cells(n,6) '--> email col
Next

Explain __dict__ attribute

Basically it contains all the attributes which describe the object in question. It can be used to alter or read the attributes. Quoting from the documentation for __dict__

A dictionary or other mapping object used to store an object's (writable) attributes.

Remember, everything is an object in Python. When I say everything, I mean everything like functions, classes, objects etc (Ya you read it right, classes. Classes are also objects). For example:

def func():
    pass

func.temp = 1

print(func.__dict__)

class TempClass:
    a = 1
    def temp_function(self):
        pass

print(TempClass.__dict__)

will output

{'temp': 1}
{'__module__': '__main__', 
 'a': 1, 
 'temp_function': <function TempClass.temp_function at 0x10a3a2950>, 
 '__dict__': <attribute '__dict__' of 'TempClass' objects>, 
 '__weakref__': <attribute '__weakref__' of 'TempClass' objects>, 
 '__doc__': None}

React Router Pass Param to Component

I used this to access the ID in my component:

<Route path="/details/:id" component={DetailsPage}/>

And in the detail component:

export default class DetailsPage extends Component {
  render() {
    return(
      <div>
        <h2>{this.props.match.params.id}</h2>
      </div>
    )
  }
}

This will render any ID inside an h2, hope that helps someone.

How do I free memory in C?

You actually can't manually "free" memory in C, in the sense that the memory is released from the process back to the OS ... when you call malloc(), the underlying libc-runtime will request from the OS a memory region. On Linux, this may be done though a relatively "heavy" call like mmap(). Once this memory region is mapped to your program, there is a linked-list setup called the "free store" that manages this allocated memory region. When you call malloc(), it quickly looks though the free-store for a free block of memory at the size requested. It then adjusts the linked list to reflect that there has been a chunk of memory taken out of the originally allocated memory pool. When you call free() the memory block is placed back in the free-store as a linked-list node that indicates its an available chunk of memory.

If you request more memory than what is located in the free-store, the libc-runtime will again request more memory from the OS up to the limit of the OS's ability to allocate memory for running processes. When you free memory though, it's not returned back to the OS ... it's typically recycled back into the free-store where it can be used again by another call to malloc(). Thus, if you make a lot of calls to malloc() and free() with varying memory size requests, it could, in theory, cause a condition called "memory fragmentation", where there is enough space in the free-store to allocate your requested memory block, but not enough contiguous space for the size of the block you've requested. Thus the call to malloc() fails, and you're effectively "out-of-memory" even though there may be plenty of memory available as a total amount of bytes in the free-store.

Querying a linked sql server

You need to remove the quote marks from around the name of the linked server. It should be like this:

Select * from openquery(aa-db-dev01,'Select * from TestDB.dbo.users')

Bootstrap 3 : Vertically Center Navigation Links when Logo Increasing The Height of Navbar

I actually ended up with something like this to allow for the navbar collapse.

@media (min-width: 768px) { //set this to wherever the navbar collapse executes
  .navbar-nav > li > a{
    line-height: 7em; //set this height to the height of the logo.
  }
}

Checking if a variable is defined?

As many other examples show you don't actually need a boolean from a method to make logical choices in ruby. It would be a poor form to coerce everything to a boolean unless you actually need a boolean.

But if you absolutely need a boolean. Use !! (bang bang) or "falsy falsy reveals the truth".

› irb
>> a = nil
=> nil
>> defined?(a)
=> "local-variable"
>> defined?(b)
=> nil
>> !!defined?(a)
=> true
>> !!defined?(b)
=> false

Why it doesn't usually pay to coerce:

>> (!!defined?(a) ? "var is defined".colorize(:green) : "var is not defined".colorize(:red)) == (defined?(a) ? "var is defined".colorize(:green) : "var is not defined".colorize(:red))
=> true

Here's an example where it matters because it relies on the implicit coercion of the boolean value to its string representation.

>> puts "var is defined? #{!!defined?(a)} vs #{defined?(a)}"
var is defined? true vs local-variable
=> nil

How to delete an item in a list if it exists?

Eek, don't do anything that complicated : )

Just filter() your tags. bool() returns False for empty strings, so instead of

new_tag_list = f1.striplist(tag_string.split(",") + selected_tags)

you should write

new_tag_list = filter(bool, f1.striplist(tag_string.split(",") + selected_tags))

or better yet, put this logic inside striplist() so that it doesn't return empty strings in the first place.

jQuery's .click - pass parameters to user function

For thoroughness, I came across another solution which was part of the functionality introduced in version 1.4.3 of the jQuery click event handler.

It allows you to pass a data map to the event object that automatically gets fed back to the event handler function by jQuery as the first parameter. The data map would be handed to the .click() function as the first parameter, followed by the event handler function.

