Programs & Examples On #Boundary

GIT_DISCOVERY_ACROSS_FILESYSTEM not set

Check whether you are actually under a github repo.

So, listing of .git/ should give you results..otherwise you may be some level outside your repo.

Now, cd to your repo and you are good to go.

How to add a button dynamically in Android?

Button btn = new Button(this);
btn.setText("Submit");
LinearLayout linearLayout = (LinearLayout)findViewById(R.id.buttonlayout);
LayoutParams buttonlayout = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
linearLayout.addView(btn, buttonlayout);

AJAX in Chrome sending OPTIONS instead of GET/POST/PUT/DELETE?

In my case I'm calling an API hosted by AWS (API Gateway). The error happened when I tried to call the API from a domain other than the API own domain. Since I'm the API owner I enabled CORS for the test environment, as described in the Amazon Documentation.

In production this error will not happen, since the request and the api will be in the same domain.

I hope it helps!

Render basic HTML view?

If you want to render HTML file you can use sendFile() method without using any template engine

const express =  require("express")
const path = require("path")
const app = express()
app.get("/",(req,res)=>{
    res.sendFile(**path.join(__dirname, 'htmlfiles\\index.html')**)
})
app.listen(8000,()=>{
    console.log("server is running at Port 8000");
})

I have an HTML file inside htmlfile so I used path module to render index.html path is default module in node. if your file is present in root folder just used

res.sendFile(path.join(__dirname, 'htmlfiles\\index.html'))

inside app.get() it will work

What does operator "dot" (.) mean?

There is a whole page in the MATLAB documentation dedicated to this topic: Array vs. Matrix Operations. The gist of it is below:

MATLAB® has two different types of arithmetic operations: array operations and matrix operations. You can use these arithmetic operations to perform numeric computations, for example, adding two numbers, raising the elements of an array to a given power, or multiplying two matrices.

Matrix operations follow the rules of linear algebra. By contrast, array operations execute element by element operations and support multidimensional arrays. The period character (.) distinguishes the array operations from the matrix operations. However, since the matrix and array operations are the same for addition and subtraction, the character pairs .+ and .- are unnecessary.

MySQL Workbench Edit Table Data is read only

Yes, I found MySQL also cannot edit result tables. Usually results tables joining other tables don't have primary keys. I heard other suggested put the result table in another table, but the better solution is to use Dbeaver which can edit result tables.

Python non-greedy regexes

>>> x = "a (b) c (d) e"
>>> re.search(r"\(.*\)", x).group()
'(b) c (d)'
>>> re.search(r"\(.*?\)", x).group()
'(b)'

According to the docs:

The '*', '+', and '?' qualifiers are all greedy; they match as much text as possible. Sometimes this behavior isn’t desired; if the RE <.*> is matched against '<H1>title</H1>', it will match the entire string, and not just '<H1>'. Adding '?' after the qualifier makes it perform the match in non-greedy or minimal fashion; as few characters as possible will be matched. Using .*? in the previous expression will match only '<H1>'.

How can I clear console

The easiest way for me without having to reinvent the wheel.

void Clear()
{
#if defined _WIN32
    system("cls");
    //clrscr(); // including header file : conio.h
#elif defined (__LINUX__) || defined(__gnu_linux__) || defined(__linux__)
    system("clear");
    //std::cout<< u8"\033[2J\033[1;1H"; //Using ANSI Escape Sequences 
#elif defined (__APPLE__)
    system("clear");
#endif
}
  • On Windows you can use "conio.h" header and call clrscr function to avoid the use of system funtion.
#include <conio.h>
clrscr();
  • On Linux you can use ANSI Escape sequences to avoid use of system function. Check this reference ANSI Escape Sequences
    std::cout<< u8"\033[2J\033[1;1H"; 
  • On MacOS Investigating...

How to delete multiple pandas (python) dataframes from memory to save RAM?

del statement does not delete an instance, it merely deletes a name.

When you do del i, you are deleting just the name i - but the instance is still bound to some other name, so it won't be Garbage-Collected.

If you want to release memory, your dataframes has to be Garbage-Collected, i.e. delete all references to them.

If you created your dateframes dynamically to list, then removing that list will trigger Garbage Collection.

>>> lst = [pd.DataFrame(), pd.DataFrame(), pd.DataFrame()]
>>> del lst     # memory is released

If you created some variables, you have to delete them all.

>>> a, b, c = pd.DataFrame(), pd.DataFrame(), pd.DataFrame()
>>> lst = [a, b, c]
>>> del a, b, c # dfs still in list
>>> del lst     # memory release now

How to check whether a pandas DataFrame is empty?

To see if a dataframe is empty, I argue that one should test for the length of a dataframe's columns index:

if len(df.columns) == 0: 1

Reason:

According to the Pandas Reference API, there is a distinction between:

  • an empty dataframe with 0 rows and 0 columns
  • an empty dataframe with rows containing NaN hence at least 1 column

Arguably, they are not the same. The other answers are imprecise in that df.empty, len(df), or len(df.index) make no distinction and return index is 0 and empty is True in both cases.

Examples

Example 1: An empty dataframe with 0 rows and 0 columns

In [1]: import pandas as pd
        df1 = pd.DataFrame()
        df1
Out[1]: Empty DataFrame
        Columns: []
        Index: []

In [2]: len(df1.index)  # or len(df1)
Out[2]: 0

In [3]: df1.empty
Out[3]: True

Example 2: A dataframe which is emptied to 0 rows but still retains n columns

In [4]: df2 = pd.DataFrame({'AA' : [1, 2, 3], 'BB' : [11, 22, 33]})
        df2
Out[4]:    AA  BB
        0   1  11
        1   2  22
        2   3  33

In [5]: df2 = df2[df2['AA'] == 5]
        df2
Out[5]: Empty DataFrame
        Columns: [AA, BB]
        Index: []

In [6]: len(df2.index)  # or len(df2)
Out[6]: 0

In [7]: df2.empty
Out[7]: True

Now, building on the previous examples, in which the index is 0 and empty is True. When reading the length of the columns index for the first loaded dataframe df1, it returns 0 columns to prove that it is indeed empty.

In [8]: len(df1.columns)
Out[8]: 0

In [9]: len(df2.columns)
Out[9]: 2

Critically, while the second dataframe df2 contains no data, it is not completely empty because it returns the amount of empty columns that persist.

Why it matters

Let's add a new column to these dataframes to understand the implications:

# As expected, the empty column displays 1 series
In [10]: df1['CC'] = [111, 222, 333]
         df1
Out[10]:    CC
         0 111
         1 222
         2 333
In [11]: len(df1.columns)
Out[11]: 1

# Note the persisting series with rows containing `NaN` values in df2
In [12]: df2['CC'] = [111, 222, 333]
         df2
Out[12]:    AA  BB   CC
         0 NaN NaN  111
         1 NaN NaN  222
         2 NaN NaN  333
In [13]: len(df2.columns)
Out[13]: 3

It is evident that the original columns in df2 have re-surfaced. Therefore, it is prudent to instead read the length of the columns index with len(pandas.core.frame.DataFrame.columns) to see if a dataframe is empty.

Practical solution

# New dataframe df
In [1]: df = pd.DataFrame({'AA' : [1, 2, 3], 'BB' : [11, 22, 33]})
        df
Out[1]:    AA  BB
        0   1  11
        1   2  22
        2   3  33

# This data manipulation approach results in an empty df
# because of a subset of values that are not available (`NaN`)
In [2]: df = df[df['AA'] == 5]
        df
Out[2]: Empty DataFrame
        Columns: [AA, BB]
        Index: []

# NOTE: the df is empty, BUT the columns are persistent
In [3]: len(df.columns)
Out[3]: 2

# And accordingly, the other answers on this page
In [4]: len(df.index)  # or len(df)
Out[4]: 0

In [5]: df.empty
Out[5]: True
# SOLUTION: conditionally check for empty columns
In [6]: if len(df.columns) != 0:  # <--- here
            # Do something, e.g. 
            # drop any columns containing rows with `NaN`
            # to make the df really empty
            df = df.dropna(how='all', axis=1)
        df
Out[6]: Empty DataFrame
        Columns: []
        Index: []

# Testing shows it is indeed empty now
In [7]: len(df.columns)
Out[7]: 0

Adding a new data series works as expected without the re-surfacing of empty columns (factually, without any series that were containing rows with only NaN):

In [8]: df['CC'] = [111, 222, 333]
         df
Out[8]:    CC
         0 111
         1 222
         2 333
In [9]: len(df.columns)
Out[9]: 1

How to export datagridview to excel using vb.net?

another easy way and more flexible , after loading data into Datagrid

Private Sub Button_Export_Click(sender As Object, e As EventArgs) Handles Button_Export.Click
    Dim file As System.IO.StreamWriter
    file = My.Computer.FileSystem.OpenTextFileWriter("c:\1\Myfile.csv", True)
    If DataGridView1.Rows.Count = 0 Then GoTo loopend

    ' collect the header's names 
    Dim Headerline As String
    For k = 0 To DataGridView1.Columns.Count - 1
        If k = DataGridView1.Columns.Count - 1 Then ' last column dont put , separate 
            Headerline = Headerline & DataGridView1.Columns(k).HeaderText
        Else
            Headerline = Headerline & DataGridView1.Columns(k).HeaderText & ","
        End If
    Next
    file.WriteLine(Headerline)  ' this will write header names at the first line 
    ' collect the data 

    For i = 0 To DataGridView1.Rows.Count - 1
        Dim DataRow As String
        For k = 0 To DataGridView1.Columns.Count - 1
            If k = DataGridView1.Columns.Count - 1 Then
                DataRow = DataRow & DataGridView1.Rows(i).Cells(k).Value ' last column dont put , separate 
            End If
            DataRow = DataRow & DataGridView1.Rows(i).Cells(k).Value & ","
        Next

        file.WriteLine(DataRow)
        DataRow = ""
    Next



loopend:
        file.Close()
End Sub

Delete specific line number(s) from a text file using sed?

If you want to delete lines 5 through 10 and 12:

sed -e '5,10d;12d' file

This will print the results to the screen. If you want to save the results to the same file:

sed -i.bak -e '5,10d;12d' file

This will back the file up to file.bak, and delete the given lines.

Note: Line numbers start at 1. The first line of the file is 1, not 0.

How to watch and reload ts-node when TypeScript files change

I would prefer to not use ts-node and always run from dist folder.

To do that, just setup your package.json with default config:

....
"main": "dist/server.js",
  "scripts": {
    "build": "tsc",
    "prestart": "npm run build",
    "start": "node .",
    "dev": "nodemon"
  },
....

and then add nodemon.json config file:

{
  "watch": ["src"],
  "ext": "ts",
  "ignore": ["src/**/*.spec.ts"],
  "exec": "npm restart"
}

Here, i use "exec": "npm restart"
so all ts file will re-compile to js file and then restart the server.

To run while in dev environment,

npm run dev

Using this setup I will always run from the distributed files and no need for ts-node.

Find directory name with wildcard or similar to "like"

find supports wildcard matches, just add a *:

find / -type d -name "ora10*"

Best way to import Observable from rxjs

One thing I've learnt the hard way is being consistent

Watch out for mixing:

 import { BehaviorSubject } from "rxjs";

with

 import { BehaviorSubject } from "rxjs/BehaviorSubject";

This will probably work just fine UNTIL you try to pass the object to another class (where you did it the other way) and then this can fail

 (myBehaviorSubject instanceof Observable)

It fails because the prototype chain will be different and it will be false.

I can't pretend to understand exactly what is happening but sometimes I run into this and need to change to the longer format.

How to create a POJO?

When you aren't doing anything to make your class particularly designed to work with a given framework, ORM, or other system that needs a special sort of class, you have a Plain Old Java Object, or POJO.

Ironically, one of the reasons for coining the term is that people were avoiding them in cases where they were sensible and some people concluded that this was because they didn't have a fancy name. Ironic, because your question demonstrates that the approach worked.

Compare the older POD "Plain Old Data" to mean a C++ class that doesn't do anything a C struct couldn't do (more or less, non-virtual members that aren't destructors or trivial constructors don't stop it being considered POD), and the newer (and more directly comparable) POCO "Plain Old CLR Object" in .NET.

Java JTable setting Column Width

With JTable.AUTO_RESIZE_OFF, the table will not change the size of any of the columns for you, so it will take your preferred setting. If it is your goal to have the columns default to your preferred size, except to have the last column fill the rest of the pane, You have the option of using the JTable.AUTO_RESIZE_LAST_COLUMN autoResizeMode, but it might be most effective when used with TableColumn.setMaxWidth() instead of TableColumn.setPreferredWidth() for all but the last column.

Once you are satisfied that AUTO_RESIZE_LAST_COLUMN does in fact work, you can experiment with a combination of TableColumn.setMaxWidth() and TableColumn.setMinWidth()

How to install Python package from GitHub?

To install Python package from github, you need to clone that repository.

git clone https://github.com/jkbr/httpie.git

Then just run the setup.py file from that directory,

sudo python setup.py install

Set "Homepage" in Asp.Net MVC

Step 1: Click on Global.asax File in your Solution.

Step 2: Then Go to Definition of

RouteConfig.RegisterRoutes(RouteTable.Routes);

Step 3: Change Controller Name and View Name

public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

        routes.MapRoute(name: "Default",
                        url: "{controller}/{action}/{id}",
                        defaults: new { controller = "Home", 
                                        action = "Index", 
                                        id = UrlParameter.Optional }
                        );
    }
}

Trying to include a library, but keep getting 'undefined reference to' messages

Yes, It is required to add libraries after the source files/objects files. This command will solve the problem:

gcc -static -L/usr/lib -I/usr/lib main.c -ltommath

Hibernate Annotations - Which is better, field or property access?

Here's a situation where you HAVE to use property accessors. Imagine you have a GENERIC abstract class with lots of implementation goodness to inherit into 8 concrete subclasses:

public abstract class Foo<T extends Bar> {

    T oneThing;
    T anotherThing;

    // getters and setters ommited for brevity

    // Lots and lots of implementation regarding oneThing and anotherThing here
 }

Now exactly how should you annotate this class? The answer is YOU CAN'T annotate it at all with either field or property access because you can't specify the target entity at this point. You HAVE to annotate the concrete implementations. But since the persisted properties are declared in this superclass, you MUST used property access in the subclasses.

Field access is not an option in an application with abstract generic super-classes.

What is the boundary in multipart/form-data?

The exact answer to the question is: yes, you can use an arbitrary value for the boundary parameter, given it does not exceed 70 bytes in length and consists only of 7-bit US-ASCII (printable) characters.

If you are using one of multipart/* content types, you are actually required to specify the boundary parameter in the Content-Type header, otherwise the server (in the case of an HTTP request) will not be able to parse the payload.

You probably also want to set the charset parameter to UTF-8 in your Content-Type header, unless you can be absolutely sure that only US-ASCII charset will be used in the payload data.

A few relevant excerpts from the RFC2046:

  • 4.1.2. Charset Parameter:

    Unlike some other parameter values, the values of the charset parameter are NOT case sensitive. The default character set, which must be assumed in the absence of a charset parameter, is US-ASCII.

