Programs & Examples On #Icq

ICQ is an instant messaging protocol and the name of its official client.

Why does C++ code for testing the Collatz conjecture run faster than hand-written assembly?

For the Collatz problem, you can get a significant boost in performance by caching the "tails". This is a time/memory trade-off. See: memoization (https://en.wikipedia.org/wiki/Memoization). You could also look into dynamic programming solutions for other time/memory trade-offs.

Example python implementation:

import sys

inner_loop = 0

def collatz_sequence(N, cache):
    global inner_loop

    l = [ ]
    stop = False
    n = N

    tails = [ ]

    while not stop:
        inner_loop += 1
        tmp = n
        l.append(n)
        if n <= 1:
            stop = True  
        elif n in cache:
            stop = True
        elif n % 2:
            n = 3*n + 1
        else:
            n = n // 2
        tails.append((tmp, len(l)))

    for key, offset in tails:
        if not key in cache:
            cache[key] = l[offset:]

    return l

def gen_sequence(l, cache):
    for elem in l:
        yield elem
        if elem in cache:
            yield from gen_sequence(cache[elem], cache)
            raise StopIteration

if __name__ == "__main__":
    le_cache = {}

    for n in range(1, 4711, 5):
        l = collatz_sequence(n, le_cache)
        print("{}: {}".format(n, len(list(gen_sequence(l, le_cache)))))

    print("inner_loop = {}".format(inner_loop))

UnexpectedRollbackException: Transaction rolled back because it has been marked as rollback-only

This is the normal behavior and the reason is that your sqlCommandHandlerService.persist method needs a TX when being executed (because it is marked with @Transactional annotation). But when it is called inside processNextRegistrationMessage, because there is a TX available, the container doesn't create a new one and uses existing TX. So if any exception occurs in sqlCommandHandlerService.persist method, it causes TX to be set to rollBackOnly (even if you catch the exception in the caller and ignore it).

To overcome this you can use propagation levels for transactions. Have a look at this to find out which propagation best suits your requirements.

Update; Read this!

Well after a colleague came to me with a couple of questions about a similar situation, I feel this needs a bit of clarification.
Although propagations solve such issues, you should be VERY careful about using them and do not use them unless you ABSOLUTELY understand what they mean and how they work. You may end up persisting some data and rolling back some others where you don't expect them to work that way and things can go horribly wrong.


EDIT Link to current version of the documentation

How to convert image into byte array and byte array to base64 String in android?

They have wrapped most stuff need to solve your problem, one of the tests looks like this:

String filename = CSSURLEmbedderTest.class.getResource("folder.png").getPath().replace("%20", " ");
String code = "background: url(folder.png);";

StringWriter writer = new StringWriter();
embedder = new CSSURLEmbedder(new StringReader(code), true);
embedder.embedImages(writer, filename.substring(0, filename.lastIndexOf("/")+1));

String result = writer.toString();
assertEquals("background: url(" + folderDataURI + ");", result);

How to put labels over geom_bar in R with ggplot2

As with many tasks in ggplot, the general strategy is to put what you'd like to add to the plot into a data frame in a way such that the variables match up with the variables and aesthetics in your plot. So for example, you'd create a new data frame like this:

dfTab <- as.data.frame(table(df))
colnames(dfTab)[1] <- "x"
dfTab$lab <- as.character(100 * dfTab$Freq / sum(dfTab$Freq))

So that the x variable matches the corresponding variable in df, and so on. Then you simply include it using geom_text:

ggplot(df) + geom_bar(aes(x,fill=x)) + 
    geom_text(data=dfTab,aes(x=x,y=Freq,label=lab),vjust=0) +
    opts(axis.text.x=theme_blank(),axis.ticks=theme_blank(),
        axis.title.x=theme_blank(),legend.title=theme_blank(),
        axis.title.y=theme_blank())

This example will plot just the percentages, but you can paste together the counts as well via something like this:

dfTab$lab <- paste(dfTab$Freq,paste("(",dfTab$lab,"%)",sep=""),sep=" ")

Note that in the current version of ggplot2, opts is deprecated, so we would use theme and element_blank now.

Python base64 data decode

Note Slipstream's response, that base64.b64encode and base64.b64decode need bytes-like object, not string.

>>> import base64
>>> a = '{"name": "John", "age": 42}'
>>> base64.b64encode(a)
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/usr/lib/python3.6/base64.py", line 58, in b64encode
    encoded = binascii.b2a_base64(s, newline=False)
TypeError: a bytes-like object is required, not 'str'

How do I sum values in a column that match a given condition using pandas?

The essential idea here is to select the data you want to sum, and then sum them. This selection of data can be done in several different ways, a few of which are shown below.

Boolean indexing

Arguably the most common way to select the values is to use Boolean indexing.

With this method, you find out where column 'a' is equal to 1 and then sum the corresponding rows of column 'b'. You can use loc to handle the indexing of rows and columns:

>>> df.loc[df['a'] == 1, 'b'].sum()
15

The Boolean indexing can be extended to other columns. For example if df also contained a column 'c' and we wanted to sum the rows in 'b' where 'a' was 1 and 'c' was 2, we'd write:

df.loc[(df['a'] == 1) & (df['c'] == 2), 'b'].sum()

Query

Another way to select the data is to use query to filter the rows you're interested in, select column 'b' and then sum:

>>> df.query("a == 1")['b'].sum()
15

Again, the method can be extended to make more complicated selections of the data:

df.query("a == 1 and c == 2")['b'].sum()

Note this is a little more concise than the Boolean indexing approach.

Groupby

The alternative approach is to use groupby to split the DataFrame into parts according to the value in column 'a'. You can then sum each part and pull out the value that the 1s added up to:

>>> df.groupby('a')['b'].sum()[1]
15

This approach is likely to be slower than using Boolean indexing, but it is useful if you want check the sums for other values in column a:

>>> df.groupby('a')['b'].sum()
a
1    15
2     8

Casting a number to a string in TypeScript

Use the "+" symbol to cast a string to a number.

window.location.hash = +page_number;

Logging levels - Logback - rule-of-thumb to assign log levels

I answer this coming from a component-based architecture, where an organisation may be running many components that may rely on each other. During a propagating failure, logging levels should help to identify both which components are affected and which are a root cause.