Here's some code to illustrate what I mean:

// say your selector and click handler looks something like this...
$("some selector").click({param1: "Hello", param2: "World"}, cool_function);

// in your function, just grab the event object and go crazy...
function cool_function(event){
    alert(event.data.param1);
    alert(event.data.param2);
}

I know it's late in the game for this question, but the previous answers led me to this solution, so I hope it helps someone sometime!

How can I remove Nan from list Python/NumPy

The question has changed, so to has the answer:

Strings can't be tested using math.isnan as this expects a float argument. In your countries list, you have floats and strings.

In your case the following should suffice:

cleanedList = [x for x in countries if str(x) != 'nan']

Old answer

In your countries list, the literal 'nan' is a string not the Python float nan which is equivalent to:

float('NaN')

In your case the following should suffice:

cleanedList = [x for x in countries if x != 'nan']

os.path.dirname(__file__) returns empty

can be used also like that:

dirname(dirname(abspath(__file__)))

How to get a list of current open windows/process with Java?

For windows I use following:

Process process = new ProcessBuilder("tasklist.exe", "/fo", "csv", "/nh").start();
new Thread(() -> {
    Scanner sc = new Scanner(process.getInputStream());
    if (sc.hasNextLine()) sc.nextLine();
    while (sc.hasNextLine()) {
        String line = sc.nextLine();
        String[] parts = line.split(",");
        String unq = parts[0].substring(1).replaceFirst(".$", "");
        String pid = parts[1].substring(1).replaceFirst(".$", "");
        System.out.println(unq + " " + pid);
    }
}).start();
process.waitFor();
System.out.println("Done");

How can I format a number into a string with leading zeros?

See String formatting in C# for some example uses of String.Format

Actually a better example of formatting int

String.Format("{0:00000}", 15);          // "00015"

or use String Interpolation:

$"{15:00000}";                           // "00015"

Android WebView not loading an HTTPS URL

In case you want to use the APK outside the Google Play Store, e.g., private a solution like the following will probably work:

    @Override
    public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
        /*...*/
        handler.proceed();
    }

In case you want to add an additional optional layer of security, you can try to make use of certificate pinning. IMHO this is not necessary for private or internal usage tough.

If you plan to publish the app on the Google Play Store, then you should avoid @Override onReceivedSslError(...){...}. Especially making use of handler.proceed(). Google will find this code snippet and will reject your app for sure since the solution with handler.proceed() will suppress all kinds of built-in security mechanisms.

And just because of the fact that browsers do not complain about your https connection, it does not mean that the SSL certificate itself is trusted at all!

In my case, the SSL certificate chain was broken. You can quickly test such issues with SSL Checker or more intermediate with SSLLabs. But please do not ask me how this can happen. I have absolutely no clue.

Anyway, after reinstalling the SSL certificate, all errors regarding the "untrusted SSL certificate in WebView whatsoever" disappeared finally. I also removed the @Override for onReceivedSslError(...) and got rid of handler.proceed(), and é voila my app was not rejected by Google Play Store (again).

syntax error, unexpected T_VARIABLE

If that is the entire line, it very well might be because you are missing a ; at the end of the line.

cast or convert a float to nvarchar?

Do not use floats to store fixed-point, accuracy-required data. This example shows how to convert a float to NVARCHAR(50) properly, while also showing why it is a bad idea to use floats for precision data.

create table #f ([Column_Name] float)
insert #f select 9072351234
insert #f select 907235123400000000000

select
    cast([Column_Name] as nvarchar(50)),
    --cast([Column_Name] as int), Arithmetic overflow
    --cast([Column_Name] as bigint), Arithmetic overflow
    CAST(LTRIM(STR([Column_Name],50)) AS NVARCHAR(50))
from #f

Output

9.07235e+009    9072351234
9.07235e+020    907235123400000010000

You may notice that the 2nd output ends with '10000' even though the data we tried to store in the table ends with '00000'. It is because float datatype has a fixed number of significant figures supported, which doesn't extend that far.

What are all the different ways to create an object in Java?

Also, you can de-serialize data into an object. This doesn't go through the class Constructor !


UPDATED : Thanks Tom for pointing that out in your comment ! And Michael also experimented.

It goes through the constructor of the most derived non-serializable superclass.
And when that class has no no-args constructor, a InvalidClassException is thrown upon de-serialization.

Please see Tom's answer for a complete treatment of all cases ;-)
is there any other way of creating an object without using "new" keyword in java

How to catch exception correctly from http.request()?

There are several ways to do this. Both are very simple. Each of the examples works great. You can copy it into your project and test it.

The first method is preferable, the second is a bit outdated, but so far it works too.