  • 5.1. Multipart Media Type

    As stated in the definition of the Content-Transfer-Encoding field [RFC 2045], no encoding other than "7bit", "8bit", or "binary" is permitted for entities of type "multipart". The "multipart" boundary delimiters and header fields are always represented as 7bit US-ASCII in any case (though the header fields may encode non-US-ASCII header text as per RFC 2047) and data within the body parts can be encoded on a part-by-part basis, with Content-Transfer-Encoding fields for each appropriate body part.

    The Content-Type field for multipart entities requires one parameter, "boundary". The boundary delimiter line is then defined as a line consisting entirely of two hyphen characters ("-", decimal value 45) followed by the boundary parameter value from the Content-Type header field, optional linear whitespace, and a terminating CRLF.

    Boundary delimiters must not appear within the encapsulated material, and must be no longer than 70 characters, not counting the two leading hyphens.

    The boundary delimiter line following the last body part is a distinguished delimiter that indicates that no further body parts will follow. Such a delimiter line is identical to the previous delimiter lines, with the addition of two more hyphens after the boundary parameter value.

Here is an example using an arbitrary boundary:

Content-Type: multipart/form-data; charset=utf-8; boundary="another cool boundary"

--another cool boundary
Content-Disposition: form-data; name="foo"

bar
--another cool boundary
Content-Disposition: form-data; name="baz"

quux
--another cool boundary--

How do I resolve "Please make sure that the file is accessible and that it is a valid assembly or COM component"?

Make sure the required dlls are exported (or copied manually) to the bin folder when building your application.

Android Studio update -Error:Could not run build action using Gradle distribution

I had the same problem and I Just Invalidate caches/restart

App.Config Transformation for projects which are not Web Projects in Visual Studio?

You can use a separate config file per configuration, e.g. app.Debug.config, app.Release.config and then use the configuration variable in your project file:

<PropertyGroup>
    <AppConfig>App.$(Configuration).config</AppConfig>
</PropertyGroup>

This will then create the correct ProjectName.exe.config file depending on the configuration you are building in.

Remove non-ascii character in string

You can use the following regex to replace non-ASCII characters

str = str.replace(/[^A-Za-z 0-9 \.,\?""!@#\$%\^&\*\(\)-_=\+;:<>\/\\\|\}\{\[\]`~]*/g, '')

However, note that spaces, colons and commas are all valid ASCII, so the result will be

> str
"INFO] :, , ,  (Higashikurume)"

Could not connect to SMTP host: localhost, port: 25; nested exception is: java.net.ConnectException: Connection refused: connect

First you have to ensure that there is a SMTP server listening on port 25.

To look whether you have the service, you can try using TELNET client, such as:

C:\> telnet localhost 25

(telnet client by default is disabled on most recent versions of Windows, you have to add/enable the Windows component from Control Panel. In Linux/UNIX usually telnet client is there by default.

$ telnet localhost 25

If it waits for long then time out, that means you don't have the required SMTP service. If successfully connected you enter something and able to type something, the service is there.

If you don't have the service, you can use these:

  • A mock SMTP server that will mimic the behavior of actual SMTP server, as you are using Java, it is natural to suggest Dumbster fake SMTP server. This even can be made to work within JUnit tests (with setup/tear down/validation), or independently run as separate process for integration test.
  • If your host is Windows, you can try installing Mercury email server (also comes with WAMPP package from Apache Friends) on your local before running above code.
  • If your host is Linux or UNIX, try to enable the mail service such as Postfix,
  • Another full blown SMTP server in Java, such as Apache James mail server.

If you are sure that you already have the service, may be the SMTP requires additional security credentials. If you can tell me what SMTP server listening on port 25 I may be able to tell you more.

error, string or binary data would be truncated when trying to insert

Kevin Pope's comment under the accepted answer was what I needed.

The problem, in my case, was that I had triggers defined on my table that would insert update/insert transactions into an audit table, but the audit table had a data type mismatch where a column with VARCHAR(MAX) in the original table was stored as VARCHAR(1) in the audit table, so my triggers were failing when I would insert anything greater than VARCHAR(1) in the original table column and I would get this error message.

Convert integer into byte array (Java)

This will help you.

import java.nio.ByteBuffer;
import java.util.Arrays;

public class MyClass
{
    public static void main(String args[]) {
        byte [] hbhbytes = ByteBuffer.allocate(4).putInt(16666666).array();

        System.out.println(Arrays.toString(hbhbytes));
    }
}

SOAP or REST for Web Services?

SOAP currently has the advantage of better tools where they will generate a lot of the boilerplate code for both the service layer as well as generating clients from any given WSDL.

REST is simpler, can be easier to maintain as a result, lies at the heart of Web architecture, allows for better protocol visibility, and has been proven to scale at the size of the WWW itself. Some frameworks out there help you build REST services, like Ruby on Rails, and some even help you with writing clients, like ADO.NET Data Services. But for the most part, tool support is lacking.

Matplotlib/pyplot: How to enforce axis range?

To answer my own question, the trick is to turn auto scaling off...

p.axis([0.0,600.0, 10000.0,20000.0])
ax = p.gca()
ax.set_autoscale_on(False)

How to get N rows starting from row M from sorted table in T-SQL

In order to do this in SQL Server, you must order the query by a column, so you can specify the rows you want.

You can't use the "TOP" keyword when doing this, you must use offset N rows fetch next M rows.

Example:

select * from table order by [some_column] 
offset 10 rows
FETCH NEXT 10 rows only

You can learn more here: https://technet.microsoft.com/pt-br/library/gg699618%28v=sql.110%29.aspx

Programmatically retrieve SQL Server stored procedure source that is identical to the source returned by the SQL Server Management Studio gui?

You said programmatically, right? I hope C# is ok. I know you said that you tried SMO and it didn't quite do what you wanted, so this probably won't be perfect for your request, but it will programmatically read out legit SQL statements that you could run to recreate the stored procedure. If it doesn't have the GO statements that you want, you can probably assume that each of the strings in the StringCollection could have a GO after it. You may not get that comment with the date and time in it, but in my similar sounding project (big-ass deployment tool that has to back up everything individually), this has done rather nicely. If you have a prior base that you wanted to work from, and you still have the original database to run this on, I'd consider tossing the initial effort and restandardizing on this output.

using System.Data.SqlClient;
using Microsoft.SqlServer.Management.Common;
using Microsoft.SqlServer.Management.Smo;
…
string connectionString = … /* some connection string */;
ServerConnection sc = new ServerConnection(connectionString);
Server s = new Server(connection);
Database db = new Database(s, … /* database name */);
StoredProcedure sp = new StoredProcedure(db, … /* stored procedure name */);
StringCollection statements = sp.Script;

$http.get(...).success is not a function

If you are trying to use AngularJs 1.6.6 as of 21/10/2017 the following parameter works as .success and has been depleted. The .then() method takes two arguments: a response and an error callback which will be called with a response object.

 $scope.login = function () {
        $scope.btntext = "Please wait...!";
        $http({
            method: "POST",
            url: '/Home/userlogin', // link UserLogin with HomeController 
            data: $scope.user
         }).then(function (response) {
            console.log("Result value is : " + parseInt(response));
            data = response.data;
            $scope.btntext = 'Login';
            if (data == 1) {
                window.location.href = '/Home/dashboard';
             }
            else {
            alert(data);
        }
        }, function (error) {

        alert("Failed Login");
        });

The above snipit works for a login page.

Python: Converting string into decimal number

If you are converting string to float:

import re
A1 = [' "29.0" ',' "65.2" ',' "75.2" ']
float_values = [float(re.search(r'\d+.\d+',number).group()) for number in A1]
print(float_values)
>>> [29.0, 65.2, 75.2]

httpd Server not started: (13)Permission denied: make_sock: could not bind to address [::]:88

At terminal run this command with root permission:

sudo /etc/init.d/apache2 start

You must be root for starting a webserver otherwise you would get similar error.

jQuery prevent change for select

This worked for me, no need to keep a lastSelected if you know the optionIndex to select.

var optionIndex = ...
$(this)[0].options[optionIndex].selected = true;

CURL to access a page that requires a login from a different page

The web site likely uses cookies to store your session information. When you run

curl --user user:pass https://xyz.com/a  #works ok
curl https://xyz.com/b #doesn't work

curl is run twice, in two separate sessions. Thus when the second command runs, the cookies set by the 1st command are not available; it's just as if you logged in to page a in one browser session, and tried to access page b in a different one.

What you need to do is save the cookies created by the first command:

curl --user user:pass --cookie-jar ./somefile https://xyz.com/a

and then read them back in when running the second:

curl --cookie ./somefile https://xyz.com/b

Alternatively you can try downloading both files in the same command, which I think will use the same cookies.

What is going wrong when Visual Studio tells me "xcopy exited with code 4"

Another thing to watch out for is double backslashes, since xcopy does not tolerate them in the input path parameter (but it does tolerate them in the output path...).

enter image description here

Convert the first element of an array to a string in PHP

Is there any other way to convert that array into string ?

You don't want to convert the array to a string, you want to get the value of the array's sole element, if I read it correctly.

<?php
  $foo = array( 18 => 'Something' );
  $value = array_shift( $foo );
  echo $value; // 'Something'.

?>

Using array_shift you don't have to worry about the index.

EDIT: Mind you, array_shift is not the only function that will return a single value. array_pop( ), current( ), end( ), reset( ), they will all return that one single element. All of the posted solutions work. Using array shift though, you can be sure that you'll only ever get the first value of the array, even when there are multiple.

WordPress is giving me 404 page not found for all pages except the homepage

For nginx users

Use the following in your conf file for your site (usually /etc/nginx/sites-available/example.com)

location / { try_files $uri $uri/ /index.php?q=$uri&$args; }

This hands off all permalink requests to index.php with a URI string and supplied arguments. Do a systemctl reload nginx to see the changes and your non-homepage links should load.

"Object doesn't support this property or method" error in IE11

I face the similar issue and surprisingly meta tag didn't work this time. Turns out the company I currently cooperate with has this enterprise mode setting which has priority over meta tag.

We can't change the setting cause policy issue. Luckily I don't really need any fancy features but basic usage of jQuery so my final solution is to switch its version to 1.12 for better compatibility.

ref: jQuery - Browser support

Imported a csv-dataset to R but the values becomes factors

for me the solution was to include skip = 0 (number of rows to skip at the top of the file. Can be set >0)

mydata <- read.csv(file = "file.csv", header = TRUE, sep = ",", skip = 22)

SQL SERVER DATETIME FORMAT

In MS SQL Server you can do:

SET DATEFORMAT ymd

Android Studio - Failed to notify project evaluation listener error

I had this issue because I was using Charles proxy on my computer and the SSL was enabled for all hosts. And since AS didn't trust my proxy, the network request failed. So I had to disable SSL for all hosts and restart my Android Studio.

How to read a single character from the user?

The (currently) top-ranked answer (with the ActiveState code) is overly complicated. I don't see a reason to use classes when a mere function should suffice. Below are two implementations that accomplish the same thing but with more readable code.

Both of these implementations:

  1. work just fine in Python 2 or Python 3
  2. work on Windows, OSX, and Linux
  3. read just one byte (i.e., they don't wait for a newline)
  4. don't depend on any external libraries
  5. are self-contained (no code outside of the function definition)

Version 1: readable and simple

def getChar():
    try:
        # for Windows-based systems
        import msvcrt # If successful, we are on Windows
        return msvcrt.getch()

    except ImportError:
        # for POSIX-based systems (with termios & tty support)
        import tty, sys, termios  # raises ImportError if unsupported

        fd = sys.stdin.fileno()
        oldSettings = termios.tcgetattr(fd)

        try:
            tty.setcbreak(fd)
            answer = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, oldSettings)

        return answer

Version 2: avoid repeated imports and exception handling:

[EDIT] I missed one advantage of the ActiveState code. If you plan to read characters multiple times, that code avoids the (negligible) cost of repeating the Windows import and the ImportError exception handling on Unix-like systems. While you probably should be more concerned about code readability than that negligible optimization, here is an alternative (it is similar to Louis's answer, but getChar() is self-contained) that functions the same as the ActiveState code and is more readable:

def getChar():
    # figure out which function to use once, and store it in _func
    if "_func" not in getChar.__dict__:
        try:
            # for Windows-based systems
            import msvcrt # If successful, we are on Windows
            getChar._func=msvcrt.getch

        except ImportError:
            # for POSIX-based systems (with termios & tty support)
            import tty, sys, termios # raises ImportError if unsupported

            def _ttyRead():
                fd = sys.stdin.fileno()
                oldSettings = termios.tcgetattr(fd)

                try:
                    tty.setcbreak(fd)
                    answer = sys.stdin.read(1)
                finally:
                    termios.tcsetattr(fd, termios.TCSADRAIN, oldSettings)

                return answer

            getChar._func=_ttyRead

    return getChar._func()

Example code that exercises either of the getChar() versions above:

from __future__ import print_function # put at top of file if using Python 2

# Example of a prompt for one character of input
promptStr   = "Please give me a character:"
responseStr = "Thank you for giving me a '{}'."
print(promptStr, end="\n> ")
answer = getChar()
print("\n")
print(responseStr.format(answer))

How to find rows that have a value that contains a lowercase letter

for search all rows in lowercase

SELECT *
FROM Test
WHERE col1 
LIKE '%[abcdefghijklmnopqrstuvwxyz]%'
collate Latin1_General_CS_AS

Thanks Manesh Joseph

Tools to selectively Copy HTML+CSS+JS From A Specific Element of DOM

I also need this feature on Firebug! Until then, another approach is to use this online service to remove classes and convert the css to inline styles.

How to center horizontally div inside parent div

<div id='parent' style='width: 100%;text-align:center;'>
 <div id='child' style='width:50px; height:100px;margin:0px auto;'>Text</div>
</div>

mysqld_safe Directory '/var/run/mysqld' for UNIX socket file don't exists

You may try the following if your database does not have any data OR you have another away to restore that data. You will need to know the Ubuntu server root password but not the mysql root password.

It is highly probably that many of us have installed "mysql_secure_installation" as this is a best practice. Navigate to bin directory where mysql_secure_installation exist. It can be found in the /bin directory on Ubuntu systems. By rerunning the installer, you will be prompted about whether to change root database password.

Regex for string not ending with given suffix

Try this

/.*[^a]$/

The [] denotes a character class, and the ^ inverts the character class to match everything but an a.

How can I make my layout scroll both horizontally and vertically?

Use this:

android:scrollbarAlwaysDrawHorizontalTrack="true"

Example:

<Gallery android:id="@+id/gallery"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:scrollbarAlwaysDrawHorizontalTrack="true" />

How to set environment variable or system property in spring tests?

You can set the System properties as VM arguments.

If your project is a maven project then you can execute following command while running the test class:

mvn test -Dapp.url="https://stackoverflow.com"

Test class:

public class AppTest  {
@Test
public void testUrl() {
    System.out.println(System.getProperty("app.url"));
    }
}

If you want to run individual test class or method in eclipse then :

1) Go to Run -> Run Configuration

2) On left side select your Test class under the Junit section.