  • ERROR - This component has had a failure and the cause is believed to be internal (any internal, unhandled exception, failure of encapsulated dependency... e.g. database, REST example would be it has received a 4xx error from a dependency). Get me (maintainer of this component) out of bed.

  • WARN - This component has had a failure believed to be caused by a dependent component (REST example would be a 5xx status from a dependency). Get the maintainers of THAT component out of bed.

  • INFO - Anything else that we want to get to an operator. If you decide to log happy paths then I recommend limiting to 1 log message per significant operation (e.g. per incoming http request).

For all log messages be sure to log useful context (and prioritise on making messages human readable/useful rather than having reams of "error codes")

  • DEBUG (and below) - Shouldn't be used at all (and certainly not in production). In development I would advise using a combination of TDD and Debugging (where necessary) as opposed to polluting code with log statements. In production, the above INFO logging, combined with other metrics should be sufficient.

A nice way to visualise the above logging levels is to imagine a set of monitoring screens for each component. When all running well they are green, if a component logs a WARNING then it will go orange (amber) if anything logs an ERROR then it will go red.

In the event of an incident you should have one (root cause) component go red and all the affected components should go orange/amber.

How to remove td border with html?

To remove borders between cells, while retaining the border around the table, add the attribute rules=none to the table tag.

There is no way in HTML to achieve the rendering specified in the last figure of the question. There are various tricky workarounds that are based on using some other markup structure.

LaTeX "\indent" creating paragraph indentation / tabbing package requirement?

This is kind of a hack but the best solution that I have found is to use a description tag with no \item. This will produce an error from the latex compiler; however, the error does not prevent the pdf from being generated.

\begin{description} 
     <YOUR TEXT HERE> 
\end{description}
  • This only worked on windows latex compiler

How can I get (query string) parameters from the URL in Next.js?

For those looking for a solution that works with static exports, try the solution listed here: https://github.com/zeit/next.js/issues/4804#issuecomment-460754433

In a nutshell, router.query works only with SSR applications, but router.asPath still works.

So can either configure the query pre-export in next.config.js with exportPathMap (not dynamic):

    return {
      '/': { page: '/' },
      '/about': { page: '/about', query: { title: 'about-us' } }
    }
  }

Or use router.asPath and parse the query yourself with a library like query-string:

import { withRouter } from "next/router";
import queryString from "query-string";

export const withPageRouter = Component => {
  return withRouter(({ router, ...props }) => {
    router.query = queryString.parse(router.asPath.split(/\?/)[1]);

    return <Component {...props} router={router} />;
  });
};

Differences between time complexity and space complexity?

Time and Space complexity are different aspects of calculating the efficiency of an algorithm.

Time complexity deals with finding out how the computational time of an algorithm changes with the change in size of the input.

On the other hand, space complexity deals with finding out how much (extra)space would be required by the algorithm with change in the input size.

To calculate time complexity of the algorithm the best way is to check if we increase in the size of the input, will the number of comparison(or computational steps) also increase and to calculate space complexity the best bet is to see additional memory requirement of the algorithm also changes with the change in the size of the input.

A good example could be of Bubble sort.

Lets say you tried to sort an array of 5 elements. In the first pass you will compare 1st element with next 4 elements. In second pass you will compare 2nd element with next 3 elements and you will continue this procedure till you fully exhaust the list.

Now what will happen if you try to sort 10 elements. In this case you will start with comparing comparing 1st element with next 9 elements, then 2nd with next 8 elements and so on. In other words if you have N element array you will start of by comparing 1st element with N-1 elements, then 2nd element with N-2 elements and so on. This results in O(N^2) time complexity.

But what about size. When you sorted 5 element or 10 element array did you use any additional buffer or memory space. You might say Yes, I did use a temporary variable to make the swap. But did the number of variables changed when you increased the size of array from 5 to 10. No, Irrespective of what is the size of the input you will always use a single variable to do the swap. Well, this means that the size of the input has nothing to do with the additional space you will require resulting in O(1) or constant space complexity.

Now as an exercise for you, research about the time and space complexity of merge sort

How do I simulate a low bandwidth, high latency environment?

There is a product from http://www.shunra.com called VE Desktop which can be used to simulate varying network conditions. It allows you to tweak latencies, bandwidth and packetloss with a simple UI. Only caveat is, its not free. Hope this helps.

Writing String to Stream and reading it back does not work

Try this "one-liner" from Delta's Blog, String To MemoryStream (C#).

MemoryStream stringInMemoryStream =
   new MemoryStream(ASCIIEncoding.Default.GetBytes("Your string here"));

The string will be loaded into the MemoryStream, and you can read from it. See Encoding.GetBytes(...), which has also been implemented for a few other encodings.

Multi-gradient shapes

I don't think you can do this in XML (at least not in Android), but I've found a good solution posted here that looks like it'd be a great help!

ShapeDrawable.ShaderFactory sf = new ShapeDrawable.ShaderFactory() {
    @Override
    public Shader resize(int width, int height) {
        LinearGradient lg = new LinearGradient(0, 0, width, height,
            new int[]{Color.GREEN, Color.GREEN, Color.WHITE, Color.WHITE},
            new float[]{0,0.5f,.55f,1}, Shader.TileMode.REPEAT);
        return lg;
    }
};

PaintDrawable p=new PaintDrawable();
p.setShape(new RectShape());
p.setShaderFactory(sf);

Basically, the int array allows you to select multiple color stops, and the following float array defines where those stops are positioned (from 0 to 1). You can then, as stated, just use this as a standard Drawable.