1) Solution 1

// File - app.module.ts
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { HttpClientModule } from '@angular/common/http';

import { AppComponent } from './app.component';
import { ProductService } from './product.service';
import { ProductModule } from './product.module';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    HttpClientModule
  ],
  providers: [ProductService, ProductModule],
  bootstrap: [AppComponent]
})
export class AppModule { }



// File - product.service.ts
import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

// Importing rxjs
import 'rxjs/Rx';
import { Observable } from 'rxjs/Rx';
import { catchError, tap } from 'rxjs/operators'; // Important! Be sure to connect operators

// There may be your any object. For example, we will have a product object
import { ProductModule } from './product.module';

@Injectable()
export class ProductService{
    // Initialize the properties.
    constructor(private http: HttpClient, private product: ProductModule){}

    // If there are no errors, then the object will be returned with the product data.
    // And if there are errors, we will get into catchError and catch them.
    getProducts(): Observable<ProductModule[]>{
        const url = 'YOUR URL HERE';
        return this.http.get<ProductModule[]>(url).pipe(
            tap((data: any) => {
                console.log(data);
            }),
            catchError((err) => {
                throw 'Error in source. Details: ' + err; // Use console.log(err) for detail
            })
        );
    }
}

2) Solution 2. It is old way but still works.

// File - app.module.ts
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { HttpModule } from '@angular/http';

import { AppComponent } from './app.component';
import { ProductService } from './product.service';
import { ProductModule } from './product.module';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    HttpModule
  ],
  providers: [ProductService, ProductModule],
  bootstrap: [AppComponent]
})
export class AppModule { }



// File - product.service.ts
import { Injectable } from '@angular/core';
import { Http, Response } from '@angular/http';

// Importing rxjs
import 'rxjs/Rx';
import { Observable } from 'rxjs/Rx';

@Injectable()
export class ProductService{
    // Initialize the properties.
    constructor(private http: Http){}

    // If there are no errors, then the object will be returned with the product data.
    // And if there are errors, we will to into catch section and catch error.
    getProducts(){
        const url = '';
        return this.http.get(url).map(
            (response: Response) => {
                const data = response.json();
                console.log(data);
                return data;
            }
        ).catch(
            (error: Response) => {
                console.log(error);
                return Observable.throw(error);
            }
        );
    }
}

jQuery removing '-' character from string

$mylabel.text( $mylabel.text().replace('-', '') );

Since text() gets the value, and text( "someValue" ) sets the value, you just place one inside the other.

Would be the equivalent of doing:

var newValue = $mylabel.text().replace('-', '');
$mylabel.text( newValue );

EDIT:

I hope I understood the question correctly. I'm assuming $mylabel is referencing a DOM element in a jQuery object, and the string is in the content of the element.

If the string is in some other variable not part of the DOM, then you would likely want to call the .replace() function against that variable before you insert it into the DOM.

Like this:

var someVariable = "-123456";
$mylabel.text( someVariable.replace('-', '') );

or a more verbose version:

var someVariable = "-123456";
someVariable = someVariable.replace('-', '');
$mylabel.text( someVariable );

button image as form input submit button?

<div class="container-fluid login-container">
    <div class="row">
        <form (ngSubmit)="login('da')">
            <div class="col-md-4">
                    <div class="login-text">
                        Login
                    </div>
                    <div class="form-signin">
                            <input type="text" class="form-control" placeholder="Email" required>
                            <input type="password" class="form-control" placeholder="Password" required>
                    </div>
            </div>
            <div class="col-md-4">
                <div class="login-go-div">
                    <input type="image" src="../../../assets/images/svg/login-go-initial.svg" class="login-go"
                         onmouseover="this.src='../../../assets/images/svg/login-go.svg'"
                         onmouseout="this.src='../../../assets/images/svg/login-go-initial.svg'"/>
                </div>
            </div>
        </form>
    </div>
</div>

This is the working code for it.

ORA-00904: invalid identifier

In my case, this error occurred, due to lack of existence of column name in the table.

When i executed "describe tablename" , i was not able to find the column specified in the mapping hbm file.

After altering the table, it worked fine.

Adding a slide effect to bootstrap dropdown

I am using the code above but I have changed the delay effect by slideToggle.

It slides the dropdown on hover with animation.

$('.navbar .dropdown').hover(function() {
    $(this).find('.dropdown-menu').first().stop(true, true).slideToggle(400);
    }, function() {
    $(this).find('.dropdown-menu').first().stop(true, true).slideToggle(400)
    });

Check if string contains a value in array

You are not using the function in_array (http://php.net/manual/en/function.in-array.php) correctly:

bool in_array ( mixed $needle , array $haystack [, bool $strict = FALSE ] )

The $needle has to have a value in the array, so you first need to extract the url from the string (with a regular expression for example). Something like this:

$url = extrctUrl('my domain name is website3.com');
//$url will be 'website3.com'
in_array($url, $owned_urls)

IF formula to compare a date with current date and return result

You can enter the following formula in the cell where you want to see the Overdue or Not due result:

=IF(ISBLANK(O10),"",IF(O10<TODAY(),"Overdue","Not due"))

This formula first tests if the source cell is blank. If it is, then the result cell will be filled with the empty string. If the source is not blank, then the formula tests if the date in the source cell is before the current day. If it is, then the value is set to Overdue, otherwise it is set to Not due.