3) do the following :

enter image description here

Rename specific column(s) in pandas

A much faster implementation would be to use list-comprehension if you need to rename a single column.

df.columns = ['log(gdp)' if x=='gdp' else x for x in df.columns]

If the need arises to rename multiple columns, either use conditional expressions like:

df.columns = ['log(gdp)' if x=='gdp' else 'cap_mod' if x=='cap' else x for x in df.columns]

Or, construct a mapping using a dictionary and perform the list-comprehension with it's get operation by setting default value as the old name:

col_dict = {'gdp': 'log(gdp)', 'cap': 'cap_mod'}   ## key?old name, value?new name

df.columns = [col_dict.get(x, x) for x in df.columns]

Timings:

%%timeit
df.rename(columns={'gdp':'log(gdp)'}, inplace=True)
10000 loops, best of 3: 168 µs per loop

%%timeit
df.columns = ['log(gdp)' if x=='gdp' else x for x in df.columns]
10000 loops, best of 3: 58.5 µs per loop

Create a symbolic link of directory in Ubuntu

That's what ln is documented to do when the target already exists and is a directory. If you want /etc/nginx to be a symlink rather than contain a symlink, you had better not create it as a directory first!

when I try to open an HTML file through `http://localhost/xampp/htdocs/index.html` it says unable to connect to localhost

You need to start your Apache Server normally you should have an xampp icon in the info-section from the taskbar, with this tool you can start the apache server as wel as the mysql database (if you need it)

<input type="file"> limit selectable files by extensions

Honestly, the best way to limit files is on the server side. People can spoof file type on the client so taking in the full file name at server transfer time, parsing out the file type, and then returning a message is usually the best bet.

How can I hide an HTML table row <tr> so that it takes up no space?

I would really like to see your TABLE's styling. E.g. "border-collapse"

Just a guess, but it might affect how 'hidden' rows are being rendered.

Create mysql table directly from CSV file using the CSV Storage engine?

you can use this bash script

convert.sh

and run

./convert.sh -f example/mycsvfile.csv

After Spring Boot 2.0 migration: jdbcUrl is required with driverClassName

In case you do need to define dataSource(), for example when you have multiple data sources, you can use:

@Autowired Environment env;

@Primary
@Bean
public DataSource customDataSource() {

    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName(env.getProperty("custom.datasource.driver-class-name"));
    dataSource.setUrl(env.getProperty("custom.datasource.url"));
    dataSource.setUsername(env.getProperty("custom.datasource.username"));
    dataSource.setPassword(env.getProperty("custom.datasource.password"));

    return dataSource;

}

By setting up the dataSource yourself (instead of using DataSourceBuilder), it fixed my problem which you also had.

The always knowledgeable Baeldung has a tutorial which explains in depth.

Where can I find a list of Mac virtual key codes?

Below is a list of the common key codes for quick reference, taken from Events.h.

If you need to use these keycodes in an application, you should include the Carbon framework:

Objective-C:
#include <Carbon/Carbon.h>

Swift:
import Carbon.HIToolbox

You can then use the kVK_ANSI_A constants directly.


WARNING

The key constants reference physical keys on the keyboard. Their output changes if the typist is using a different keyboard layout. The letters in the constants correspond only to the U.S. QWERTY keyboard layout.

For example, the left ring-finger key on the homerow:

QWERTY keyboard layout > s > kVK_ANSI_S > "s"
Dvorak keyboard layout > o > kVK_ANSI_S > "o"

Strategies for layout-agnostic conversion of keycode to string, and vice versa, are discussed here:

How to convert ASCII character to CGKeyCode?


From Events.h:

/*
 *  Summary:
 *    Virtual keycodes
 *  
 *  Discussion:
 *    These constants are the virtual keycodes defined originally in
 *    Inside Mac Volume V, pg. V-191. They identify physical keys on a
 *    keyboard. Those constants with "ANSI" in the name are labeled
 *    according to the key position on an ANSI-standard US keyboard.
 *    For example, kVK_ANSI_A indicates the virtual keycode for the key
 *    with the letter 'A' in the US keyboard layout. Other keyboard
 *    layouts may have the 'A' key label on a different physical key;
 *    in this case, pressing 'A' will generate a different virtual
 *    keycode.
 */
enum {
  kVK_ANSI_A                    = 0x00,
  kVK_ANSI_S                    = 0x01,
  kVK_ANSI_D                    = 0x02,
  kVK_ANSI_F                    = 0x03,
  kVK_ANSI_H                    = 0x04,
  kVK_ANSI_G                    = 0x05,
  kVK_ANSI_Z                    = 0x06,
  kVK_ANSI_X                    = 0x07,
  kVK_ANSI_C                    = 0x08,
  kVK_ANSI_V                    = 0x09,
  kVK_ANSI_B                    = 0x0B,
  kVK_ANSI_Q                    = 0x0C,
  kVK_ANSI_W                    = 0x0D,
  kVK_ANSI_E                    = 0x0E,
  kVK_ANSI_R                    = 0x0F,
  kVK_ANSI_Y                    = 0x10,
  kVK_ANSI_T                    = 0x11,
  kVK_ANSI_1                    = 0x12,
  kVK_ANSI_2                    = 0x13,
  kVK_ANSI_3                    = 0x14,
  kVK_ANSI_4                    = 0x15,
  kVK_ANSI_6                    = 0x16,
  kVK_ANSI_5                    = 0x17,
  kVK_ANSI_Equal                = 0x18,
  kVK_ANSI_9                    = 0x19,
  kVK_ANSI_7                    = 0x1A,
  kVK_ANSI_Minus                = 0x1B,
  kVK_ANSI_8                    = 0x1C,
  kVK_ANSI_0                    = 0x1D,
  kVK_ANSI_RightBracket         = 0x1E,
  kVK_ANSI_O                    = 0x1F,
  kVK_ANSI_U                    = 0x20,
  kVK_ANSI_LeftBracket          = 0x21,
  kVK_ANSI_I                    = 0x22,
  kVK_ANSI_P                    = 0x23,
  kVK_ANSI_L                    = 0x25,
  kVK_ANSI_J                    = 0x26,
  kVK_ANSI_Quote                = 0x27,
  kVK_ANSI_K                    = 0x28,
  kVK_ANSI_Semicolon            = 0x29,
  kVK_ANSI_Backslash            = 0x2A,
  kVK_ANSI_Comma                = 0x2B,
  kVK_ANSI_Slash                = 0x2C,
  kVK_ANSI_N                    = 0x2D,
  kVK_ANSI_M                    = 0x2E,
  kVK_ANSI_Period               = 0x2F,
  kVK_ANSI_Grave                = 0x32,
  kVK_ANSI_KeypadDecimal        = 0x41,
  kVK_ANSI_KeypadMultiply       = 0x43,
  kVK_ANSI_KeypadPlus           = 0x45,
  kVK_ANSI_KeypadClear          = 0x47,
  kVK_ANSI_KeypadDivide         = 0x4B,
  kVK_ANSI_KeypadEnter          = 0x4C,
  kVK_ANSI_KeypadMinus          = 0x4E,
  kVK_ANSI_KeypadEquals         = 0x51,
  kVK_ANSI_Keypad0              = 0x52,
  kVK_ANSI_Keypad1              = 0x53,
  kVK_ANSI_Keypad2              = 0x54,
  kVK_ANSI_Keypad3              = 0x55,
  kVK_ANSI_Keypad4              = 0x56,
  kVK_ANSI_Keypad5              = 0x57,
  kVK_ANSI_Keypad6              = 0x58,
  kVK_ANSI_Keypad7              = 0x59,
  kVK_ANSI_Keypad8              = 0x5B,
  kVK_ANSI_Keypad9              = 0x5C
};

/* keycodes for keys that are independent of keyboard layout*/
enum {
  kVK_Return                    = 0x24,
  kVK_Tab                       = 0x30,
  kVK_Space                     = 0x31,
  kVK_Delete                    = 0x33,
  kVK_Escape                    = 0x35,
  kVK_Command                   = 0x37,
  kVK_Shift                     = 0x38,
  kVK_CapsLock                  = 0x39,
  kVK_Option                    = 0x3A,
  kVK_Control                   = 0x3B,
  kVK_RightShift                = 0x3C,
  kVK_RightOption               = 0x3D,
  kVK_RightControl              = 0x3E,
  kVK_Function                  = 0x3F,
  kVK_F17                       = 0x40,
  kVK_VolumeUp                  = 0x48,
  kVK_VolumeDown                = 0x49,
  kVK_Mute                      = 0x4A,
  kVK_F18                       = 0x4F,
  kVK_F19                       = 0x50,
  kVK_F20                       = 0x5A,
  kVK_F5                        = 0x60,
  kVK_F6                        = 0x61,
  kVK_F7                        = 0x62,
  kVK_F3                        = 0x63,
  kVK_F8                        = 0x64,
  kVK_F9                        = 0x65,
  kVK_F11                       = 0x67,
  kVK_F13                       = 0x69,
  kVK_F16                       = 0x6A,
  kVK_F14                       = 0x6B,
  kVK_F10                       = 0x6D,
  kVK_F12                       = 0x6F,
  kVK_F15                       = 0x71,
  kVK_Help                      = 0x72,
  kVK_Home                      = 0x73,
  kVK_PageUp                    = 0x74,
  kVK_ForwardDelete             = 0x75,
  kVK_F4                        = 0x76,
  kVK_End                       = 0x77,
  kVK_F2                        = 0x78,
  kVK_PageDown                  = 0x79,
  kVK_F1                        = 0x7A,
  kVK_LeftArrow                 = 0x7B,
  kVK_RightArrow                = 0x7C,
  kVK_DownArrow                 = 0x7D,
  kVK_UpArrow                   = 0x7E
};

Macintosh Toolbox Essentials illustrates the physical locations of these virtual key codes for the Apple Extended Keyboard II in Figure 2-10:

Virtual key codes for the Apple Extended Keyboard II

MacOS Xcode CoreSimulator folder very big. Is it ok to delete content?

for Xcode 8:

What I do is run sudo du -khd 1 in the Terminal to see my file system's storage amounts for each folder in simple text, then drill up/down into where the huge GB are hiding using the cd command.

Ultimately you'll find the Users//Library/Developer/CoreSimulator/Devices folder where you can have little concern about deleting all those "devices" using iOS versions you no longer need. It's also safe to just delete them all, but keep in mind you'll lose data that's written to the device like sqlite files you may want to use as a backup version.

I once saved over 50GB doing this since I did so much testing on older iOS versions.

jquery animate .css

You can actually still use ".css" and apply css transitions to the div being affected. So continue using ".css" and add the below styles to your stylesheet for "#hfont1". Since ".css" allows for a lot more properties than ".animate", this is always my preferred method.

#hfont1 {
    -webkit-transition: width 0.4s;
    transition: width 0.4s;
}

Change/Get check state of CheckBox

Needs to be:

if (document.forms[0].elements["checkAddress"].checked == true)

Assuming you have one form, otherwise use the form name.

As a side note, don't call the element and the function in the same name it can cause weird conflicts.

Laravel form html with PUT method for PUT routes

Just use like this somewhere inside the form

@method('PUT')

How to create Select List for Country and States/province in MVC

I too liked Jordan's answer and implemented it myself. I only needed to abbreviations so in case someone else needs the same:

    public static IEnumerable<SelectListItem> GetStatesList()
    {
        IList<SelectListItem> states = new List<SelectListItem>
        {
            new SelectListItem() {Text="AL", Value="AL"},
            new SelectListItem() { Text="AK", Value="AK"},
            new SelectListItem() { Text="AZ", Value="AZ"},
            new SelectListItem() { Text="AR", Value="AR"},
            new SelectListItem() { Text="CA", Value="CA"},
            new SelectListItem() { Text="CO", Value="CO"},
            new SelectListItem() { Text="CT", Value="CT"},
            new SelectListItem() { Text="DC", Value="DC"},
            new SelectListItem() { Text="DE", Value="DE"},
            new SelectListItem() { Text="FL", Value="FL"},
            new SelectListItem() { Text="GA", Value="GA"},
            new SelectListItem() { Text="HI", Value="HI"},
            new SelectListItem() { Text="ID", Value="ID"},
            new SelectListItem() { Text="IL", Value="IL"},
            new SelectListItem() { Text="IN", Value="IN"},
            new SelectListItem() { Text="IA", Value="IA"},
            new SelectListItem() { Text="KS", Value="KS"},
            new SelectListItem() { Text="KY", Value="KY"},
            new SelectListItem() { Text="LA", Value="LA"},
            new SelectListItem() { Text="ME", Value="ME"},
            new SelectListItem() { Text="MD", Value="MD"},
            new SelectListItem() { Text="MA", Value="MA"},
            new SelectListItem() { Text="MI", Value="MI"},
            new SelectListItem() { Text="MN", Value="MN"},
            new SelectListItem() { Text="MS", Value="MS"},
            new SelectListItem() { Text="MO", Value="MO"},
            new SelectListItem() { Text="MT", Value="MT"},
            new SelectListItem() { Text="NE", Value="NE"},
            new SelectListItem() { Text="NV", Value="NV"},
            new SelectListItem() { Text="NH", Value="NH"},
            new SelectListItem() { Text="NJ", Value="NJ"},
            new SelectListItem() { Text="NM", Value="NM"},
            new SelectListItem() { Text="NY", Value="NY"},
            new SelectListItem() { Text="NC", Value="NC"},
            new SelectListItem() { Text="ND", Value="ND"},
            new SelectListItem() { Text="OH", Value="OH"},
            new SelectListItem() { Text="OK", Value="OK"},
            new SelectListItem() { Text="OR", Value="OR"},
            new SelectListItem() { Text="PA", Value="PA"},
            new SelectListItem() { Text="PR", Value="PR"},
            new SelectListItem() { Text="RI", Value="RI"},
            new SelectListItem() { Text="SC", Value="SC"},
            new SelectListItem() { Text="SD", Value="SD"},
            new SelectListItem() { Text="TN", Value="TN"},
            new SelectListItem() { Text="TX", Value="TX"},
            new SelectListItem() { Text="UT", Value="UT"},
            new SelectListItem() { Text="VT", Value="VT"},
            new SelectListItem() { Text="VA", Value="VA"},
            new SelectListItem() { Text="WA", Value="WA"},
            new SelectListItem() { Text="WV", Value="WV"},
            new SelectListItem() { Text="WI", Value="WI"},
            new SelectListItem() { Text="WY", Value="WY"}
        };
        return states;
    }

To add server using sp_addlinkedserver

I had the same issue to connect an SQL_server 2008 to an SQL_server 2016 hosted in a remote server. @Domnic answer didn't worked for me straightforward. I write my tweaked solution here as I think it may be useful for someone else.