Edit: Here's how you could use this in your scenario. Let's say you have a Button defined in XML like so:

<Button
    android:id="@+id/thebutton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Press Me!"
    />

You'd then put something like this in your onCreate() method:

Button theButton = (Button)findViewById(R.id.thebutton);
ShapeDrawable.ShaderFactory sf = new ShapeDrawable.ShaderFactory() {
    @Override
    public Shader resize(int width, int height) {
        LinearGradient lg = new LinearGradient(0, 0, 0, theButton.getHeight(),
            new int[] { 
                Color.LIGHT_GREEN, 
                Color.WHITE, 
                Color.MID_GREEN, 
                Color.DARK_GREEN }, //substitute the correct colors for these
            new float[] {
                0, 0.45f, 0.55f, 1 },
            Shader.TileMode.REPEAT);
         return lg;
    }
};
PaintDrawable p = new PaintDrawable();
p.setShape(new RectShape());
p.setShaderFactory(sf);
theButton.setBackground((Drawable)p);

I cannot test this at the moment, this is code from my head, but basically just replace, or add stops for the colors that you need. Basically, in my example, you would start with a light green, fade to white slightly before the center (to give a fade, rather than a harsh transition), fade from white to mid green between 45% and 55%, then fade from mid green to dark green from 55% to the end. This may not look exactly like your shape (Right now, I have no way of testing these colors), but you can modify this to replicate your example.

Edit: Also, the 0, 0, 0, theButton.getHeight() refers to the x0, y0, x1, y1 coordinates of the gradient. So basically, it starts at x = 0 (left side), y = 0 (top), and stretches to x = 0 (we're wanting a vertical gradient, so no left to right angle is necessary), y = the height of the button. So the gradient goes at a 90 degree angle from the top of the button to the bottom of the button.

Edit: Okay, so I have one more idea that works, haha. Right now it works in XML, but should be doable for shapes in Java as well. It's kind of complex, and I imagine there's a way to simplify it into a single shape, but this is what I've got for now:

green_horizontal_gradient.xml

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle"
    >
    <corners
        android:radius="3dp"
        />
    <gradient
        android:angle="0"
        android:startColor="#FF63a34a"
        android:endColor="#FF477b36"
        android:type="linear"
        />    
</shape>

half_overlay.xml

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle"
    >
    <solid
        android:color="#40000000"
        />
</shape>

layer_list.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list
    xmlns:android="http://schemas.android.com/apk/res/android"
    >
    <item
        android:drawable="@drawable/green_horizontal_gradient"
        android:id="@+id/green_gradient"
        />
    <item
        android:drawable="@drawable/half_overlay"
        android:id="@+id/half_overlay"
        android:top="50dp"
        />
</layer-list>

test.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center"
    >
    <TextView
        android:id="@+id/image_test"
        android:background="@drawable/layer_list"
        android:layout_width="fill_parent"
        android:layout_height="100dp"
        android:layout_marginLeft="15dp"
        android:layout_marginRight="15dp"
        android:gravity="center"
        android:text="Layer List Drawable!"
        android:textColor="@android:color/white"
        android:textStyle="bold"
        android:textSize="26sp"     
        />
</RelativeLayout>

Okay, so basically I've created a shape gradient in XML for the horizontal green gradient, set at a 0 degree angle, going from the top area's left green color, to the right green color. Next, I made a shape rectangle with a half transparent gray. I'm pretty sure that could be inlined into the layer-list XML, obviating this extra file, but I'm not sure how. But okay, then the kind of hacky part comes in on the layer_list XML file. I put the green gradient as the bottom layer, then put the half overlay as the second layer, offset from the top by 50dp. Obviously you'd want this number to always be half of whatever your view size is, though, and not a fixed 50dp. I don't think you can use percentages, though. From there, I just inserted a TextView into my test.xml layout, using the layer_list.xml file as my background. I set the height to 100dp (twice the size of the offset of the overlay), resulting in the following:

alt text

Tada!

One more edit: I've realized you can just embed the shapes into the layer list drawable as items, meaning you don't need 3 separate XML files any more! You can achieve the same result combining them like so:

layer_list.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list
    xmlns:android="http://schemas.android.com/apk/res/android"
    >
    <item>
        <shape
            xmlns:android="http://schemas.android.com/apk/res/android"
            android:shape="rectangle"
            >
            <corners
                android:radius="3dp"
                />
            <gradient
                android:angle="0"
                android:startColor="#FF63a34a"
                android:endColor="#FF477b36"
                android:type="linear"
                />    
        </shape>
    </item>
    <item
        android:top="50dp" 
        >
        <shape
            android:shape="rectangle"
            >
            <solid
                android:color="#40000000"
                />
        </shape>            
    </item>
</layer-list>

You can layer as many items as you like this way! I may try to play around and see if I can get a more versatile result through Java.

I think this is the last edit...: Okay, so you can definitely fix the positioning through Java, like the following:

    TextView tv = (TextView)findViewById(R.id.image_test);
    LayerDrawable ld = (LayerDrawable)tv.getBackground();
    int topInset = tv.getHeight() / 2 ; //does not work!
    ld.setLayerInset(1, 0, topInset, 0, 0);
    tv.setBackgroundDrawable(ld);

However! This leads to yet another annoying problem in that you cannot measure the TextView until after it has been drawn. I'm not quite sure yet how you can accomplish this...but manually inserting a number for topInset does work.

I lied, one more edit

Okay, found out how to manually update this layer drawable to match the height of the container, full description can be found here. This code should go in your onCreate() method:

final TextView tv = (TextView)findViewById(R.id.image_test);
        ViewTreeObserver vto = tv.getViewTreeObserver();
        vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                LayerDrawable ld = (LayerDrawable)tv.getBackground();
                ld.setLayerInset(1, 0, tv.getHeight() / 2, 0, 0);
            }
        });

And I'm done! Whew! :)

How do I remove an array item in TypeScript?

One more solution using Typescript:

let updatedArray = [];
for (let el of this.oldArray) {
    if (el !== elementToRemove) {
        updated.push(el);
    }
}
this.oldArray = updated;

How do I create a shortcut via command-line in Windows?