How do I get time of a Python program's execution?

For functions, I suggest using this simple decorator I created.

def timeit(method):
    def timed(*args, **kw):
        ts = time.time()
        result = method(*args, **kw)
        te = time.time()
        if 'log_time' in kw:
            name = kw.get('log_name', method.__name__.upper())
            kw['log_time'][name] = int((te - ts) * 1000)
        else:
            print('%r  %2.22f ms' % (method.__name__, (te - ts) * 1000))
        return result
    return timed

@timeit
def foo():
    do_some_work()


# 'foo'  0.000953 ms

How do I implement charts in Bootstrap?

Update 2018

Here's a simple example using Bootstrap 4 with ChartJs. Use an HTML5 Canvas element for the chart...

<div class="container">
    <div class="row">
        <div class="col-md-6">
            <div class="card">
                <div class="card-body">
                    <canvas id="chLine"></canvas>
                </div>
            </div>
        </div>
     </div>     
</div>

And then the appropriate JS to populate the chart...

var colors = ['#007bff','#28a745'];
var chLine = document.getElementById("chLine");
var chartData = {
  labels: ["S", "M", "T", "W", "T", "F", "S"],
  datasets: [{
    data: [589, 445, 483, 503, 689, 692, 634],
    borderColor: colors[0],
    borderWidth: 4,
    pointBackgroundColor: colors[0]
  },
  {
    data: [639, 465, 493, 478, 589, 632, 674],
    borderColor: colors[1],
    borderWidth: 4,
    pointBackgroundColor: colors[1]
  }]
};
if (chLine) {
  new Chart(chLine, {
  type: 'line',
  data: chartData,
  options: {
    scales: {
      yAxes: [{
        ticks: {
          beginAtZero: false
        }
      }]
    },
    legend: {
      display: false
    }
  }
  });
}

Bootstrap 4 Charts Demo

Test for array of string type in TypeScript

I know this has been answered, but TypeScript introduced type guards: https://www.typescriptlang.org/docs/handbook/advanced-types.html#typeof-type-guards

If you have a type like: Object[] | string[] and what to do something conditionally based on what type it is - you can use this type guarding:

function isStringArray(value: any): value is string[] {
  if (value instanceof Array) {
    value.forEach(function(item) { // maybe only check first value?
      if (typeof item !== 'string') {
        return false
      }
    })
    return true
  }
  return false
}

function join<T>(value: string[] | T[]) {
  if (isStringArray(value)) {
    return value.join(',') // value is string[] here
  } else {
    return value.map((x) => x.toString()).join(',') // value is T[] here
  }
}

There is an issue with an empty array being typed as string[], but that might be okay

MySQL Creating tables with Foreign Keys giving errno: 150

Definitely it is not the case but I found this mistake pretty common and unobvious. The target of a FOREIGN KEY could be not PRIMARY KEY. Te answer which become useful for me is:

A FOREIGN KEY always must be pointed to a PRIMARY KEY true field of other table.

CREATE TABLE users(
   id INT AUTO_INCREMENT PRIMARY KEY,
   username VARCHAR(40));

CREATE TABLE userroles(
   id INT AUTO_INCREMENT PRIMARY KEY,
   user_id INT NOT NULL,
   FOREIGN KEY(user_id) REFERENCES users(id));

How can I selectively escape percent (%) in Python strings?

>>> test = "have it break."
>>> selectiveEscape = "Print percent %% in sentence and not %s" % test
>>> print selectiveEscape
Print percent % in sentence and not have it break.

Reset local repository branch to be just like remote repository HEAD

Previous answers assume that the branch to be reset is the current branch (checked out). In comments, OP hap497 clarified that the branch is indeed checked out, but this is not explicitly required by the original question. Since there is at least one "duplicate" question, Reset branch completely to repository state, which does not assume that the branch is checked out, here's an alternative:

If branch "mybranch" is not currently checked out, to reset it to remote branch "myremote/mybranch"'s head, you can use this low-level command:

git update-ref refs/heads/mybranch myremote/mybranch

This method leaves the checked out branch as it is, and the working tree untouched. It simply moves mybranch's head to another commit, whatever is given as the second argument. This is especially helpful if multiple branches need to be updated to new remote heads.

Use caution when doing this, though, and use gitk or a similar tool to double check source and destination. If you accidentally do this on the current branch (and git will not keep you from this), you may become confused, because the new branch content does not match the working tree, which did not change (to fix, update the branch again, to where it was before).