An extended answer for remote IP db connections:

Step 1: Link servers

EXEC sp_addlinkedserver @server='SRV_NAME',
   @srvproduct=N'',
   @provider=N'SQLNCLI',   
   @datasrc=N'aaa.bbb.ccc.ddd';

EXEC sp_addlinkedsrvlogin 'SRV_NAME', 'false', NULL, 'your_remote_db_login_user', 'your_remote_db_login_password'

...where SRV_NAME is an invented name. We will use it to refer to the remote server from our queries. aaa.bbb.ccc.ddd is the ip address of the remote server hosting your SQLserver DB.

Step 2: Run your queries For instance:

SELECT * FROM [SRV_NAME].your_remote_db_name.dbo.your_table

...and that's it!

Syntax details: sp_addlinkedserver and sp_addlinkedsrvlogin

ActiveXObject creation error " Automation server can't create object"

This error is cause by security clutches between the web application and your java. To resolve it, look into your java setting under control panel. Move the security level to a medium.

How to Use Order By for Multiple Columns in Laravel 4?

You can do as @rmobis has specified in his answer, [Adding something more into it]

Using order by twice:

MyTable::orderBy('coloumn1', 'DESC')
    ->orderBy('coloumn2', 'ASC')
    ->get();

and the second way to do it is,

Using raw order by:

MyTable::orderByRaw("coloumn1 DESC, coloumn2 ASC");
    ->get();

Both will produce same query as follow,

SELECT * FROM `my_tables` ORDER BY `coloumn1` DESC, `coloumn2` ASC

As @rmobis specified in comment of first answer you can pass like an array to order by column like this,

$myTable->orders = array(
    array('column' => 'coloumn1', 'direction' => 'desc'), 
    array('column' => 'coloumn2', 'direction' => 'asc')
);

one more way to do it is iterate in loop,

$query = DB::table('my_tables');

foreach ($request->get('order_by_columns') as $column => $direction) {
    $query->orderBy($column, $direction);
}

$results = $query->get();

Hope it helps :)

Why do people hate SQL cursors so much?

You could have probably concluded your question after the second paragraph, rather than calling people "insane" simply because they have a different viewpoint than you do and otherwise trying to mock professionals who may have a very good reason for feeling the way that they do.

As to your question, while there are certainly situations where a cursor may be called for, in my experience developers decide that a cursor "must" be used FAR more often than is actually the case. The chance of someone erring on the side of too much use of cursors vs. not using them when they should is MUCH higher in my opinion.

DataGridView.Clear()

Try this Method

dataGridView1.DataSource = dt;
dt.Rows.Clear();

Numpy: Divide each row by a vector element

Adding to the answer of stackoverflowuser2010, in the general case you can just use

data = np.array([[1,1,1],[2,2,2],[3,3,3]])

vector = np.array([1,2,3])

data / vector.reshape(-1,1)

This will turn your vector into a column matrix/vector. Allowing you to do the elementwise operations as you wish. At least to me, this is the most intuitive way going about it and since (in most cases) numpy will just use a view of the same internal memory for the reshaping it's efficient too.

python multithreading wait till all threads finished

Put the threads in a list and then use the Join method

 threads = []

 t = Thread(...)
 threads.append(t)

 ...repeat as often as necessary...

 # Start all threads
 for x in threads:
     x.start()

 # Wait for all of them to finish
 for x in threads:
     x.join()

Msg 102, Level 15, State 1, Line 1 Incorrect syntax near ' '

For the OP's command:

select compid,2, convert(datetime, '01/01/' + CONVERT(char(4),cal_yr) ,101) ,0,  Update_dt, th1, th2, th3_pc , Update_id, Update_dt,1
from  #tmp_CTF** 

I get this error:

Msg 102, Level 15, State 1, Line 2
Incorrect syntax near '*'.

when debugging something like this split the long line up so you'll get a better row number:

select compid
,2
, convert(datetime
, '01/01/' 
+ CONVERT(char(4)
,cal_yr) 
,101) 
,0
,  Update_dt
, th1
, th2
, th3_pc 
, Update_id
, Update_dt
,1
from  #tmp_CTF** 

this now results in:

Msg 102, Level 15, State 1, Line 16
Incorrect syntax near '*'.

which is probably just from the OP not putting the entire command in the question, or use [ ] braces to signify the table name:

from [#tmp_CTF**]

if that is the table name.

Change Image of ImageView programmatically in Android

Use in XML:

android:src="@drawable/image"

Source use:

imageView.setImageDrawable(ContextCompat.getDrawable(activity, R.drawable.your_image));

Understanding Python super() with __init__() methods

super() lets you avoid referring to the base class explicitly, which can be nice. But the main advantage comes with multiple inheritance, where all sorts of fun stuff can happen. See the standard docs on super if you haven't already.

Note that the syntax changed in Python 3.0: you can just say super().__init__() instead of super(ChildB, self).__init__() which IMO is quite a bit nicer. The standard docs also refer to a guide to using super() which is quite explanatory.

C# - How to add an Excel Worksheet programmatically - Office XP / 2003

Would like to thank you for some excellent replies. @AR., your a star and it works perfectly. I had noticed last night that the Excel.exe was not closing; so I did some research and found out about how to release the COM objects. Here is my final code:

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using System.IO;
using Excel;

namespace testExcelconsoleApp
{
    class Program
    {
        private String fileLoc = @"C:\temp\test.xls";

        static void Main(string[] args)
        {
            Program p = new Program();
            p.createExcel();
        }

        private void createExcel()
        {
            Excel.Application excelApp = null;
            Excel.Workbook workbook = null;
            Excel.Sheets sheets = null;
            Excel.Worksheet newSheet = null;

            try
            {
                FileInfo file = new FileInfo(fileLoc);
                if (file.Exists)
                {
                    excelApp = new Excel.Application();
                    workbook = excelApp.Workbooks.Open(fileLoc, 0, false, 5, "", "",
                                                        false, XlPlatform.xlWindows, "",
                                                        true, false, 0, true, false, false);

                    sheets = workbook.Sheets;

                    //check columns exist
                    foreach (Excel.Worksheet sheet in sheets)
                    {
                        Console.WriteLine(sheet.Name);
                        sheet.Select(Type.Missing);

                        System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
                    }

                    newSheet = (Worksheet)sheets.Add(sheets[1], Type.Missing, Type.Missing, Type.Missing);
                    newSheet.Name = "My New Sheet";
                    newSheet.Cells[1, 1] = "BOO!";

                    workbook.Save();
                    workbook.Close(null, null, null);
                    excelApp.Quit();
                }
            }
            finally
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(newSheet);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(sheets);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(excelApp);

                newSheet = null;
                sheets = null;
                workbook = null;
                excelApp = null;

                GC.Collect();
            }
        }
    }
}

Thank you for all your help.

How do I generate random number for each row in a TSQL Select?

    DROP VIEW IF EXISTS vwGetNewNumber;
    GO
    Create View vwGetNewNumber
    as
    Select CAST(RAND(CHECKSUM(NEWID())) * 62 as INT) + 1 as NextID,
    'abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'as alpha_num;

    ---------------CTDE_GENERATE_PUBLIC_KEY -----------------
    DROP FUNCTION IF EXISTS CTDE_GENERATE_PUBLIC_KEY;  
    GO
    create function CTDE_GENERATE_PUBLIC_KEY()
    RETURNS NVARCHAR(32)
    AS 
    BEGIN
        DECLARE @private_key NVARCHAR(32);
        set @private_key = dbo.CTDE_GENERATE_32_BIT_KEY();
        return @private_key;
    END;
    go

---------------CTDE_GENERATE_32_BIT_KEY -----------------
DROP FUNCTION IF EXISTS CTDE_GENERATE_32_BIT_KEY;  
GO
CREATE function CTDE_GENERATE_32_BIT_KEY()
RETURNS NVARCHAR(32)
AS 
BEGIN
    DECLARE @public_key NVARCHAR(32);
    DECLARE @alpha_num NVARCHAR(62);
    DECLARE @start_index INT = 0;
    DECLARE @i INT = 0;
    select top 1 @alpha_num = alpha_num from vwGetNewNumber;
        WHILE @i < 32
        BEGIN
          select top 1 @start_index = NextID from vwGetNewNumber;
          set @public_key = concat (substring(@alpha_num,@start_index,1),@public_key);
          set @i = @i + 1;
        END;
    return @public_key;
END;
    select dbo.CTDE_GENERATE_PUBLIC_KEY() public_key;

How to get input field value using PHP

Use PHP's $_POST or $_GET superglobals to retrieve the value of the input tag via the name of the HTML tag.

For Example, change the method in your form and then echo out the value by the name of the input:

Using $_GET method:

<form name="form" action="" method="get">
  <input type="text" name="subject" id="subject" value="Car Loan">
</form>

To show the value:

<?php echo $_GET['subject']; ?>

Using $_POST method:

<form name="form" action="" method="post">
  <input type="text" name="subject" id="subject" value="Car Loan">
</form>

To show the value:

<?php echo $_POST['subject']; ?>

React-Router: No Not Found Route?

With the new version of React Router (using 2.0.1 now), you can use an asterisk as a path to route all 'other paths'.

So it would look like this:

<Route route="/" component={App}>
    <Route path=":area" component={Area}>
        <Route path=":city" component={City} />
        <Route path=":more-stuff" component={MoreStuff} />    
    </Route>
    <Route path="*" component={NotFoundRoute} />
</Route>

How does a Linux/Unix Bash script know its own PID?

In addition to the example given in the Advanced Bash Scripting Guide referenced by Jefromi, these examples show how pipes create subshells:

$ echo $$ $BASHPID | cat -
11656 31528
$ echo $$ $BASHPID
11656 11656
$ echo $$ | while read line; do echo $line $$ $BASHPID; done
11656 11656 31497
$ while read line; do echo $line $$ $BASHPID; done <<< $$
11656 11656 11656

Python - Locating the position of a regex match in a string?

I don't think this question has been completely answered yet because all of the answers only give single match examples. The OP's question demonstrates the nuances of having 2 matches as well as a substring match which should not be reported because it is not a word/token.

To match multiple occurrences, one might do something like this:

iter = re.finditer(r"\bis\b", String)
indices = [m.start(0) for m in iter]

This would return a list of the two indices for the original string.

What is the "right" JSON date format?

If you are using Kotlin then this will solve your problem. (MS Json format)

val dataString = "/Date(1586583441106)/"
val date = Date(Long.parseLong(dataString.substring(6, dataString.length - 2)))

ssh-copy-id no identities found error

Actually issues in one of Ubuntu machine is ssh-keygen command was not run properly. I tried running again and navigated into /home/user1/.ssh and able to see id_rsa and id_rsa.pub keys. then tried command ssh-copy-id and it was working fine.

rm: cannot remove: Permission denied

The code says everything:

max@serv$ chmod 777 .

Okay, it doesn't say everything.

In UNIX and Linux, the ability to remove a file is not determined by the access bits of that file. It is determined by the access bits of the directory which contains the file.

Think of it this way -- deleting a file doesn't modify that file. You aren't writing to the file, so why should "w" on the file matter? Deleting a file requires editing the directory that points to the file, so you need "w" on the that directory.

Eclipse doesn't stop at breakpoints

I had the same problem when I was using Eclipse Juno.. I installed Eclipse Indigo and it works fine. Try to reinstall eclipse.

Remove multiple objects with rm()

Another variation you can try is(expanding @mnel's answer) if you have many temp'x'.

here "n" could be the number of temp variables present

rm(list = c(paste("temp",c(1:n),sep="")))

NUnit Unit tests not showing in Test Explorer with Test Adapter installed

In my situation the 'NUnit3 Test Adapter' has been disabled. To re-enable it go to menu

Tools->Extensions and Updates...

On the left side select 'Installed'->'All'.

On the upper right corner search for 'nunit'.

If you have 'NUnit3 Test Adapter' installed, with the found item you can enable/disable it.

enter image description here

How do I set response headers in Flask?

We can set the response headers in Python Flask application using Flask application context using flask.g

This way of setting response headers in Flask application context using flask.g is thread safe and can be used to set custom & dynamic attributes from any file of application, this is especially helpful if we are setting custom/dynamic response headers from any helper class, that can also be accessed from any other file ( say like middleware, etc), this flask.g is global & valid for that request thread only.

Say if i want to read the response header from another api/http call that is being called from this app, and then extract any & set it as response headers for this app.

Sample Code: file: helper.py

import flask
from flask import request, g
from multidict import CIMultiDict
from asyncio import TimeoutError as HttpTimeout
from aiohttp import ClientSession

    def _extract_response_header(response)
      """
      extracts response headers from response object 
      and stores that required response header in flask.g app context
      """
      headers = CIMultiDict(response.headers)
      if 'my_response_header' not in g:
        g.my_response_header= {}
        g.my_response_header['x-custom-header'] = headers['x-custom-header']


    async def call_post_api(post_body):
      """
      sample method to make post api call using aiohttp clientsession
      """
      try:
        async with ClientSession() as session:
          async with session.post(uri, headers=_headers, json=post_body) as response:
            responseResult = await response.read()
            _extract_headers(response, responseResult)
            response_text = await response.text()
      except (HttpTimeout, ConnectionError) as ex:
        raise HttpTimeout(exception_message)

file: middleware.py

import flask
from flask import request, g

class SimpleMiddleWare(object):
    """
    Simple WSGI middleware
    """

    def __init__(self, app):
        self.app = app
        self._header_name = "any_request_header"

    def __call__(self, environ, start_response):
        """
        middleware to capture request header from incoming http request
        """
        request_id_header = environ.get(self._header_name)
        environ[self._header_name] = request_id_header

        def new_start_response(status, response_headers, exc_info=None):
            """
            set custom response headers
            """
            # set the request header as response header
            response_headers.append((self._header_name, request_id_header))
            # this is trying to access flask.g values set in helper class & set that as response header
            values = g.get(my_response_header, {})
            if values.get('x-custom-header'):
                response_headers.append(('x-custom-header', values.get('x-custom-header')))
            return start_response(status, response_headers, exc_info)

        return self.app(environ, new_start_response)

Calling the middleware from main class

file : main.py

from flask import Flask
import asyncio
from gevent.pywsgi import WSGIServer
from middleware import SimpleMiddleWare

    app = Flask(__name__)
    app.wsgi_app = SimpleMiddleWare(app.wsgi_app)

JQuery Bootstrap Multiselect plugin - Set a value as selected in the multiselect dropdown

I got a better solution from jquery-multiselect documentation.

var data = [101,102];

$("#data").multiSelect('deselect_all');

$("#data").multiSelect("select",data);

How to determine if a number is positive or negative?

if (((Double)calcYourDouble()).toString().contains("-"))
        doThis();
else doThat();

How to loop through all elements of a form jQuery

$('#new_user_form :input') should be your way forward. Note the omission of the > selector. A valid HTML form wouldn't allow for a input tag being a direct child of a form tag.

docker: Error response from daemon: Get https://registry-1.docker.io/v2/: Service Unavailable. IN DOCKER , MAC

I had the following entries in my /etc/hosts file:

34.228.211.243  registry-1.docker.io
34.205.88.205   auth.docker.io
104.18.121.25   production.cloudflare.docker.com

Just by commenting them out, I fixed the problem.