I created a VB script and run it either from command line or from a Java process. I also tried to catch errors when creating the shortcut so I can have a better error handling.

Set oWS = WScript.CreateObject("WScript.Shell")
shortcutLocation = Wscript.Arguments(0)

'error handle shortcut creation
On Error Resume Next
Set oLink = oWS.CreateShortcut(shortcutLocation)
If Err Then WScript.Quit Err.Number

'error handle setting shortcut target
On Error Resume Next
oLink.TargetPath = Wscript.Arguments(1)
If Err Then WScript.Quit Err.Number

'error handle setting start in property
On Error Resume Next
oLink.WorkingDirectory = Wscript.Arguments(2)
If Err Then WScript.Quit Err.Number

'error handle saving shortcut
On Error Resume Next
oLink.Save
If Err Then WScript.Quit Err.Number

I run the script with the following commmand:

cscript /b script.vbs shortcutFuturePath targetPath startInProperty

It is possible to have it working even without setting the 'Start in' property in some cases.

How to list all the available keyspaces in Cassandra?

  1. login to cqlsh

  2. use below command to get names/list of keyspaces present

         SELECT keyspace_name FROM system_schema.keyspaces;
    

Recyclerview and handling different type of row inflation

You can use the library: https://github.com/vivchar/RendererRecyclerViewAdapter

mRecyclerViewAdapter = new RendererRecyclerViewAdapter(); /* included from library */
mRecyclerViewAdapter.registerRenderer(new SomeViewRenderer(SomeModel.TYPE, this));
mRecyclerViewAdapter.registerRenderer(...); /* you can use several types of cells */

For each item, you should to implement a ViewRenderer, ViewHolder, SomeModel:

ViewHolder - it is a simple view holder of recycler view.

SomeModel - it is your model with ItemModel interface

public class SomeViewRenderer extends ViewRenderer<SomeModel, SomeViewHolder> {

    public SomeViewRenderer(final int type, final Context context) {
        super(type, context);
    }

    @Override
    public void bindView(@NonNull final SomeModel model, @NonNull final SomeViewHolder holder) {
       holder.mTitle.setText(model.getTitle());
    }

    @NonNull
    @Override
    public SomeViewHolder createViewHolder(@Nullable final ViewGroup parent) {
        return new SomeViewHolder(LayoutInflater.from(getContext()).inflate(R.layout.some_item, parent, false));
    }
}

For more details you can look documentations.

how do you insert null values into sql server

If you're using SSMS (or old school Enterprise Manager) to edit the table directly, press CTRL+0 to add a null.

Adding values to Arraylist

Actually, a third is preferred:

ArrayList<Object> array = new ArrayList<Object>();
array.add(Integer.valueOf(3));
array.add("ss");

This avoids autoboxing (Integer.valueOf(3) versus 3) and doesn't create an unnecessary String object.

Eclipse complains when you don't use type arguments with a generic type like ArrayList, because you are using something called a raw type, which is discouraged. If a class is generic (that is, it has type parameters), then you should always use type arguments with that class.

Autoboxing, on the other hand, is a personal preference. Some people are okay with it, and some not. I don't like it, and I turn on the warning for autoboxing/autounboxing.

How to create a cron job using Bash automatically without the interactive editor?

My preferred solution to this would be this:

(crontab -l | grep . ; echo -e "0 4 * * * myscript\n") | crontab -

This will make sure you are handling the blank new line at the bottom correctly. To avoid issues with crontab you should usually end the crontab file with a blank new line. And the script above makes sure it first removes any blank lines with the "grep ." part, and then add in a new blank line at the end with the "\n" in the end of the script. This will also prevent getting a blank line above your new command if your existing crontab file ends with a blank line.

Nexus 7 (2013) and Win 7 64 - cannot install USB driver despite checking many forums and online resources

The universal adb driver installer worked for me. I went from an HTC to a Samsung to a LG Nexus. The drivers are all over the place for me.

http://adbdriver.com/

Best way to do Version Control for MS Excel

Use any of the standard version control tools like SVN or CVS. Limitations would depend on whats the objective. Apart from a small increase in size of the repository, i did'nt face any issues

SQL Server - Create a copy of a database table and place it in the same database?

You need to write SSIS to copy the table and its data, constraints and triggers. We have in our organization a software called Kal Admin by kalrom Systems that has a free version for downloading (I think that the copy tables feature is optional)

Masking password input from the console : Java

You would use the Console class

char[] password = console.readPassword("Enter password");  
Arrays.fill(password, ' ');

By executing readPassword echoing is disabled. Also after the password is validated it is best to overwrite any values in the array.

If you run this from an ide it will fail, please see this explanation for a thorough answer: Explained

How to remove default mouse-over effect on WPF buttons?

Just to add a very simple solution, that was good enough for me, and I think addresses the OP's issue. I used the solution in this answer except with a regular Background value instead of an image.

<Style x:Key="SomeButtonStyle" TargetType="Button">
    <Setter Property="Background" Value="Transparent" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="Button">
                <Grid Background="{TemplateBinding Background}">
                    <ContentPresenter />
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

No re-templating beyond forcing the Background to always be the Transparent background from the templated button - mouseover no longer affects the background once this is done. Obviously replace Transparent with any preferred value.

Reading rather large json files in Python

The issue here is that JSON, as a format, is generally parsed in full and then handled in-memory, which for such a large amount of data is clearly problematic.

The solution to this is to work with the data as a stream - reading part of the file, working with it, and then repeating.

The best option appears to be using something like ijson - a module that will work with JSON as a stream, rather than as a block file.

Edit: Also worth a look - kashif's comment about json-streamer and Henrik Heino's comment about bigjson.

Remove all occurrences of a value from a list?