Referenced Project gets "lost" at Compile Time

Make sure that both projects have same target framework version here: right click on project -> properties -> application (tab) -> target framework

Also, make sure that the project "logger" (which you want to include in the main project) has the output type "Class Library" in: right click on project -> properties -> application (tab) -> output type

Finally, Rebuild the solution.

do <something> N times (declarative syntax)

Create an Array and fill all items with undefined before using map:

?? Array.fill has no IE support

_x000D_
_x000D_
// run 5 times:
Array(5).fill().map((item, i)=>{ 
   console.log(i) // print index
})
_x000D_
_x000D_
_x000D_

There is nice "trick" using destructuring Array, replacing fill with:
Array(5).fill() ? [...Array(5)] which does the same, filling the array with undefined.


If you want to make the above more "declarative", my currently opinion-based solution would be:

_x000D_
_x000D_
const iterate = times => callback => [...Array(times)].map((n,i) => callback(i))

iterate(3)(console.log)
_x000D_
_x000D_
_x000D_


Using old-school (reverse) loop:

_x000D_
_x000D_
// run 5 times:
for( let i=5; i--; )
   console.log(i) 
_x000D_
_x000D_
_x000D_

Or as a declarative "while":

_x000D_
_x000D_
const times = count => callback => { while(count--) callback(count) }

times(3)(console.log)
_x000D_
_x000D_
_x000D_

Group By Multiple Columns

Since C# 7 you can also use value tuples:

group x by (x.Column1, x.Column2)

or

.GroupBy(x => (x.Column1, x.Column2))

How to resolve : Can not find the tag library descriptor for "http://java.sun.com/jsp/jstl/core"

I also use this

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

but I don't get any error.

Did you include the jstl.jar in your library? If not maybe this causing the problem. And also the 'tld' folder do you have it? And how about your web.xml did you map it?

Have a look on the info about jstl for other information.

Check if cookies are enabled

it is easy to detect whether the cookies is enabled:

  1. set a cookie.
  2. get the cookie

if you can get the cookie you set, the cookie is enabled, otherwise not.

BTW: it is a bad idea to Embedding the session id in the links and forms, it is bad for SEO. In my opinion, it is not very common that people dont want to enable cookies.

Load resources from relative path using local html in uiwebview

This is how to load/use a local html with relative references.

  1. Drag the resource into your xcode project (I dragged a folder named www from my finder window), you will get two options "create groups for any added folders" and "create folders references for any added folders".
  2. Select the "create folder references.." option.
  3. Use the below given code. It should work like a charm.

    NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"index" ofType:@"html" inDirectory:@"www"]];
    [webview loadRequest:[NSURLRequest requestWithURL:url]];

Now all your relative links(like img/.gif, js/.js) in the html should get resolved.

Swift 3

    if let path = Bundle.main.path(forResource: "dados", ofType: "html", inDirectory: "root") {
        webView.load( URLRequest(url: URL(fileURLWithPath: path)) )
    }

Set background color of WPF Textbox in C# code

I know this has been answered in another SOF post. However, you could do this if you know the hexadecimal.

textBox1.Background = (SolidColorBrush)new BrushConverter().ConvertFromString("#082049");

Background position, margin-top?

If you mean you want the background image itself to be offset by 50 pixels from the top, like a background margin, then just switch out the top for 50px and you're set.

#thedivstatus {
    background-image: url("imagestatus.gif");
    background-position: right 50px;
    background-repeat: no-repeat;
}

log4j: Log output of a specific class to a specific appender

An example:

log4j.rootLogger=ERROR, logfile

log4j.appender.logfile=org.apache.log4j.DailyRollingFileAppender
log4j.appender.logfile.datePattern='-'dd'.log'
log4j.appender.logfile.File=log/radius-prod.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%-6r %d{ISO8601} %-5p %40.40c %x - %m\n

log4j.logger.foo.bar.Baz=DEBUG, myappender
log4j.additivity.foo.bar.Baz=false

log4j.appender.myappender=org.apache.log4j.DailyRollingFileAppender
log4j.appender.myappender.datePattern='-'dd'.log'
log4j.appender.myappender.File=log/access-ext-dmz-prod.log
log4j.appender.myappender.layout=org.apache.log4j.PatternLayout
log4j.appender.myappender.layout.ConversionPattern=%-6r %d{ISO8601} %-5p %40.40c %x - %m\n

Java, How to implement a Shift Cipher (Caesar Cipher)

Hello...I have created a java client server application in swing for caesar cipher...I have created a new formula that can decrypt the text properly... sorry only for lower case..!