Convert a String representation of a Dictionary to a dictionary?

Use json. the ast library consumes a lot of memory and and slower. I have a process that needs to read a text file of 156Mb. Ast with 5 minutes delay for the conversion dictionary json and 1 minutes using 60% less memory!

Disable vertical scroll bar on div overflow: auto

How about a shorthand notation?

{overflow: auto hidden;}

Convert byte to string in Java

you can use

the character equivalent to 0x63 is 'c' but byte equivalent to it is 99

System.out.println("byte "+(char)0x63); 

Basic HTTP and Bearer Token Authentication

With nginx you can send both tokens like this (even though it's against the standard):

Authorization: Basic basic-token,Bearer bearer-token

This works as long as the basic token is first - nginx successfully forwards it to the application server.

And then you need to make sure your application can properly extract the Bearer from the above string.

jQuery .scrollTop(); + animation

Try this instead:

var body = $("body, html");
var top = body.scrollTop() // Get position of the body
if(top!=0)
{
       body.animate({scrollTop :0}, 500,function(){
         //DO SOMETHING AFTER SCROLL ANIMATION COMPLETED
          alert('Hello');
      });
}

Deploying my application at the root in Tomcat

You have a couple of options:

  1. Remove the out-of-the-box ROOT/ directory from tomcat and rename your war file to ROOT.war before deploying it.

  2. Deploy your war as (from your example) war_name.war and configure the context root in conf/server.xml to use your war file :

    <Context path="" docBase="war_name" debug="0" reloadable="true"></Context>
    

The first one is easier, but a little more kludgy. The second one is probably the more elegant way to do it.

How do I vertically center an H1 in a div?

This is the jQuery method. Looks like overkill but it calculates the offset.

<html>
<head>
<title></title>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
    <script type="text/javascript" src="https://raw.github.com/dreamerslab/jquery.center/master/jquery.center.js"></script>
    <script type="text/javascript">
        $(function(){

            $('#jquery-center').center();

        });
    </script>

</head>
<body>
    <div id="jquery-center" style="position:absolute;">
       <h1>foo</h1>
    </div>
</body>
</html>

How can I close a browser window without receiving the "Do you want to close this window" prompt?

The best solution I have found is:

this.focus();
self.opener=this;
self.close();

How to get the new value of an HTML input after a keypress has modified it?

Can you post your code? I'm not finding any issue with this. Tested on Firefox 3.01/safari 3.1.2 with:

function showMe(e) {
// i am spammy!
  alert(e.value);
}
....
<input type="text" id="foo" value="bar" onkeyup="showMe(this)" />

Jquery change <p> text programmatically

"saving" is something wholly different from changing paragraph content with jquery.

If you need to save changes you will have to write them to your server somehow (likely form submission along with all the security and input sanitizing that entails). If you have information that is saved on the server then you are no longer changing the content of a paragraph, you are drawing a paragraph with dynamic content (either from a database or a file which your server altered when you did the "saving").

Judging by your question, this is a topic on which you will have to do MUCH more research.

Input page (input.html):

<form action="/saveMyParagraph.php">
    <input name="pContent" type="text"></input>
</form>

Saving page (saveMyParagraph.php) and Ouput page (output.php):

Inserting Data Into a MySQL Database using PHP

Extract data from log file in specified range of time

Use grep and regular expressions, for example if you want 4 minutes interval of logs:

grep "31/Mar/2002:19:3[1-5]" logfile

will return all logs lines between 19:31 and 19:35 on 31/Mar/2002. Supposing you need the last 5 days starting from today 27/Sep/2011 you may use the following:

grep "2[3-7]/Sep/2011" logfile

Chrome violation : [Violation] Handler took 83ms of runtime

"Chrome violations" don't represent errors in either Chrome or your own web app. They are instead warnings to help you improve your app. In this case, Long running JavaScript and took 83ms of runtime are alerting you there's probably an opportunity to speed up your script.

("Violation" is not the best terminology; it's used here to imply the script "violates" a pre-defined guideline, but "warning" or similar would be clearer. These messages first appeared in Chrome in early 2017 and should ideally have a "More info" prompt to elaborate on the meaning and give suggested actions to the developer. Hopefully those will be added in the future.)

Multiple conditions in an IF statement in Excel VBA

In VBA we can not use if jj = 5 or 6 then we must use if jj = 5 or jj = 6 then

maybe this:

If inputWks.Range("d9") > 0 And (inputWks.Range("d11") = "Restricted_Expenditure" Or inputWks.Range("d11") = "Unrestricted_Expenditure") Then

In PHP, how do you change the key of an array element?

One which preservers ordering that's simple to understand:

function rename_array_key(array $array, $old_key, $new_key) {
  if (!array_key_exists($old_key, $array)) {
      return $array;
  }
  $new_array = [];
  foreach ($array as $key => $value) {
    $new_key = $old_key === $key
      ? $new_key
      : $key;
    $new_array[$new_key] = $value;
  }
  return $new_array;
}

Simple prime number generator in Python

Just studied the topic, look for the examples in the thread and try to make my version:

from collections import defaultdict
# from pprint import pprint

import re


def gen_primes(limit=None):
    """Sieve of Eratosthenes"""
    not_prime = defaultdict(list)
    num = 2
    while limit is None or num <= limit:
        if num in not_prime:
            for prime in not_prime[num]:
                not_prime[prime + num].append(prime)
            del not_prime[num]
        else:  # Prime number
            yield num
            not_prime[num * num] = [num]
        # It's amazing to debug it this way:
        # pprint([num, dict(not_prime)], width=1)
        # input()
        num += 1


def is_prime(num):
    """Check if number is prime based on Sieve of Eratosthenes"""
    return num > 1 and list(gen_primes(limit=num)).pop() == num


def oneliner_is_prime(num):
    """Simple check if number is prime"""
    return num > 1 and not any([num % x == 0 for x in range(2, num)])


def regex_is_prime(num):
    return re.compile(r'^1?$|^(11+)\1+$').match('1' * num) is None


def simple_is_prime(num):
    """Simple check if number is prime
    More efficient than oneliner_is_prime as it breaks the loop
    """
    for x in range(2, num):
        if num % x == 0:
            return False
    return num > 1


def simple_gen_primes(limit=None):
    """Prime number generator based on simple gen"""
    num = 2
    while limit is None or num <= limit:
        if simple_is_prime(num):
            yield num
        num += 1


if __name__ == "__main__":
    less1000primes = list(gen_primes(limit=1000))
    assert less1000primes == list(simple_gen_primes(limit=1000))
    for num in range(1000):
        assert (
            (num in less1000primes)
            == is_prime(num)
            == oneliner_is_prime(num)
            == regex_is_prime(num)
            == simple_is_prime(num)
        )
    print("Primes less than 1000:")
    print(less1000primes)

    from timeit import timeit

    print("\nTimeit:")
    print(
        "gen_primes:",
        timeit(
            "list(gen_primes(limit=1000))",
            setup="from __main__ import gen_primes",
            number=1000,
        ),
    )
    print(
        "simple_gen_primes:",
        timeit(
            "list(simple_gen_primes(limit=1000))",
            setup="from __main__ import simple_gen_primes",
            number=1000,
        ),
    )
    print(
        "is_prime:",
        timeit(
            "[is_prime(num) for num in range(2, 1000)]",
            setup="from __main__ import is_prime",
            number=100,
        ),
    )
    print(
        "oneliner_is_prime:",
        timeit(
            "[oneliner_is_prime(num) for num in range(2, 1000)]",
            setup="from __main__ import oneliner_is_prime",
            number=100,
        ),
    )
    print(
        "regex_is_prime:",
        timeit(
            "[regex_is_prime(num) for num in range(2, 1000)]",
            setup="from __main__ import regex_is_prime",
            number=100,
        ),
    )
    print(
        "simple_is_prime:",
        timeit(
            "[simple_is_prime(num) for num in range(2, 1000)]",
            setup="from __main__ import simple_is_prime",
            number=100,
        ),
    )

The result of running this code show interesting results:

$ python prime_time.py
Primes less than 1000:
[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997]

Timeit:
gen_primes: 0.6738066330144648
simple_gen_primes: 4.738092333020177
is_prime: 31.83770858097705
oneliner_is_prime: 3.3708438930043485
regex_is_prime: 8.692703998007346
simple_is_prime: 0.4686249239894096

So I can see that we have right answers for different questions here; for a prime number generator gen_primes looks like the right answer; but for a prime number check, the simple_is_prime function is better suited.

This works, but I am always open to better ways to make is_prime function.

Oracle database: How to read a BLOB?

If the content is not too large, you can also use

SELECT CAST ( <blobfield> AS RAW( <maxFieldLength> ) ) FROM <table>;

or

SELECT DUMP ( CAST ( <blobfield> AS RAW( <maxFieldLength> ) ) ) FROM <table>;

This will show you the HEX values.

How to change permissions for a folder and its subfolders/files in one step?

For already created files:

find . \( -type f -exec chmod g=r,o=r {} \; \) , \( -type d -exec chmod g=rx,o=rx {} \; \)

For future created files:

sudo nano /etc/profile

And set:

umask 022

Common modes are:

  • 077: u=rw,g=,o=
  • 007: u=rw,g=rw,o=
  • 022: u=rw,g=r,o=r
  • 002: u=rw,g=rw,o=r

How to append the output to a file?

Use >> to append:

command >> file

What does this mean? "Parse error: syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM"

Just my two cents for future visitors who have this problem.

This is the correct syntax for PHP 5.3, for example if you call static method from the class name:

MyClassName::getConfig($key);

If you previously assign the ClassName to the $cnf variable, you can call the static method from it (we are talking about PHP 5.3):

$cnf = MyClassName;
$cnf::getConfig($key);

However, this sintax doesn't work on PHP 5.2 or lower, and you need to use the following:

$cnf = MyClassName;
call_user_func(array($cnf, "getConfig", $key, ...otherposibleadditionalparameters... ));

Hope this helps people having this error in 5.2 version (don't know if this was openfrog's version).

Make ABC Ordered List Items Have Bold Style

You could do something like this also:

ol {
  font-weight: bold;
}

ol > li > * {
  font-weight: normal;
}

So you have no "style" attributes in your HTML

Understanding the Gemfile.lock file

Bundler is a Gem manager which provides a consistent environment for Ruby projects by tracking and installing the exact gems and versions that are needed.

Gemfile and Gemfile.lock are primary products given by Bundler gem (Bundler itself is a gem).

Gemfile contains your project dependency on gem(s), that you manually mention with version(s) specified, but those gem(s) inturn depends on other gem(s) which is resolved by bundler automatically.

Gemfile.lock contain complete snapshot of all the gem(s) in Gemfile along with there associated dependency.

When you first call bundle install, it will create this Gemfile.lock and uses this file in all subsequent calls to bundle install, which ensures that you have all the dependencies installed and will skip dependency installation.

Same happens when you share your code with different machines

You share your Gemfile.lock along with Gemfile, when you run bundle install on other machine it will refer to your Gemfile.lock and skip dependency resolution step, instead it will install all of the same dependent gem(s) that you used on the original machine, which maintains consistency across multiple machines

Why do we need to maintain consistency along multiple machines ?

  • Running different versions on different machines could lead to broken code

  • Suppose, your app used the version 1.5.3 and it works 14 months ago
    without any problems, and you try to install on different machine
    without Gemfile.lock now you get the version 1.5.8. Maybe it's broken with the latest version of some gem(s) and your application will
    fail. Maintaining consistency is of utmost importance (preferred
    practice).

It is also possible to update gem(s) in Gemfile.lock by using bundle update.

This is based on the concept of conservative updating

How do I compare 2 rows from the same table (SQL Server)?

OK, after 2 years it's finally time to correct the syntax:

SELECT  t1.value, t2.value
FROM    MyTable t1
JOIN    MyTable t2
ON      t1.id = t2.id
WHERE   t1.id = @id
        AND t1.status = @status1
        AND t2.status = @status2

load external css file in body tag

No, it is not okay to put a link element in the body tag. See the specification (links to the HTML4.01 specs, but I believe it is true for all versions of HTML):

“This element defines a link. Unlike A, it may only appear in the HEAD section of a document, although it may appear any number of times.”

How to fix a collation conflict in a SQL Server query?

I had problems with collations as I had most of the tables with Modern_Spanish_CI_AS, but a few, which I had inherited or copied from another Database, had SQL_Latin1_General_CP1_CI_AS collation.

In my case, the easiest way to solve the problem has been as follows:

  1. I've created a copy of the tables which were 'Latin American, using script table as...
  2. The new tables have obviously acquired the 'Modern Spanish' collation of my database
  3. I've copied the data of my 'Latin American' table into the new one, deleted the old one and renamed the new one.

I hope this helps other users.

DataColumn Name from DataRow (not DataTable)

You need something like this:

foreach(DataColumn c in dr.Table.Columns)
{
  MessageBox.Show(c.ColumnName);
}

The SELECT permission was denied on the object 'sysobjects', database 'mssqlsystemresource', schema 'sys'

I solved this by referring properties of login user under the security, logins. then go to User Mapping and select the database then check db_datareader and db_dataweriter options.

Git: which is the default configured remote for branch?

For the sake of completeness: the previous answers tell how to set the upstream branch, but not how to see it.

There are a few ways to do this:

git branch -vv shows that info for all branches. (formatted in blue in most terminals)

cat .git/config shows this also.

For reference:

ReactJS: "Uncaught SyntaxError: Unexpected token <"

Add type="text/babel" to the script that includes the .jsx file and add this: <script src="https://npmcdn.com/[email protected]/browser.min.js"></script>

React Native android build failed. SDK location not found

If local.properties file is missing, just create one in the "project/android" folder with 'sdk.dir=/Users/apple/Library/Android/sdk' and make sure your SDK in on that location.

for creating a file with custom extensions on mac refer the following link

How do I save a TextEdit (mac) file with a custom extension (.sas)?

jQuery Cross Domain Ajax

The response from server is JSON String format. If the set dataType as 'json' jquery will attempt to use it directly. You need to set dataType as 'text' and then parse it manually.

$.ajax({
    type: 'GET',
    dataType: "text", // You need to use dataType text else it will try to parse it.
    url: "http://someotherdomain.com/service.svc",
    success: function (responseData, textStatus, jqXHR) {
        console.log("in");
        var data = JSON.parse(responseData['AuthenticateUserResult']);
        console.log(data);
    },
    error: function (responseData, textStatus, errorThrown) {
        alert('POST failed.');
    }
});

How does Python manage int and long?

Interesting. On my 64-bit (i7 Ubuntu) box:

>>> print type(0x7FFFFFFF)
<type 'int'>
>>> print type(0x7FFFFFFF+1)
<type 'int'>

Guess it steps up to 64 bit ints on a larger machine.

Getting Excel to refresh data on sheet from within VBA

Sometimes Excel will hiccup and needs a kick-start to reapply an equation. This happens in some cases when you are using custom formulas.

Make sure that you have the following script

ActiveSheet.EnableCalculation = True

Reapply the equation of choice.