At the cost of readability, I think this version is slightly faster as it doesn't force the while to reexamine the list, thus doing exactly the same work remove has to do anyway:

x = [1, 2, 3, 4, 2, 2, 3]
def remove_values_from_list(the_list, val):
    for i in range(the_list.count(val)):
        the_list.remove(val)

remove_values_from_list(x, 2)

print(x)

WPF Datagrid Get Selected Cell Value

you can also use this function.

 public static void GetGridSelectedView(out string tuid, ref DataGrid dataGrid,string Column)
    {
        try
        {
            // grid selected row values
            var item = dataGrid.SelectedItem as DataRowView;
            if (null == item) tuid = null;
            if (item.DataView.Count > 0)
            {
                tuid =  item.DataView[dataGrid.SelectedIndex][Column].ToString().Trim();
            }
            else { tuid = null; }
        }
        catch (Exception exc) { System.Windows.MessageBox.Show(exc.Message); tuid = null; }
    }

What is apache's maximum url length?

Allowed default size of URI is 8177 characters in GET request. Simple code in python for such testing.

#!/usr/bin/env python2

import sys
import socket

if __name__ == "__main__":
    string = sys.argv[1]
    buf_get = "x" * int(string)
    buf_size = 1024
    request = "HEAD %s HTTP/1.1\nHost:localhost\n\n" % buf_get
    print "===>", request

    sock_http = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock_http.connect(("localhost", 80))
    sock_http.send(request)
    while True:
       print "==>", sock_http.recv(buf_size)
       if not sock_http.recv(buf_size):
           break
    sock_http.close()

On 8178 characters you will get such message: HTTP/1.1 414 Request-URI Too Large

How do I URL encode a string

Swift 2.0 Example (iOS 9 Compatiable)

extension String {

  func stringByURLEncoding() -> String? {

    let characters = NSCharacterSet.URLQueryAllowedCharacterSet().mutableCopy() as! NSMutableCharacterSet

    characters.removeCharactersInString("&")

    guard let encodedString = self.stringByAddingPercentEncodingWithAllowedCharacters(characters) else {
      return nil
    }

    return encodedString

  }

}

sum two columns in R

You can do this :

    df <- data.frame("a" = c(1,2,3,4), "b" = c(4,3,2,1), "x_ind" = c(1,0,1,1), "y_ind" = c(0,0,1,1), "z_ind" = c(0,1,1,1) )
df %>% mutate( bi  = ifelse((df$x_ind + df$y_ind +df$z_ind)== 3, 1,0 ))

Handling multiple IDs in jQuery

Solution:

To your secondary question

var elem1 = $('#elem1'),
    elem2 = $('#elem2'),
    elem3 = $('#elem3');

You can use the variable as the replacement of selector.

elem1.css({'display':'none'}); //will work

In the below case selector is already stored in a variable.

$(elem1,elem2,elem3).css({'display':'none'}); // will not work

How to install ia32-libs in Ubuntu 14.04 LTS (Trusty Tahr)

The best answer I have ever seen is How to run 32-bit applications on Ubuntu 64-bit?

sudo dpkg --add-architecture i386
sudo apt-get update
sudo apt-get install libc6:i386 libncurses5:i386 libstdc++6:i386
sudo ./adb

How to write an async method with out parameter?

You can do this by using TPL (task parallel library) instead of direct using await keyword.

private bool CheckInCategory(int? id, out Category category)
    {
        if (id == null || id == 0)
            category = null;
        else
            category = Task.Run(async () => await _context.Categories.FindAsync(id ?? 0)).Result;

        return category != null;
    }

if(!CheckInCategory(int? id, out var category)) return error

Rounding to two decimal places in Python 2.7?

print "financial return of outcome 1 = $%.2f" % (out1)

Loading context in Spring using web.xml

You can also specify context location relatively to current classpath, which may be preferable

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:applicationContext*.xml</param-value>
</context-param>

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

How do I auto-resize an image to fit a 'div' container?

A simple solution (4-step fix!!) that seems to work for me, is below. The example uses the width to determine the overall size, but you can also flip it to use the height instead.

  1. Apply CSS styling to the image container (for example, <img>)
  2. Set the width property to the dimension you want
    • For dimensions, use % for relative size, or autoscaling (based on image container or display)
    • Use px (or other) for a static, or set dimension
  3. Set the height property to automatically adjust, based on the width
  4. ENJOY!

For example,

<img style="width:100%; height:auto;"
    src="https://googledrive.com/host/0BwDx0R31u6sYY1hPWnZrencxb1k/thanksgiving.png"
/>

Recursive query in SQL Server

Try this:

;WITH CTE
AS
(
    SELECT DISTINCT
        M1.Product_ID Group_ID,
        M1.Product_ID
    FROM matches M1
        LEFT JOIN matches M2
            ON M1.Product_Id = M2.matching_Product_Id
    WHERE M2.matching_Product_Id IS NULL
    UNION ALL
    SELECT
        C.Group_ID,
        M.matching_Product_Id
    FROM CTE C
        JOIN matches M
            ON C.Product_ID = M.Product_ID
)
SELECT * FROM CTE ORDER BY Group_ID

You can use OPTION(MAXRECURSION n) to control recursion depth.

SQL FIDDLE DEMO

React: "this" is undefined inside a component function

You should notice that this depends on how function is invoked ie: when a function is called as a method of an object, its this is set to the object the method is called on.

this is accessible in JSX context as your component object, so you can call your desired method inline as this method.

If you just pass reference to function/method, it seems that react will invoke it as independent function.

onClick={this.onToggleLoop} // Here you just passing reference, React will invoke it as independent function and this will be undefined

onClick={()=>this.onToggleLoop()} // Here you invoking your desired function as method of this, and this in that function will be set to object from that function is called ie: your component object

Error: No module named psycopg2.extensions

This error raise because you not install postgres database in you project virtutal environment. you should run one of these command. from a terminal you can you command for sudo.

sudo apt-get install build-dep python-psycopg2

for pip (pip basically work for python)

pip install psycopg2

or

pip3 install psycopg2-binary

i'm pretty sure it will work for you.

What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function?