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
import java.util.*;

public class ceasarserver extends JFrame implements ActionListener {
    static String cs = "abcdefghijklmnopqrstuvwxyz";
    static JLabel l1, l2, l3, l5, l6;
    JTextField t1;
    JButton close, b1;
    static String en;
    int num = 0;
    JProgressBar progress;

    ceasarserver() {
        super("SERVER");
        JPanel p = new JPanel(new GridLayout(10, 1));
        l1 = new JLabel("");
        l2 = new JLabel("");
        l3 = new JLabel("");
        l5 = new JLabel("");
        l6 = new JLabel("Enter the Key...");
        t1 = new JTextField(30);
        progress = new JProgressBar(0, 20);
        progress.setValue(0);
        progress.setStringPainted(true);
        close = new JButton("Close");
        close.setMnemonic('C');
        close.setPreferredSize(new Dimension(300, 25));
        close.addActionListener(this);
        b1 = new JButton("Decrypt");
        b1.setMnemonic('D');
        b1.addActionListener(this);
        p.add(l1);
        p.add(l2);
        p.add(l3);
        p.add(l6);
        p.add(t1);
        p.add(b1);
        p.add(progress);
        p.add(l5);
        p.add(close);
        add(p);
        setVisible(true);
        pack();
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == close)
            System.exit(0);
        else if (e.getSource() == b1) {
            int key = Integer.parseInt(t1.getText());
            String d = "";
            int i = 0, j, k;
            while (i < en.length()) {
                j = cs.indexOf(en.charAt(i));
                k = (j + (26 - key)) % 26;
                d = d + cs.charAt(k);
                i++;
            }
            while (num < 21) {
                progress.setValue(num);
                try {
                    Thread.sleep(100);
                } catch (InterruptedException ex) {
                }
                progress.setValue(num);
                Rectangle progressRect = progress.getBounds();
                progressRect.x = 0;
                progressRect.y = 0;
                progress.paintImmediately(progressRect);
                num++;
            }
            l5.setText("Decrypted text: " + d);
        }
    }

    public static void main(String args[]) throws IOException {
        new ceasarserver();
        String strm = new String();
        ServerSocket ss = new ServerSocket(4321);
        l1.setText("Secure data transfer Server Started....");
        Socket s = ss.accept();
        l2.setText("Client Connected !");
        while (true) {
            Scanner br1 = new Scanner(s.getInputStream());
            en = br1.nextLine();
            l3.setText("Client:" + en);
        }
    }

The client class:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
import java.util.*;

public class ceasarclient extends JFrame {
    String cs = "abcdefghijklmnopqrstuvwxyz";
    static JLabel l1, l2, l3, l4, l5;
    JButton b1, b2, b3;
    JTextField t1, t2;
    JProgressBar progress;
    int num = 0;
    String en = "";

    ceasarclient(final Socket s) {
        super("CLIENT");
        JPanel p = new JPanel(new GridLayout(10, 1));
        setSize(500, 500);
        t1 = new JTextField(30);
        b1 = new JButton("Send");
        b1.setMnemonic('S');
        b2 = new JButton("Close");
        b2.setMnemonic('C');
        l1 = new JLabel("Welcome to Secure Data transfer!");
        l2 = new JLabel("Enter the word here...");
        l3 = new JLabel("");
        l4 = new JLabel("Enter the Key:");
        b3 = new JButton("Encrypt");
        b3.setMnemonic('E');
        t2 = new JTextField(30);
        progress = new JProgressBar(0, 20);
        progress.setValue(0);
        progress.setStringPainted(true);
        p.add(l1);
        p.add(l2);
        p.add(t1);
        p.add(l4);
        p.add(t2);
        p.add(b3);
        p.add(progress);
        p.add(b1);
        p.add(l3);
        p.add(b2);
        add(p);
        setVisible(true);
        b1.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                try {
                    PrintWriter pw = new PrintWriter(s.getOutputStream(), true);
                    pw.println(en);
                } catch (Exception ex) {
                }
                ;
                l3.setText("Encrypted Text Sent.");
            }
        });
        b3.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                String strw = t1.getText();
                int key = Integer.parseInt(t2.getText());
                int i = 0, j, k;
                while (i < strw.length()) {
                    j = cs.indexOf(strw.charAt(i));
                    k = (j + key) % 26;
                    en = en + cs.charAt(k);
                    i++;
                }
                while (num < 21) {
                    progress.setValue(num);
                    try {
                        Thread.sleep(100);
                    } catch (InterruptedException exe) {
                    }
                    progress.setValue(num);
                    Rectangle progressRect = progress.getBounds();
                    progressRect.x = 0;
                    progressRect.y = 0;
                    progress.paintImmediately(progressRect);
                    num++;
                }
            }
        });
        b2.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        pack();
    }

    public static void main(String args[]) throws IOException {
        final Socket s = new Socket(InetAddress.getLocalHost(), 4321);
        new ceasarclient(s);
    }
}

How to get an enum value from a string value in Java?

Fastest way to get the name of enum is to create a map of enum text and value when the application start, and to get the name call the function Blah.getEnumName():

public enum Blah {
    A("text1"),
    B("text2"),
    C("text3"),
    D("text4");

    private String text;
    private HashMap<String, String> map;
    Blah(String text) {
    this.text = text;
    }

    public String getText() {
      return this.text;
    }

    static{
      createMapOfTextAndName();
    }

    public static void createMapOfTextAndName() {
        map = new HashMap<String, String>();
        for (Blah b : Blah.values()) {
             map.put(b.getText(),b.name());
        }
    }
    public static String getEnumName(String text) {
        return map.get(text.toLowerCase());
    } 
}

Why avoid increment ("++") and decrement ("--") operators in JavaScript?