Cells(RowA,ColB).Formula = Cells(RowA,ColB).Formula

This can then be looped as needed.

return results from a function (javascript, nodejs)

You are trying to execute an asynchronous function in a synchronous way, which is unfortunately not possible in Javascript.

As you guessed correctly, the roomId=results.... is executed when the loading from the DB completes, which is done asynchronously, so AFTER the resto of your code is completed.

Look at this article, it talks about .insert and not .find, but the idea is the same : http://metaduck.com/01-asynchronous-iteration-patterns.html

Objective C - Assign, Copy, Retain

NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:@"First",@"Second", nil];
NSMutableArray *copiedArray = [array mutableCopy];
NSMutableArray *retainedArray = [array retain];

[retainedArray addObject:@"Retained Third"];
[copiedArray addObject:@"Copied Third"];

NSLog(@"array = %@",array);
NSLog(@"Retained Array = %@",retainedArray);
NSLog(@"Copied Array = %@",copiedArray);

array = (
    First,
    Second,
    "Retained Third"
)
Retained Array = (
    First,
    Second,
    "Retained Third"
)
Copied Array = (
    First,
    Second,
    "Copied Third"
)

SVG rounded corner

As referenced in my answer to Applying rounded corners to paths/polygons, I have written a routine in javascript for generically rounding corners of SVG paths, with examples, here: http://plnkr.co/edit/kGnGGyoOCKil02k04snu.

It will work independently from any stroke effects you may have. To use, include the rounding.js file from the Plnkr and call the function like so:

roundPathCorners(pathString, radius, useFractionalRadius)

The result will be the rounded path.

The results look like this:

SVG Path Rounding Examples

What's the scope of a variable initialized in an if statement?

Yes, they're in the same "local scope", and actually code like this is common in Python:

if condition:
  x = 'something'
else:
  x = 'something else'

use(x)

Note that x isn't declared or initialized before the condition, like it would be in C or Java, for example.

In other words, Python does not have block-level scopes. Be careful, though, with examples such as

if False:
    x = 3
print(x)

which would clearly raise a NameError exception.

What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how can I ensure it doesn't?

If you want to make sure that newly created projects or imported projects in Eclipse use another default java version than Java 1.5, you can change the configuration in the maven-compiler-plugin.

  • Go to the folder .m2/repository/org/apache/maven/plugins/maven-compiler-plugin/3.1
  • Open maven-compiler-plugin-3.1.jar with a zip program.
  • Go to META-INF/maven and open the plugin.xml
  • In the following lines:
    <source implementation="java.lang.String" default-value="1.5">${maven.compiler.source}</source>
    <target implementation="java.lang.String" default-value="1.5">${maven.compiler.target}</target>

  • change the default-value to 1.6 or 1.8 or whatever you like.

  • Save the file and make sure it is written back to the zip file.

From now on all new Maven projects use the java version you specified.

Information is from the following blog post: https://sandocean.wordpress.com/2019/03/22/directly-generating-maven-projects-in-eclipse-with-java-version-newer-than-1-5/

Eclipse hangs on loading workbench

./eclipse -clean -refresh

as mentioned in comment by sulai Dec 20 '12 at 12:46, that worked for me.

However, on the Mac OS X, I had to figure out how to get to ./eclipse

Here's the solution:

cd Eclipse.app/Contents/MacOS/

Thank you Andrew's comment for this post: https://stackoverflow.com/a/1783448/2162226

How to copy a char array in C?

for integer types

#include <string.h>    

int array1[10] = {0,1,2,3,4,5,6,7,8,9};
int array2[10];


memcpy(array2,array1,sizeof(array1)); // memcpy("destination","source","size")

How to change value of process.env.PORT in node.js?

use the below command to set the port number in node process while running node JS programme:

set PORT =3000 && node file_name.js

The set port can be accessed in the code as

process.env.PORT 

How can I protect my .NET assemblies from decompilation?

We use {SmartAssembly} for .NET protection of an enterprise level distributed application, and it has worked great for us.

Catching an exception while using a Python 'with' statement

Differentiating between the possible origins of exceptions raised from a compound with statement

Differentiating between exceptions that occur in a with statement is tricky because they can originate in different places. Exceptions can be raised from either of the following places (or functions called therein):

  • ContextManager.__init__
  • ContextManager.__enter__
  • the body of the with
  • ContextManager.__exit__

For more details see the documentation about Context Manager Types.

If we want to distinguish between these different cases, just wrapping the with into a try .. except is not sufficient. Consider the following example (using ValueError as an example but of course it could be substituted with any other exception type):

try:
    with ContextManager():
        BLOCK
except ValueError as err:
    print(err)

Here the except will catch exceptions originating in all of the four different places and thus does not allow to distinguish between them. If we move the instantiation of the context manager object outside the with, we can distinguish between __init__ and BLOCK / __enter__ / __exit__:

try:
    mgr = ContextManager()
except ValueError as err:
    print('__init__ raised:', err)
else:
    try:
        with mgr:
            try:
                BLOCK
            except TypeError:  # catching another type (which we want to handle here)
                pass
    except ValueError as err:
        # At this point we still cannot distinguish between exceptions raised from
        # __enter__, BLOCK, __exit__ (also BLOCK since we didn't catch ValueError in the body)
        pass

Effectively this just helped with the __init__ part but we can add an extra sentinel variable to check whether the body of the with started to execute (i.e. differentiating between __enter__ and the others):

try:
    mgr = ContextManager()  # __init__ could raise
except ValueError as err:
    print('__init__ raised:', err)
else:
    try:
        entered_body = False
        with mgr:
            entered_body = True  # __enter__ did not raise at this point
            try:
                BLOCK
            except TypeError:  # catching another type (which we want to handle here)
                pass
    except ValueError as err:
        if not entered_body:
            print('__enter__ raised:', err)
        else:
            # At this point we know the exception came either from BLOCK or from __exit__
            pass

The tricky part is to differentiate between exceptions originating from BLOCK and __exit__ because an exception that escapes the body of the with will be passed to __exit__ which can decide how to handle it (see the docs). If however __exit__ raises itself, the original exception will be replaced by the new one. To deal with these cases we can add a general except clause in the body of the with to store any potential exception that would have otherwise escaped unnoticed and compare it with the one caught in the outermost except later on - if they are the same this means the origin was BLOCK or otherwise it was __exit__ (in case __exit__ suppresses the exception by returning a true value the outermost except will simply not be executed).

try:
    mgr = ContextManager()  # __init__ could raise
except ValueError as err:
    print('__init__ raised:', err)
else:
    entered_body = exc_escaped_from_body = False
    try:
        with mgr:
            entered_body = True  # __enter__ did not raise at this point
            try:
                BLOCK
            except TypeError:  # catching another type (which we want to handle here)
                pass
            except Exception as err:  # this exception would normally escape without notice
                # we store this exception to check in the outer `except` clause
                # whether it is the same (otherwise it comes from __exit__)
                exc_escaped_from_body = err
                raise  # re-raise since we didn't intend to handle it, just needed to store it
    except ValueError as err:
        if not entered_body:
            print('__enter__ raised:', err)
        elif err is exc_escaped_from_body:
            print('BLOCK raised:', err)
        else:
            print('__exit__ raised:', err)

Alternative approach using the equivalent form mentioned in PEP 343

PEP 343 -- The "with" Statement specifies an equivalent "non-with" version of the with statement. Here we can readily wrap the various parts with try ... except and thus differentiate between the different potential error sources:

import sys

try:
    mgr = ContextManager()
except ValueError as err:
    print('__init__ raised:', err)
else:
    try:
        value = type(mgr).__enter__(mgr)
    except ValueError as err:
        print('__enter__ raised:', err)
    else:
        exit = type(mgr).__exit__
        exc = True
        try:
            try:
                BLOCK
            except TypeError:
                pass
            except:
                exc = False
                try:
                    exit_val = exit(mgr, *sys.exc_info())
                except ValueError as err:
                    print('__exit__ raised:', err)
                else:
                    if not exit_val:
                        raise
        except ValueError as err:
            print('BLOCK raised:', err)
        finally:
            if exc:
                try:
                    exit(mgr, None, None, None)
                except ValueError as err:
                    print('__exit__ raised:', err)

Usually a simpler approach will do just fine

The need for such special exception handling should be quite rare and normally wrapping the whole with in a try ... except block will be sufficient. Especially if the various error sources are indicated by different (custom) exception types (the context managers need to be designed accordingly) we can readily distinguish between them. For example:

try:
    with ContextManager():
        BLOCK
except InitError:  # raised from __init__
    ...
except AcquireResourceError:  # raised from __enter__
    ...
except ValueError:  # raised from BLOCK
    ...
except ReleaseResourceError:  # raised from __exit__
    ...

How to parse data in JSON format?

Very simple:

import json
data = json.loads('{"one" : "1", "two" : "2", "three" : "3"}')
print data['two']

How do I make CMake output into a 'bin' dir?

$ cat CMakeLists.txt
project (hello)
set(EXECUTABLE_OUTPUT_PATH "bin")
add_executable (hello hello.c)

Android: combining text & image on a Button or ImageButton

This code works for me perfectly

<LinearLayout
    android:id="@+id/choosePhotosView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:gravity="center"
    android:clickable="true"
    android:background="@drawable/transparent_button_bg_rev_selector">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/choose_photo"/>

     <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@android:color/white"
        android:text="@string/choose_photos_tv"/>

</LinearLayout>

Add ArrayList to another ArrayList in java

Initiate the NodeList inside the for loop and you will get the desired output.

ArrayList<String> nodes = new ArrayList<String>();
 ArrayList list=new ArrayList();

        for(int i=0;i<PropertyNode.getLength()-1;i++){
            ArrayList NodeList=new ArrayList();
            Node childNode =  PropertyNode.item(i);
                NodeList Children = childNode.getChildNodes();

                if(Children!=null){
                    nodes.clear();
                    nodes.add("PropertyStart");
                    nodes.add(Children.item(3).getTextContent());
                    nodes.add(Children.item(7).getTextContent());
                    nodes.add(Children.item(9).getTextContent());
                    nodes.add(Children.item(11).getTextContent());
                    nodes.add(Children.item(13).getTextContent());
                    nodes.add("PropertyEnd");

                }   
                NodeList.addAll(nodes);
                list.add(NodeList);
        }

Explanation: NodeList is an object which remains same throughout the loop so adding same variable to list in a loop will actually add it only once. The loop is only adding its variables in single NodeList array hence you must be seeing

[/*list*/    [  /*NodeList*/   ]   ]

and NodeList contains [prostart, a,b,c,proend,prostart,d,e,f,proend ...]

Detect user scroll down or scroll up in jQuery

To differentiate between scroll up/down in jQuery, you could use:

var mousewheelevt = (/Firefox/i.test(navigator.userAgent)) ? "DOMMouseScroll" : "mousewheel" //FF doesn't recognize mousewheel as of FF3.x
$('#yourDiv').bind(mousewheelevt, function(e){

    var evt = window.event || e //equalize event object     
    evt = evt.originalEvent ? evt.originalEvent : evt; //convert to originalEvent if possible               
    var delta = evt.detail ? evt.detail*(-40) : evt.wheelDelta //check for detail first, because it is used by Opera and FF

    if(delta > 0) {
        //scroll up
    }
    else{
        //scroll down
    }   
});

This method also works in divs that have overflow:hidden.

I successfully tested it in FireFox, IE and Chrome.

scp with port number specified

Unlike ssh, scp uses the uppercase P switch to set the port instead of the lowercase p:

scp -P 80 ... # Use port 80 to bypass the firewall, instead of the scp default

The lowercase p switch is used with scp for the preservation of times and modes.

Here is an excerpt from scp's man page with all of the details concerning the two switches, as well as an explanation of why uppercase P was chosen for scp:

-P port   Specifies the port to connect to on the remote host. Note that this option is written with a capital 'P', because -p is already reserved for preserving the times and modes of the file in rcp(1).

-p           Preserves modification times, access times, and modes from the original file.

Update and aside to address one of the (heavily upvoted) comments:

With regard to Abdull's comment about scp option order, what he suggests:

scp -P80 -r some_directory -P 80 ...

..., intersperses options and parameters. getopt(1) clearly defines that parameters must come after options and not be interspersed with them:

The parameters getopt is called with can be divided into two parts: options which modify the way getopt will do the parsing (the options and the optstring in the SYNOPSIS), and the parameters which are to be parsed (parameters in the SYNOPSIS). The second part will start at the first non-option parameter that is not an option argument, or after the first occurrence of '--'. If no '-o' or '--options' option is found in the first part, the first parameter of the second part is used as the short options string.

Since the -r command line option takes no further arguments, some_directory is "the first non-option parameter that is not an option argument." Therefore, as clearly spelled out in the getopt(1) man page, all succeeding command line arguments that follow it (i.e., -P 80 ...) are assumed to be non-options (and non-option arguments).

So, in effect, this is how getopt(1) sees the example presented with the end of the options and the beginning of the parameters demarcated by succeeding text bing in gray:

scp -P80 -r some_directory -P 80 ...

This has nothing to do with scp behavior and everything to do with how POSIX standard applications parse command line options using the getopt(3) set of C functions.

For more details with regard to command line ordering and processing, please read the getopt(1) manpage using:

man 1 getopt

How can I schedule a job to run a SQL query daily?

  1. Expand the SQL Server Agent node and right click the Jobs node in SQL Server Agent and select 'New Job'

  2. In the 'New Job' window enter the name of the job and a description on the 'General' tab.

  3. Select 'Steps' on the left hand side of the window and click 'New' at the bottom.

  4. In the 'Steps' window enter a step name and select the database you want the query to run against.

  5. Paste in the T-SQL command you want to run into the Command window and click 'OK'.

  6. Click on the 'Schedule' menu on the left of the New Job window and enter the schedule information (e.g. daily and a time).

  7. Click 'OK' - and that should be it.

(There are of course other options you can add - but I would say that is the bare minimum you need to get a job set up and scheduled)

Latest jQuery version on Google's CDN

Here's an updated link.

There are updated now and then, just keep checking for the latest version.

gcc error: wrong ELF class: ELFCLASS64

You can specify '-m32' or '-m64' to select the compilation mode.

When dealing with autoconf (configure) scripts, I usually set CC="gcc -m64" (or CC="gcc -m32") in the environment so that everything is compiled with the correct bittiness. At least, usually...people find endless ways to make that not quite work, but my batting average is very high (way over 95%) with it.

How Can I Bypass the X-Frame-Options: SAMEORIGIN HTTP Header?

The X-Frame-Options header is a security feature enforced at the browser level.

If you have control over your user base (IT dept for corp app), you could try something like a greasemonkey script (if you can a) deploy greasemonkey across everyone and b) deploy your script in a shared way)...

Alternatively, you can proxy their result. Create an endpoint on your server, and have that endpoint open a connection to the target endpoint, and simply funnel traffic backwards.

How to return rows from left table not found in right table?