FYI, in case you need to add attributes to your dictionary (things that are attached to the dictionary, but are not one of the keys), then you'll need the second form. In that case, you can initialize your dictionary with keys having arbitrary characters, one at a time, like so:

    class mydict(dict): pass
    a = mydict()        
    a["b=c"] = 'value'
    a.test = False

ConcurrentModificationException for ArrayList

You can't remove from list if you're browsing it with "for each" loop. You can use Iterator. Replace:

for (DrugStrength aDrugStrength : aDrugStrengthList) {
    if (!aDrugStrength.isValidDrugDescription()) {
        aDrugStrengthList.remove(aDrugStrength);
    }
}

With:

for (Iterator<DrugStrength> it = aDrugStrengthList.iterator(); it.hasNext(); ) {
    DrugStrength aDrugStrength = it.next();
    if (!aDrugStrength.isValidDrugDescription()) {
        it.remove();
    }
}

What is the difference between UTF-8 and ISO-8859-1?

  • ASCII: 7 bits. 128 code points.

  • ISO-8859-1: 8 bits. 256 code points.

  • UTF-8: 8-32 bits (1-4 bytes). 1,112,064 code points.

Both ISO-8859-1 and UTF-8 are backwards compatible with ASCII, but UTF-8 is not backwards compatible with ISO-8859-1:

#!/usr/bin/env python3

c = chr(0xa9)
print(c)
print(c.encode('utf-8'))
print(c.encode('iso-8859-1'))

Output:

©
b'\xc2\xa9'
b'\xa9'

How to invoke function from external .c file in C?

There are many great contributions here, but let me add mine non the less.

First thing i noticed is, you did not make any promises in the main file that you were going to create a function known as add(). This count have been done like this in the main file:

    int add(int a, int b); 

before your main function, that way your main function would recognize the add function and try to look for its executable code. So essentially your files should be

Main.c

    int add(int a, int b);

    int main(void) {
        int result = add(5,6);
        printf("%d\n", result);
    }  

and // add.c

    int add(int a, int b) {
        return a + b;
    }

Change working directory in my current shell context when running Node script

The correct way to change directories is actually with process.chdir(directory). Here's an example from the documentation:

console.log('Starting directory: ' + process.cwd());
try {
  process.chdir('/tmp');
  console.log('New directory: ' + process.cwd());
}
catch (err) {
  console.log('chdir: ' + err);
}

This is also testable in the Node.js REPL:

[monitor@s2 ~]$ node
> process.cwd()
'/home/monitor'
> process.chdir('../');
undefined
> process.cwd();
'/home'

How to get response as String using retrofit without using GSON or any other library in android

** Update ** A scalars converter has been added to retrofit that allows for a String response with less ceremony than my original answer below.

Example interface --

public interface GitHubService {
    @GET("/users/{user}")
    Call<String> listRepos(@Path("user") String user);
}

Add the ScalarsConverterFactory to your retrofit builder. Note: If using ScalarsConverterFactory and another factory, add the scalars factory first.

Retrofit retrofit = new Retrofit.Builder()
    .baseUrl(BASE_URL)
    .addConverterFactory(ScalarsConverterFactory.create())
    // add other factories here, if needed.
    .build();

You will also need to include the scalars converter in your gradle file --

implementation 'com.squareup.retrofit2:converter-scalars:2.1.0'

--- Original Answer (still works, just more code) ---

I agree with @CommonsWare that it seems a bit odd that you want to intercept the request to process the JSON yourself. Most of the time the POJO has all the data you need, so no need to mess around in JSONObject land. I suspect your specific problem might be better solved using a custom gson TypeAdapter or a retrofit Converter if you need to manipulate the JSON. However, retrofit provides more the just JSON parsing via Gson. It also manages a lot of the other tedious tasks involved in REST requests. Just because you don't want to use one of the features, doesn't mean you have to throw the whole thing out. There are times you just want to get the raw stream, so here is how to do it -

First, if you are using Retrofit 2, you should start using the Call API. Instead of sending an object to convert as the type parameter, use ResponseBody from okhttp --

public interface GitHubService {
    @GET("/users/{user}")
    Call<ResponseBody> listRepos(@Path("user") String user);
}

then you can create and execute your call --

GitHubService service = retrofit.create(GitHubService.class);
Call<ResponseBody> result = service.listRepos(username);
result.enqueue(new Callback<ResponseBody>() {
    @Override
    public void onResponse(Response<ResponseBody> response) {
        try {
            System.out.println(response.body().string());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onFailure(Throwable t) {
        e.printStackTrace();
    }
});

Note The code above calls string() on the response object, which reads the entire response into a String. If you are passing the body off to something that can ingest streams, you can call charStream() instead. See the ResponseBody docs.

Convert an integer to a float number

There is no float type. Looks like you want float64. You could also use float32 if you only need a single-precision floating point value.

package main

import "fmt"

func main() {
    i := 5
    f := float64(i)
    fmt.Printf("f is %f\n", f)
}

How to style dt and dd so they are on the same line?

I need to do this and have the <dt> content vertically centered, relative to the <dd> content. I used display: inline-block, together with vertical-align: middle

See full example on Codepen here

.dl-horizontal {
  font-size: 0;
  text-align: center;

  dt, dd {
    font-size: 16px;
    display: inline-block;
    vertical-align: middle;
    width: calc(50% - 10px);
  }

  dt {
    text-align: right;
    padding-right: 10px;
  }

  dd {
    font-size: 18px;
    text-align: left;
    padding-left: 10px;
  } 
}

How do I detect the Python version at runtime?

Try this code, this should work:

import platform
print(platform.python_version())

What are the differences between JSON and JSONP?

JSONP is a simple way to overcome browser restrictions when sending JSON responses from different domains from the client.

But the practical implementation of the approach involves subtle differences that are often not explained clearly.

Here is a simple tutorial that shows JSON and JSONP side by side.