In my view, "Explicit is always better than implicit." Because at some point, you may got confused with this increments statement y+ = x++ + ++y. A good programmer always makes his or her code more readable.

Return Index of an Element in an Array Excel VBA

array of variants:

    Public Function GetIndex(ByRef iaList() As Variant, ByVal value As Variant) As Long

    Dim i As Long

     For i = LBound(iaList) To UBound(iaList)
      If value = iaList(i) Then
       GetIndex = i
       Exit For
      End If
     Next i

    End Function

a fastest version for integers (as pref tested below)

    Public Function GetIndex(ByRef iaList() As Integer, ByVal value As Integer) As Integer
     Dim i As Integer

     For i = LBound(iaList) To UBound(iaList)
      If iaList(i) = value Then: GetIndex = i: Exit For:
     Next i

    End Function

' a snippet, replace myList and myValue to your varible names: (also have not tested)

a snippet, lets test the assumption the passing by reference as argument means something. (the answer is no) to use it replace myList and myValue to your variable names:

  Dim found As Integer, foundi As Integer ' put only once
  found = -1
  For foundi = LBound(myList) To UBound(myList):
   If myList(foundi) = myValue Then
    found = foundi: Exit For
   End If
  Next
  result = found

to prove the point I have made some benchmarks

here are the results:

---------------------------
Milliseconds
---------------------------
result0: 5 ' just empty loop

result1: 2702  ' function variant array

result2: 1498  ' function integer array

result3: 2511 ' snippet variant array

result4: 1508 ' snippet integer array

result5: 58493 ' excel function Application.Match on variant array

result6: 136128 ' excel function Application.Match on integer array
---------------------------
OK   
---------------------------

a module:

Public Declare Function GetTickCount Lib "kernel32.dll" () As Long
#If VBA7 Then
    Public Declare PtrSafe Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As LongPtr) 'For 64 Bit Systems
#Else
    Public Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long) 'For 32 Bit Systems
#End If

    Public Function GetIndex1(ByRef iaList() As Variant, ByVal value As Variant) As Long

    Dim i As Long

     For i = LBound(iaList) To UBound(iaList)
      If value = iaList(i) Then
       GetIndex = i
       Exit For
      End If
     Next i

    End Function


'maybe a faster variant for integers

    Public Function GetIndex2(ByRef iaList() As Integer, ByVal value As Integer) As Integer
     Dim i As Integer

     For i = LBound(iaList) To UBound(iaList)
      If iaList(i) = value Then: GetIndex = i: Exit For:
     Next i

    End Function

' a snippet, replace myList and myValue to your varible names: (also have not tested)



    Public Sub test1()
     Dim i As Integer

     For i = LBound(iaList) To UBound(iaList)
      If iaList(i) = value Then: GetIndex = i: Exit For:
     Next i

    End Sub


Sub testTimer()

Dim myList(500) As Variant, myValue As Variant
Dim myList2(500) As Integer, myValue2 As Integer
Dim n

For n = 1 To 500
myList(n) = n
Next

For n = 1 To 500
myList2(n) = n
Next

myValue = 100
myValue2 = 100


Dim oPM
Set oPM = New PerformanceMonitor
Dim result0 As Long
Dim result1 As Long
Dim result2 As Long
Dim result3 As Long
Dim result4 As Long
Dim result5 As Long
Dim result6 As Long

Dim t As Long

Dim a As Long

a = 0
Dim i
't = GetTickCount
oPM.StartCounter
For i = 1 To 1000000

Next
result0 = oPM.TimeElapsed() '  GetTickCount - t

a = 0

't = GetTickCount
oPM.StartCounter
For i = 1 To 1000000
a = GetIndex1(myList, myValue)
Next
result1 = oPM.TimeElapsed()
'result1 = GetTickCount - t


a = 0

't = GetTickCount
oPM.StartCounter
For i = 1 To 1000000
a = GetIndex2(myList2, myValue2)
Next
result2 = oPM.TimeElapsed()
'result2 = GetTickCount - t



a = 0

't = GetTickCount

oPM.StartCounter
Dim found As Integer, foundi As Integer ' put only once
For i = 1 To 1000000
found = -1
For foundi = LBound(myList) To UBound(myList):
 If myList(foundi) = myValue Then
  found = foundi: Exit For
 End If
Next
a = found
Next
result3 = oPM.TimeElapsed()
'result3 = GetTickCount - t



a = 0

't = GetTickCount

oPM.StartCounter
For i = 1 To 1000000
found = -1
For foundi = LBound(myList2) To UBound(myList2):
 If myList2(foundi) = myValue2 Then
  found = foundi: Exit For
 End If
Next
a = found
Next
result4 = oPM.TimeElapsed()
'result4 = GetTickCount - t


a = 0

't = GetTickCount
oPM.StartCounter
For i = 1 To 1000000
a = pos = Application.Match(myValue, myList, False)
Next
result5 = oPM.TimeElapsed()
'result5 = GetTickCount - t



a = 0

't = GetTickCount
oPM.StartCounter
For i = 1 To 1000000
a = pos = Application.Match(myValue2, myList2, False)
Next
result6 = oPM.TimeElapsed()
'result6 = GetTickCount - t