Try This

SELECT f.*
FROM first_table f LEFT JOIN second_table s ON f.key=s.key
WHERE s.key is NULL

For more please read this article : Joins in Sql Server

enter image description here

How to make links in a TextView clickable?

i used this simply

Linkify.addLinks(TextView, Linkify.ALL);

makes the links clickable given here

Python: Removing list element while iterating over list

You could always iterate over a copy of the list, leaving you free to modify the original:

for item in list(somelist):
  ...
  somelist.remove(item)

How can I list all foreign keys referencing a given table in SQL Server?

Working off of what @Gishu did I was able to produce and use the following SQL in SQL Server 2005

SELECT t.name AS TableWithForeignKey, fk.constraint_column_id AS FK_PartNo, 
       c.name AS ForeignKeyColumn, o.name AS FK_Name 
  FROM sys.foreign_key_columns AS fk
       INNER JOIN sys.tables AS t ON fk.parent_object_id = t.object_id
       INNER JOIN sys.columns AS c ON fk.parent_object_id = c.object_id 
                                  AND fk.parent_column_id = c.column_id
       INNER JOIN sys.objects AS o ON fk.constraint_object_id = o.object_id
  WHERE fk.referenced_object_id = (SELECT object_id FROM sys.tables 
                                        WHERE name = 'TableOthersForeignKeyInto')
  ORDER BY TableWithForeignKey, FK_PartNo;

Which Displays the tables, columns and Foreign Key names all in 1 query.

Table fixed header and scrollable body

In my eyes, one of the best plugins for jQuery is DataTables.

It also has an extension for fixed header, and it is very easily implemented.

Taken from their site:

HTML:

<table id="example" class="display" cellspacing="0" width="100%">
    <thead>
        <tr>
            <th>Name</th>
            <th>Position</th>
            <th>Office</th>
            <th>Age</th>
            <th>Start date</th>
            <th>Salary</th>
        </tr>
    </thead>

    <tfoot>
        <tr>
            <th>Name</th>
            <th>Position</th>
            <th>Office</th>
            <th>Age</th>
            <th>Start date</th>
            <th>Salary</th>
        </tr>
    </tfoot>

    <tbody>
        <tr>
            <td>Tiger Nixon</td>
            <td>System Architect</td>
            <td>Edinburgh</td>
            <td>61</td>
            <td>2011/04/25</td>
            <td>$320,800</td>
        </tr>
        <tr>
            <td>Garrett Winters</td>
            <td>Accountant</td>
            <td>Tokyo</td>
            <td>63</td>
            <td>2011/07/25</td>
            <td>$170,750</td>
        </tr>
        <tr>
            <td>Ashton Cox</td>
            <td>Junior Technical Author</td>
            <td>San Francisco</td>
            <td>66</td>
            <td>2009/01/12</td>
            <td>$86,000</td>
        </tr>
  </tbody>
</table>

JavaScript:

$(document).ready(function() {
    var table = $('#example').DataTable();

    new $.fn.dataTable.FixedHeader( table );
} );

But the simplest you can have for just making a scrollable <tbody> is:

//configure table with fixed header and scrolling rows
$('#example').DataTable({
    scrollY: 400,
    scrollCollapse: true,
    paging: false,
    searching: false,
    ordering: false,
    info: false
});

How to configure PHP to send e-mail?

You need to have a smtp service setup in your local machine in order to send emails. There are many available freely just search on google.

If you own a server or VPS upload the script and it will work fine.

serialize/deserialize java 8 java.time with Jackson JSON mapper

If you consider using fastjson, you can solve your problem, note the version

 <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>fastjson</artifactId>
        <version>1.2.56</version>
 </dependency>

What's the difference between utf8_general_ci and utf8_unicode_ci?

There are two big difference the sorting and the character matching:

Sorting:

  • utf8mb4_general_ci removes all accents and sorts one by one which may create incorrect sort results.
  • utf8mb4_unicode_ci sorts accurate.

Character Matching

They match characters differently.

For example, in utf8mb4_unicode_ci you have i != i, but in utf8mb4_general_ci it holds i=i.

For example, imagine you have a row with name="Yilmaz". Then

select id from users where name='Yilmaz';

would return the row if collocation is utf8mb4_general_ci, but if it is collocated with utf8mb4_unicode_ci it would not return the row!

On the other hand we have that a=ª and ß=ss in utf8mb4_unicode_ci which is not the case in utf8mb4_general_ci. So imagine you have a row with name="ªßi", then

select id from users where name='assi';

would return the row if collocation is utf8mb4_unicode_ci, but would not return a row if collocation is set to utf8mb4_general_ci.

A full list of matches for each collocation may be found here.

TypeError: sequence item 0: expected string, int found

Although the given list comprehension / generator expression answers are ok, I find this easier to read and understand:

values = ','.join(map(str, value_list))

How to scroll to bottom in a ScrollView on activity startup

After initializing your UI component and fill it with data. add those line to your on create method

Runnable runnable=new Runnable() {
        @Override
        public void run() {
            scrollView.fullScroll(ScrollView.FOCUS_DOWN);
        }
    };
    scrollView.post(runnable);

javascript get child by id

In modern browsers (IE8, Firefox, Chrome, Opera, Safari) you can use querySelector():

function test(el){
  el.querySelector("#child").style.display = "none";
}

For older browsers (<=IE7), you would have to use some sort of library, such as Sizzle or a framework, such as jQuery, to work with selectors.

As mentioned, IDs are supposed to be unique within a document, so it's easiest to just use document.getElementById("child").

Jackson Vs. Gson

I did this research the last week and I ended up with the same 2 libraries. As I'm using Spring 3 (that adopts Jackson in its default Json view 'JacksonJsonView') it was more natural for me to do the same. The 2 lib are pretty much the same... at the end they simply map to a json file! :)

Anyway as you said Jackson has a + in performance and that's very important for me. The project is also quite active as you can see from their web page and that's a very good sign as well.

PHP Unset Array value effect on other indexes

The keys are not shuffled or renumbered. The unset() key is simply removed and the others remain.

$a = array(1,2,3,4,5);
unset($a[2]);
print_r($a);

Array
(
    [0] => 1
    [1] => 2
    [3] => 4
    [4] => 5
)

Resize image in the wiki of GitHub using Markdown

Updated:

Markdown syntax for images (external/internal):

![test](https://github.com/favicon.ico)

HTML code for sizing images (internal/external):

<img src="https://github.com/favicon.ico" width="48">

Example:

test


Old Answer:

This should work:

[[ http://url.to/image.png | height = 100px ]]

Source: https://guides.github.com/features/mastering-markdown/

How to convert integer to decimal in SQL Server query?

SELECT CAST(height AS DECIMAL(18,0)) / 10

Edit: How this works under the hood?

The result type is the same as the type of both arguments, or, if they are different, it is determined by the data type precedence table. You can therefore cast either argument to something non-integral.

Now DECIMAL(18,0), or you could equivalently write just DECIMAL, is still a kind of integer type, because that default scale of 0 means "no digits to the right of the decimal point". So a cast to it might in different circumstances work well for rounding to integers - the opposite of what we are trying to accomplish.

However, DECIMALs have their own rules for everything. They are generally non-integers, but always exact numerics. The result type of the DECIMAL division that we forced to occur is determined specially to be, in our case, DECIMAL(29,11). The result of the division will therefore be rounded to 11 places which is no concern for division by 10, but the rounding becomes observable when dividing by 3. You can control the amount of rounding by manipulating the scale of the left hand operand. You can also round more, but not less, by placing another ROUND or CAST operation around the whole expression.

Identical mechanics governs the simpler and nicer solution in the accepted answer:

  SELECT height / 10.0

In this case, the type of the divisor is DECIMAL(3,1) and the type of the result is DECIMAL(17,6). Try dividing by 3 and observe the difference in rounding.

If you just hate all this talk of precisions and scales, and just want SQL server to perform all calculations in good old double precision floating point arithmetics from some point on, you can force that, too:

SELECT height / CAST(10 AS FLOAT(53))

or equivalently just

SELECT height / CAST (10 AS FLOAT)

How can I cast int to enum?

I think to get a complete answer, people have to know how enums work internally in .NET.

How stuff works

An enum in .NET is a structure that maps a set of values (fields) to a basic type (the default is int). However, you can actually choose the integral type that your enum maps to:

public enum Foo : short

In this case the enum is mapped to the short data type, which means it will be stored in memory as a short and will behave as a short when you cast and use it.

If you look at it from a IL point of view, a (normal, int) enum looks like this:

.class public auto ansi serializable sealed BarFlag extends System.Enum
{
    .custom instance void System.FlagsAttribute::.ctor()
    .custom instance void ComVisibleAttribute::.ctor(bool) = { bool(true) }

    .field public static literal valuetype BarFlag AllFlags = int32(0x3fff)
    .field public static literal valuetype BarFlag Foo1 = int32(1)
    .field public static literal valuetype BarFlag Foo2 = int32(0x2000)

    // and so on for all flags or enum values

    .field public specialname rtspecialname int32 value__
}

What should get your attention here is that the value__ is stored separately from the enum values. In the case of the enum Foo above, the type of value__ is int16. This basically means that you can store whatever you want in an enum, as long as the types match.

At this point I'd like to point out that System.Enum is a value type, which basically means that BarFlag will take up 4 bytes in memory and Foo will take up 2 -- e.g. the size of the underlying type (it's actually more complicated than that, but hey...).

The answer

So, if you have an integer that you want to map to an enum, the runtime only has to do 2 things: copy the 4 bytes and name it something else (the name of the enum). Copying is implicit because the data is stored as value type - this basically means that if you use unmanaged code, you can simply interchange enums and integers without copying data.

To make it safe, I think it's a best practice to know that the underlying types are the same or implicitly convertible and to ensure the enum values exist (they aren't checked by default!).

To see how this works, try the following code:

public enum MyEnum : int
{
    Foo = 1,
    Bar = 2,
    Mek = 5
}

static void Main(string[] args)
{
    var e1 = (MyEnum)5;
    var e2 = (MyEnum)6;

    Console.WriteLine("{0} {1}", e1, e2);
    Console.ReadLine();
}

Note that casting to e2 also works! From the compiler perspective above this makes sense: the value__ field is simply filled with either 5 or 6 and when Console.WriteLine calls ToString(), the name of e1 is resolved while the name of e2 is not.

If that's not what you intended, use Enum.IsDefined(typeof(MyEnum), 6) to check if the value you are casting maps to a defined enum.

Also note that I'm explicit about the underlying type of the enum, even though the compiler actually checks this. I'm doing this to ensure I don't run into any surprises down the road. To see these surprises in action, you can use the following code (actually I've seen this happen a lot in database code):

public enum MyEnum : short
{
    Mek = 5
}

static void Main(string[] args)
{
    var e1 = (MyEnum)32769; // will not compile, out of bounds for a short

    object o = 5;
    var e2 = (MyEnum)o;     // will throw at runtime, because o is of type int

    Console.WriteLine("{0} {1}", e1, e2);
    Console.ReadLine();
}

How to JUnit test that two List<E> contain the same elements in the same order?

For excellent code-readability, Fest Assertions has nice support for asserting lists

So in this case, something like:

Assertions.assertThat(returnedComponents).containsExactly("One", "Two", "Three");

Or make the expected list to an array, but I prefer the above approach because it's more clear.

Assertions.assertThat(returnedComponents).containsExactly(argumentComponents.toArray());

Sharing a URL with a query string on Twitter

This will Work For You

http://twitter.com/share?text=text goes here&url=http://url goes here&hashtags=hashtag1,hashtag2,hashtag3

Here is a Live Example About it


http://twitter.com/share?text=Im Sharing on Twitter&url=https://stackoverflow.com/users/2943186/youssef-subehi&hashtags=stackoverflow,example,youssefusf

Compare if BigDecimal is greater than zero

It's as simple as:

if (value.compareTo(BigDecimal.ZERO) > 0)

The documentation for compareTo actually specifies that it will return -1, 0 or 1, but the more general Comparable<T>.compareTo method only guarantees less than zero, zero, or greater than zero for the appropriate three cases - so I typically just stick to that comparison.

How to copy a java.util.List into another java.util.List

re: indexOutOfBoundsException, your sublist args are the problem; you need to end the sublist at size-1. Being zero-based, the last element of a list is always size-1, there is no element in the size position, hence the error.

Using the Underscore module with Node.js

The Node REPL uses the underscore variable to hold the result of the last operation, so it conflicts with the Underscore library's use of the same variable. Try something like this:

Admin-MacBook-Pro:test admin$ node
> _und = require("./underscore-min")
{ [Function]
  _: [Circular],
  VERSION: '1.1.4',
  forEach: [Function],
  each: [Function],
  map: [Function],
  inject: [Function],
  (...more functions...)
  templateSettings: { evaluate: /<%([\s\S]+?)%>/g, interpolate: /<%=([\s\S]+?)%>/g },
  template: [Function] }
> _und.max([1,2,3])
3
> _und.max([4,5,6])
6

Ubuntu apt-get unable to fetch packages

If you're having the issue with VirtualBox and a Virtual Machine I fixed it by changing Settings -> Network -> Attached To from NAT to Bridged Adapter

How to execute command stored in a variable?

If you just do eval $cmd when we do cmd="ls -l" (interactively and in a script) we get the desired result. In your case, you have a pipe with a grep without a pattern, so the grep part will fail with an error message. Just $cmd will generate a "command not found" (or some such) message. So try use eval and use a finished command, not one that generates an error message.

How do I get the output of a shell command executed using into a variable from Jenkinsfile (groovy)?

All the above method will work. but to use the var as env variable inside your code you need to export the var first.

script{
  sh " 'shell command here' > command"
  command_var = readFile('command').trim()
  sh "export command_var=$command_var"
}

replace the shell command with the command of your choice. Now if you are using python code you can just specify os.getenv("command_var") that will return the output of the shell command executed previously.

Preserve Line Breaks From TextArea When Writing To MySQL

Got my own answer: Using this function from the data from the textarea solves the problem:

function mynl2br($text) { 
   return strtr($text, array("\r\n" => '<br />', "\r" => '<br />', "\n" => '<br />')); 
} 

More here: http://php.net/nl2br

Missing artifact com.oracle:ojdbc6:jar:11.2.0 in pom.xml

Due to Oracle license restriction, there are no public repositories that provide ojdbc jar.

You need to download it and install in your local repository. Get jar from Oracle and install it in your local maven repository using

mvn install:install-file -Dfile={path/to/your/ojdbc.jar} -DgroupId=com.oracle 
-DartifactId=ojdbc6 -Dversion=11.2.0 -Dpackaging=jar

If you are using ojdbc7, here is the link

Remove a folder from git tracking

I know this is an old thread but I just wanted to add a little as the marked solution didn't solve the problem for me (although I tried many times).

The only way I could actually stop git form tracking the folder was to do the following:

  1. Make a backup of the local folder and put in a safe place.
  2. Delete the folder from your local repo
  3. Make sure cache is cleared git rm -r --cached your_folder/
  4. Add your_folder/ to .gitignore
  5. Commit changes
  6. Add the backup back into your repo

You should now see that the folder is no longer tracked.

Don't ask me why just clearing the cache didn't work for me, I am not a Git super wizard but this is how I solved the issue.