All the code is freely available at Github and a live version can be found at http://json-jsonp-tutorial.craic.com

php - get numeric index of associative array


  $a = array(
      'blue' => 'nice',
      'car' => 'fast',
      'number' => 'none'
  );  
var_dump(array_search('car', array_keys($a)));
var_dump(array_search('blue', array_keys($a)));
var_dump(array_search('number', array_keys($a)));

What does the error "arguments imply differing number of rows: x, y" mean?

Your data.frame mat is rectangular (n_rows!= n_cols).

Therefore, you cannot make a data.frame out of the column- and rownames, because each column in a data.frame must be the same length.

Maybe this suffices your needs:

require(reshape2)
mat$id <- rownames(mat) 
melt(mat)

C/C++ include header file order

To add my own brick to the wall.

  1. Each header needs to be self-sufficient, which can only be tested if it's included first at least once
  2. One should not mistakenly modify the meaning of a third-party header by introducing symbols (macro, types, etc.)

So I usually go like this:

// myproject/src/example.cpp
#include "myproject/example.h"

#include <algorithm>
#include <set>
#include <vector>

#include <3rdparty/foo.h>
#include <3rdparty/bar.h>

#include "myproject/another.h"
#include "myproject/specific/bla.h"

#include "detail/impl.h"

Each group separated by a blank line from the next one:

  • Header corresponding to this cpp file first (sanity check)
  • System headers
  • Third-party headers, organized by dependency order
  • Project headers
  • Project private headers

Also note that, apart from system headers, each file is in a folder with the name of its namespace, just because it's easier to track them down this way.

Docker Error bind: address already in use

Before it was running on :docker run -d --name oracle -p 1521:1521 -p 5500:5500 qa/oracle I just changed the port to docker run -d --name oracle -p 1522:1522 -p 5500:5500 qa/oracle

it worked fine for me !

Python loop for inside lambda

anon and chepner's answers are on the right track. Python 3.x has a print function and this is what you will need if you want to embed print within a function (and, a fortiori, lambdas).

However, you can get the print function very easily in python 2.x by importing from the standard library's future module. Check it out:

>>>from __future__ import print_function
>>>
>>>iterable = ["a","b","c"]
>>>map(print, iterable)
a
b
c
[None, None, None]
>>>

I guess that looks kind of weird, so feel free to assign the return to _ if you would like to suppress [None, None, None]'s output (you are interested in the side-effects only, I assume):

>>>_ = map(print, iterable)
a
b
c
>>>

How to get response body using HttpURLConnection, when code other than 2xx is returned?

Wrong method was used for errors, here is the working code:

BufferedReader br = null;
if (100 <= conn.getResponseCode() && conn.getResponseCode() <= 399) {
    br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
} else {
    br = new BufferedReader(new InputStreamReader(conn.getErrorStream()));
}

Initializing select with AngularJS and ng-repeat

The fact that angular is injecting an empty option element to the select is that the model object binded to it by default comes with an empty value in when initialized.

If you want to select a default option then you can probably can set it on the scope in the controller

$scope.filterCondition.operator = "your value here";

If you want to an empty option placeholder, this works for me

<select ng-model="filterCondition.operator" ng-options="operator.id as operator.name for operator in operators">
  <option value="">Choose Operator</option>
</select>

Move view with keyboard using Swift

For Black Screen Error ( Swift 4 & 4.2 ) .

I fixed the black screen problem. In the verified solution The keyboard height changes after tapping and this is causing black screen.

Have to use UIKeyboardFrameEndUserInfoKey instead of UIKeyboardFrameBeginUserInfoKey

var isKeyboardAppear = false

override func viewDidLoad() {
    super.viewDidLoad() 
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

@objc func keyboardWillShow(notification: NSNotification) {
    if !isKeyboardAppear {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            if self.view.frame.origin.y == 0{
                self.view.frame.origin.y -= keyboardSize.height
            }
        }
        isKeyboardAppear = true
    }
}

@objc func keyboardWillHide(notification: NSNotification) {
    if isKeyboardAppear {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            if self.view.frame.origin.y != 0{
                self.view.frame.origin.y += keyboardSize.height
            }
        }
         isKeyboardAppear = false
    }
}

android button selector

In Layout .xml file

<Button
 android:id="@+id/button1"
 android:background="@drawable/btn_selector"
 android:layout_width="100dp"
 android:layout_height="50dp"
 android:text="press" />

btn_selector.xml

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

 <item android:drawable="@drawable/btn_bg_selected" android:state_selected="true"></item>
<item android:drawable="@drawable/btn_bg_pressed" android:state_pressed="true"></item>
<item android:drawable="@drawable/btn_bg_normal"></item>

Is CSS Turing complete?

This answer is not accurate because it mix description of UTM and UTM itself (Universal Turing Machine).

We have good answer but from different perspective and it do not show directly flaws in current top answer.


First of all we can agree that human can work as UTM. This mean if we do

CSS + Human == UTM

Then CSS part is useless because all work can be done by Human who will do UTM part. Act of clicking can be UTM, because you do not click at random but only in specific places.

Instead of CSS I could use this text (Rule 110):

000 -> 0
001 -> 1
010 -> 1
011 -> 1
100 -> 0
101 -> 1
110 -> 1
111 -> 0

To guide my actions and result will be same. This mean this text UTM? No this is only input (description) that other UTM (human or computer) can read and run. Clicking is enough to run any UTM.


Critical part that CSS lack is ability to change of it own state in arbitrary way, if CSS could generate clicks then it would be UTM. Argument that your clicks are "crank" for CSS is not accurate because real "crank" for CSS is Layout Engine that run it and it should be enough to prove that CSS is UTM.

mysql datatype for telephone number and address

INT(10) does not mean a 10-digit number, it means an integer with a display width of 10 digits. The maximum value for an INT in MySQL is 2147483647 (or 4294967295 if unsigned).

You can use a BIGINT instead of INT to store it as a numeric. Using BIGINT will save you 3 bytes per row over VARCHAR(10).