MsgBox "result0: " & result0 & vbCrLf & "result1: " & result1 & vbCrLf & "result2: " & result2 & vbCrLf & "result3: " & result3 & vbCrLf & "result4: " & result4 & vbCrLf & "result5: " & result5 & vbCrLf & "result6: " & result6, , "Milliseconds"
End Sub

a class named PerformanceMonitor

Option Explicit

Private Type LARGE_INTEGER
    lowpart As Long
    highpart As Long
End Type

Private Declare Function QueryPerformanceCounter Lib "kernel32" (lpPerformanceCount As LARGE_INTEGER) As Long
Private Declare Function QueryPerformanceFrequency Lib "kernel32" (lpFrequency As LARGE_INTEGER) As Long

Private m_CounterStart As LARGE_INTEGER
Private m_CounterEnd As LARGE_INTEGER
Private m_crFrequency As Double

Private Const TWO_32 = 4294967296# ' = 256# * 256# * 256# * 256#

Private Function LI2Double(LI As LARGE_INTEGER) As Double
Dim Low As Double
    Low = LI.lowpart
    If Low < 0 Then
        Low = Low + TWO_32
    End If
    LI2Double = LI.highpart * TWO_32 + Low
End Function

Private Sub Class_Initialize()
Dim PerfFrequency As LARGE_INTEGER
    QueryPerformanceFrequency PerfFrequency
    m_crFrequency = LI2Double(PerfFrequency)
End Sub

Public Sub StartCounter()
    QueryPerformanceCounter m_CounterStart
End Sub

Property Get TimeElapsed() As Double
Dim crStart As Double
Dim crStop As Double
    QueryPerformanceCounter m_CounterEnd
    crStart = LI2Double(m_CounterStart)
    crStop = LI2Double(m_CounterEnd)
    TimeElapsed = 1000# * (crStop - crStart) / m_crFrequency
End Property

#if DEBUG vs. Conditional("DEBUG")

Well, it's worth noting that they don't mean the same thing at all.

If the DEBUG symbol isn't defined, then in the first case the SetPrivateValue itself won't be called... whereas in the second case it will exist, but any callers who are compiled without the DEBUG symbol will have those calls omitted.

If the code and all its callers are in the same assembly this difference is less important - but it means that in the first case you also need to have #if DEBUG around the calling code as well.

Personally I'd recommend the second approach - but you do need to keep the difference between them clear in your head.

Converting java.util.Properties to HashMap<String,String>

The efficient way to do that is just to cast to a generic Map as follows:

Properties props = new Properties();

Map<String, String> map = (Map)props;

This will convert a Map<Object, Object> to a raw Map, which is "ok" for the compiler (only warning). Once we have a raw Map it will cast to Map<String, String> which it also will be "ok" (another warning). You can ignore them with annotation @SuppressWarnings({ "unchecked", "rawtypes" })

This will work because in the JVM the object doesn't really have a generic type. Generic types are just a trick that verifies things at compile time.

If some key or value is not a String it will produce a ClassCastException error. With current Properties implementation this is very unlikely to happen, as long as you don't use the mutable call methods from the super Hashtable<Object,Object> of Properties.

So, if don't do nasty things with your Properties instance this is the way to go.

How do I increase the cell width of the Jupyter/ipython notebook in my browser?

I made some modification to @jvd10's solution. The '!important' seems too strong that the container doesn't adapt well when TOC sidebar is displayed. I removed it and added 'min-width' to limit the minimal width.

Here is my .juyputer/custom/custom.css:

/* Make the notebook cells take almost all available width and limit minimal width to 1110px */
.container {
    width: 99%;
    min-width: 1110px;
}   

/* Prevent the edit cell highlight box from getting clipped;
 * important so that it also works when cell is in edit mode*/
div.cell.selected {
    border-left-width: 1px;
}

How can I indent multiple lines in Xcode?

For those of you with Spanish keyboard on mac this are the shortcuts:

? + ? + [ for un-indent

? + ? + ] for indent

Difference between Relative path and absolute path in javascript

If you use the relative version on http://www.foo.com/abc your browser will look at http://www.foo.com/abc/kitten.png for the image and would get 404 - Not found.