An exception of type 'System.NullReferenceException' occurred in myproject.DLL but was not handled in user code

It means you have a null reference somewhere in there. Can you debug the app and stop the debugger when it gets here and investigate? Probably img1 is null or ConfigurationManager.AppSettings.Get("Url") is returning null.

lodash: mapping array to object

Another way with lodash

creating pairs, and then either construct a object or ES6 Map easily

_(params).map(v=>[v.name, v.input]).fromPairs().value()

or

_.fromPairs(params.map(v=>[v.name, v.input]))

Here is a working example

_x000D_
_x000D_
var params = [_x000D_
    { name: 'foo', input: 'bar' },_x000D_
    { name: 'baz', input: 'zle' }_x000D_
];_x000D_
_x000D_
var obj = _(params).map(v=>[v.name, v.input]).fromPairs().value();_x000D_
_x000D_
console.log(obj);
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script>
_x000D_
_x000D_
_x000D_

git submodule tracking latest

Edit (2020.12.28): GitHub change default master branch to main branch since October 2020. See https://github.com/github/renaming


Update March 2013

Git 1.8.2 added the possibility to track branches.

"git submodule" started learning a new mode to integrate with the tip of the remote branch (as opposed to integrating with the commit recorded in the superproject's gitlink).

# add submodule to track master branch
git submodule add -b master [URL to Git repo];

# update your submodule
git submodule update --remote 

If you had a submodule already present you now wish would track a branch, see "how to make an existing submodule track a branch".

Also see Vogella's tutorial on submodules for general information on submodules.

Note:

git submodule add -b . [URL to Git repo];
                    ^^^

See git submodule man page:

A special value of . is used to indicate that the name of the branch in the submodule should be the same name as the current branch in the current repository.


See commit b928922727d6691a3bdc28160f93f25712c565f6:

submodule add: If --branch is given, record it in .gitmodules

This allows you to easily record a submodule.<name>.branch option in .gitmodules when you add a new submodule. With this patch,

$ git submodule add -b <branch> <repository> [<path>]
$ git config -f .gitmodules submodule.<path>.branch <branch>

reduces to

$ git submodule add -b <branch> <repository> [<path>]

This means that future calls to

$ git submodule update --remote ...

will get updates from the same branch that you used to initialize the submodule, which is usually what you want.

Signed-off-by: W. Trevor King [email protected]


Original answer (February 2012):

A submodule is a single commit referenced by a parent repo.
Since it is a Git repo on its own, the "history of all commits" is accessible through a git log within that submodule.

So for a parent to track automatically the latest commit of a given branch of a submodule, it would need to:

  • cd in the submodule
  • git fetch/pull to make sure it has the latest commits on the right branch
  • cd back in the parent repo
  • add and commit in order to record the new commit of the submodule.

gitslave (that you already looked at) seems to be the best fit, including for the commit operation.

It is a little annoying to make changes to the submodule due to the requirement to check out onto the correct submodule branch, make the change, commit, and then go into the superproject and commit the commit (or at least record the new location of the submodule).

Other alternatives are detailed here.

How can jQuery deferred be used?

A deferred can be used in place of a mutex. This is essentially the same as the multiple ajax usage scenarios.

MUTEX

var mutex = 2;

setTimeout(function() {
 callback();
}, 800);

setTimeout(function() {
 callback();
}, 500);

function callback() {
 if (--mutex === 0) {
  //run code
 }
}

DEFERRED

function timeout(x) {
 var dfd = jQuery.Deferred();
 setTimeout(function() {
  dfd.resolve();
 }, x);
 return dfd.promise();
}

jQuery.when(
timeout(800), timeout(500)).done(function() {
 // run code
});

When using a Deferred as a mutex only, watch out for performance impacts (http://jsperf.com/deferred-vs-mutex/2). Though the convenience, as well as additional benefits supplied by a Deferred is well worth it, and in actual (user driven event based) usage the performance impact should not be noticeable.

gem install: Failed to build gem native extension (can't find header files)

Just to add path to ruby.h file in my PATH
for example:

export PATH=$PATH:/usr/src/ruby-xxxxxx

How can the Euclidean distance be calculated with NumPy?

I like np.dot (dot product):

a = numpy.array((xa,ya,za))
b = numpy.array((xb,yb,zb))

distance = (np.dot(a-b,a-b))**.5

Google server putty connect 'Disconnected: No supported authentication methods available (server sent: publickey)

I know this is an old question, but I had the same problem and solved it thanks to this answer.

I use Putty regularly and have never had any problems. I use and have always used public key authentication. Today I could not connect again to my server, without changing any settings.

Then I saw the answer and remembered that I inadvertently ran chmod 777 . in my user's home directory. I connected from somewhere else and simply ran chmod 755 ~. Everything was back to normal instantly, I didn't even have to restart sshd.

I hope I saved some time from someone

How can I get a character in a string by index?

Do you mean like this

int index = 2;
string s = "hello";
Console.WriteLine(s[index]);

string also implements IEnumberable<char> so you can also enumerate it like this

foreach (char c in s)
    Console.WriteLine(c);

How to change file encoding in NetBeans?

Go to etc folder in Netbeans home --> open netbeans.conf file and add on netbeans_default_options following line:

-J-Dfile.encoding=UTF-8

Restart Netbeans and it should be in UTF-8

To check go to help --> about and check System: Windows Vista version 6.0 running on x86; UTF-8; nl_NL (nb)

How to run a script as root on Mac OS X?

As in any unix-based environment, you can use the sudo command:

$ sudo script-name

It will ask for your password (your own, not a separate root password).

How to Retrieve value from JTextField in Java Swing?

How do we retrieve a value from a text field?

mytestField.getText();

ActionListner example:

mytextField.addActionListener(this);

public void actionPerformed(ActionEvent evt) {
    String text = textField.getText();
    textArea.append(text + newline);
    textField.selectAll();
}

How to solve munmap_chunk(): invalid pointer error in C++

This happens when the pointer passed to free() is not valid or has been modified somehow. I don't really know the details here. The bottom line is that the pointer passed to free() must be the same as returned by malloc(), realloc() and their friends. It's not always easy to spot what the problem is for a novice in their own code or even deeper in a library. In my case, it was a simple case of an undefined (uninitialized) pointer related to branching.

The free() function frees the memory space pointed to by ptr, which must have been returned by a previous call to malloc(), calloc() or realloc(). Otherwise, or if free(ptr) has already been called before, undefined behavior occurs. If ptr is NULL, no operation is performed. GNU 2012-05-10 MALLOC(3)

char *words; // setting this to NULL would have prevented the issue

if (condition) {
    words = malloc( 512 );

    /* calling free sometime later works here */

    free(words)
} else {

    /* do not allocate words in this branch */
}

/* free(words);  -- error here --
*** glibc detected *** ./bin: munmap_chunk(): invalid pointer: 0xb________ ***/

There are many similar questions here about the related free() and rellocate() functions. Some notable answers providing more details:

*** glibc detected *** free(): invalid next size (normal): 0x0a03c978 ***
*** glibc detected *** sendip: free(): invalid next size (normal): 0x09da25e8 ***
glibc detected, realloc(): invalid pointer


IMHO running everything in a debugger (Valgrind) is not the best option because errors like this are often caused by inept or novice programmers. It's more productive to figure out the issue manually and learn how to avoid it in the future.

How do I mock a class without an interface?

Most mocking frameworks (Moq and RhinoMocks included) generate proxy classes as a substitute for your mocked class, and override the virtual methods with behavior that you define. Because of this, you can only mock interfaces, or virtual methods on concrete or abstract classes. Additionally, if you're mocking a concrete class, you almost always need to provide a parameterless constructor so that the mocking framework knows how to instantiate the class.

Why the aversion to creating interfaces in your code?

SVN icon overlays not showing properly

My overlays disappeared all of a sudden (or so I thought). I came across this article https://corengen.wordpress.com/2014/07/30/my-tortoisesvn-icon-overlays-have-disappeared/ which points out that windows has 15 slots for overlay icons; 4 are reserved for windows, which leaves 11 for other applications. Regardless of how many overlay keys are in the registry, Windows selects the first 11 in alphabetical order.

When I upgraded Office, OneDrive added overlay icons -- prefixed with a lot of spaces -- pushing down Tortoise's overlays below the threshold: windows registry Since I am not using OneDrive, the solution was to add a "z" to the OneDrive key names.

Jquery: How to check if the element has certain css class/style

CSS Styles are key-value pairs, not just "tags". By default, each element has a full set of CSS styles assigned to it, most of them is implicitly using the browser defaults and some of them is explicitly redefined in CSS stylesheets.

To get the value assigned to a particular CSS entry of an element and compare it:

if ($('#yourElement').css('position') == 'absolute')
{
   // true
}

If you didn't redefine the style, you will get the browser default for that particular element.

Control flow in T-SQL SP using IF..ELSE IF - are there other ways?

Nope IF is the way to go, what is the problem you have with using it?

BTW your example won't ever get to the third block of code as it and the second block are exactly alike.

PHP is_numeric or preg_match 0-9 validation

is_numeric would accept "-0.5e+12" as a valid ID.

ARG or ENV, which one to use in this case?

So if want to set the value of an environment variable to something different for every build then we can pass these values during build time and we don't need to change our docker file every time.

While ENV, once set cannot be overwritten through command line values. So, if we want to have our environment variable to have different values for different builds then we could use ARG and set default values in our docker file. And when we want to overwrite these values then we can do so using --build-args at every build without changing our docker file.

For more details, you can refer this.

C# Wait until condition is true

Try this

void Function()
{
    while (condition) 
    {
        await Task.Delay(1);
    }
}

This will make the program wait until the condition is not true. You can just invert it by adding a "!" infront of the condition so that it will wait until the condition is true.

How to programmatically determine the current checked out Git branch

This one worked for me in the bash file.

git branch | grep '^*' | sed 's/* //'  


################bash file###################
#!/bin/bash
BRANCH=$(git branch | grep '^*' | sed 's/* //' )
echo $BRANCH

How do I add an integer value with javascript (jquery) to a value that's returning a string?

var month = new Date().getMonth();
var newmon = month + 1;
$('#month').html((newmon < 10 ? '0' : '') + newmon );

I simply fixed your month issue, getMonth array start from 0 to 11.

How to Create simple drag and Drop in angularjs

I just posted this to my brand spanking new blog: http://jasonturim.wordpress.com/2013/09/01/angularjs-drag-and-drop/

Code here: https://github.com/logicbomb/lvlDragDrop

Demo here: http://logicbomb.github.io/ng-directives/drag-drop.html

Here are the directives these rely on a UUID service which I've included below:

var module = angular.module("lvl.directives.dragdrop", ['lvl.services']);

module.directive('lvlDraggable', ['$rootScope', 'uuid', function($rootScope, uuid) {
        return {
            restrict: 'A',
            link: function(scope, el, attrs, controller) {
                console.log("linking draggable element");

                angular.element(el).attr("draggable", "true");
                var id = attrs.id;
                if (!attrs.id) {
                    id = uuid.new()
                    angular.element(el).attr("id", id);
                }

                el.bind("dragstart", function(e) {
                    e.dataTransfer.setData('text', id);

                    $rootScope.$emit("LVL-DRAG-START");
                });

                el.bind("dragend", function(e) {
                    $rootScope.$emit("LVL-DRAG-END");
                });
            }
        }
    }]);

module.directive('lvlDropTarget', ['$rootScope', 'uuid', function($rootScope, uuid) {
        return {
            restrict: 'A',
            scope: {
                onDrop: '&'
            },
            link: function(scope, el, attrs, controller) {
                var id = attrs.id;
                if (!attrs.id) {
                    id = uuid.new()
                    angular.element(el).attr("id", id);
                }

                el.bind("dragover", function(e) {
                  if (e.preventDefault) {
                    e.preventDefault(); // Necessary. Allows us to drop.
                  }

                  e.dataTransfer.dropEffect = 'move';  // See the section on the DataTransfer object.
                  return false;
                });

                el.bind("dragenter", function(e) {
                  // this / e.target is the current hover target.
                  angular.element(e.target).addClass('lvl-over');
                });

                el.bind("dragleave", function(e) {
                  angular.element(e.target).removeClass('lvl-over');  // this / e.target is previous target element.
                });

                el.bind("drop", function(e) {
                  if (e.preventDefault) {
                    e.preventDefault(); // Necessary. Allows us to drop.
                  }

                  if (e.stopPropagation) {
                    e.stopPropagation(); // Necessary. Allows us to drop.
                  }
                    var data = e.dataTransfer.getData("text");
                    var dest = document.getElementById(id);
                    var src = document.getElementById(data);

                    scope.onDrop({dragEl: src, dropEl: dest});
                });

                $rootScope.$on("LVL-DRAG-START", function() {
                    var el = document.getElementById(id);
                    angular.element(el).addClass("lvl-target");
                });

                $rootScope.$on("LVL-DRAG-END", function() {
                    var el = document.getElementById(id);
                    angular.element(el).removeClass("lvl-target");
                    angular.element(el).removeClass("lvl-over");
                });
            }
        }
    }]);

UUID service

angular
.module('lvl.services',[])
.factory('uuid', function() {
    var svc = {
        new: function() {
            function _p8(s) {
                var p = (Math.random().toString(16)+"000000000").substr(2,8);
                return s ? "-" + p.substr(0,4) + "-" + p.substr(4,4) : p ;
            }
            return _p8() + _p8(true) + _p8(true) + _p8();
        },

        empty: function() {
          return '00000000-0000-0000-0000-000000000000';
        }
    };

    return svc;
});

Among $_REQUEST, $_GET and $_POST which one is the fastest?

I'd suggest using $_POST and $_GET explicitly.

Using $_REQUEST should be unnecessary with proper site design anyway, and it comes with some downsides like leaving you open to easier CSRF/XSS attacks and other silliness that comes from storing data in the URL.

The speed difference should be minimal either way.

How to remove decimal part from a number in C#

Use Decimal.Truncate

It removes the fractional part from the decimal.

int i = (int)Decimal.Truncate(12.66m)

Including a .js file within a .js file

A popular method to tackle the problem of reducing JavaScript references from HTML files is by using a concatenation tool like Sprockets, which preprocesses and concatenates JavaScript source files together.

Apart from reducing the number of references from the HTML files, this will also reduce the number of hits to the server.

You may then want to run the resulting concatenation through a minification tool like jsmin to have it minified.

Generate JSON string from NSDictionary in iOS

Now no need third party classes ios 5 introduced Nsjsonserialization

NSString *urlString=@"Your url";
NSString *urlUTF8 = [urlString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *url=[[NSURL alloc]initWithString:urlUTF8];
NSURLRequest *request=[NSURLRequest requestWithURL:url];

NSURLResponse *response;

NSData *GETReply = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:nil];

NSError *myError = nil;

NSDictionary *res = [NSJSONSerialization JSONObjectWithData:GETReply options:NSJSONReadingMutableLeaves|| NSJSONReadingMutableContainers error:&myError];

Nslog(@"%@",res);

this code can useful for getting jsondata.