To Store "Country + area + number separately". You can try using a VARCHAR(20), this allows you the ability to store international phone numbers properly, should that need arise.

android.app.Application cannot be cast to android.app.Activity

You can also try this one.

override fun registerWith( registry: PluginRegistry) {
        GeneratedPluginRegistrant.registerWith(registry as FlutterEngine)       
    //registry.registrarFor("io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin")
    }

I think this one is far better solution than creating a new class.

Converting bytes to megabytes

In general, it's wrong to use decimal SI prefixes (e.g. kilo, mega) when referring to binary data sizes (except in casual usage). It's ambiguous and causes confusion. To be precise you can use binary prefixes (e.g. 1 mebibyte = 1 MiB = 1024 kibibytes = 2^20 bytes). When someone else uses decimal SI prefixes for binary data you need to get more information before you can know what is meant.

How can I get list of values from dict?

You can use * operator to unpack dict_values:

>>> d = {1: "a", 2: "b"}
>>> [*d.values()]
['a', 'b']

or list object

>>> d = {1: "a", 2: "b"}
>>> list(d.values())
['a', 'b']

How to fix 'Object arrays cannot be loaded when allow_pickle=False' for imdb.load_data() function?

This error comes when you have the previous version of torch like 1.6.0 with torchvision==0.7.0, you may check yours torch version through this command:

import tensorflow
print(tensorflow.__version__)

this error is already resolved in the newer version of torch.

you can remove this error through making the following change in np.load()

np.load(somepath, allow_pickle=True)

The allow_pickle=True will solve it

Aggregate / summarize multiple variables per group (e.g. sum, mean)

Yes, in your formula, you can cbind the numeric variables to be aggregated:

aggregate(cbind(x1, x2) ~ year + month, data = df1, sum, na.rm = TRUE)
   year month         x1          x2
1  2000     1   7.862002   -7.469298
2  2001     1 276.758209  474.384252
3  2000     2  13.122369 -128.122613
...
23 2000    12  63.436507  449.794454
24 2001    12 999.472226  922.726589

See ?aggregate, the formula argument and the examples.

Transferring files over SSH

If copying to/from your desktop machine, use WinSCP, or if on Linux, Nautilus supports SCP via the Connect To Server option.

scp can only copy files to a machine running sshd, hence you need to run the client software on the remote machine from the one you are running scp on.

If copying on the command line, use:

# copy from local machine to remote machine
scp localfile user@host:/path/to/whereyouwant/thefile

or

# copy from remote machine to local machine
scp user@host:/path/to/remotefile localfile

Extracting text OpenCV

You can utilize a python implementation SWTloc.

Full Disclosure : I am the author of this library

To do that :-

First and Second Image

Notice that the text_mode here is 'lb_df', which stands for Light Background Dark Foreground i.e the text in this image is going to be in darker color than the background

from swtloc import SWTLocalizer
from swtloc.utils import imgshowN, imgshow

swtl = SWTLocalizer()
# Stroke Width Transform
swtl.swttransform(imgpaths='img1.jpg', text_mode = 'lb_df',
                  save_results=True, save_rootpath = 'swtres/',
                  minrsw = 3, maxrsw = 20, max_angledev = np.pi/3)
imgshow(swtl.swtlabelled_pruned13C)

# Grouping
respacket=swtl.get_grouped(lookup_radii_multiplier=0.9, ht_ratio=3.0)
grouped_annot_bubble = respacket[2]
maskviz = respacket[4]
maskcomb  = respacket[5]

# Saving the results
_=cv2.imwrite('img1_processed.jpg', swtl.swtlabelled_pruned13C)
imgshowN([maskcomb, grouped_annot_bubble], savepath='grouped_img1.jpg')

enter image description here enter image description here


enter image description here enter image description here

Third Image

Notice that the text_mode here is 'db_lf', which stands for Dark Background Light Foreground i.e the text in this image is going to be in lighter color than the background

from swtloc import SWTLocalizer
from swtloc.utils import imgshowN, imgshow

swtl = SWTLocalizer()
# Stroke Width Transform
swtl.swttransform(imgpaths=imgpaths[1], text_mode = 'db_lf',
              save_results=True, save_rootpath = 'swtres/',
              minrsw = 3, maxrsw = 20, max_angledev = np.pi/3)
imgshow(swtl.swtlabelled_pruned13C)

# Grouping
respacket=swtl.get_grouped(lookup_radii_multiplier=0.9, ht_ratio=3.0)
grouped_annot_bubble = respacket[2]
maskviz = respacket[4]
maskcomb  = respacket[5]

# Saving the results
_=cv2.imwrite('img1_processed.jpg', swtl.swtlabelled_pruned13C)
imgshowN([maskcomb, grouped_annot_bubble], savepath='grouped_img1.jpg')

enter image description here enter image description here

You will also notice that the grouping done is not so accurate, to get the desired results as the images might vary, try to tune the grouping parameters in swtl.get_grouped() function.

How to fix 'sudo: no tty present and no askpass program specified' error?

Using pipeline:

echo your_pswd | sudo -S your_cmd

Using here-document:

sudo -S cmd <<eof
pwd
eof
#remember to put the above two lines without "any" indentations.

Open a terminal to ask password (whichever works):

gnome-terminal -e "sudo cmd"
xterm -e "sudo cmd"

How to comment/uncomment in HTML code

My view templates are generally .php files. This is what I would be using for now.

<?php // Some comment here ?>

The solution is quite similar to what @Robert suggested, works for me. Is not very clean I guess.

python: iterate a specific range in a list

By using iter builtin:

l = [1, 2, 3]
# i is the first item.
i = iter(l)
next(i)
for d in i:
    print(d)

Mockito, JUnit and Spring

Here's my short summary.

If you want to write a unit test, don't use a Spring applicationContext because you don't want any real dependencies injected in the class you are unit testing. Instead use mocks, either with the @RunWith(MockitoJUnitRunner.class) annotation on top of the class, or with MockitoAnnotations.initMocks(this) in the @Before method.

If you want to write an integration test, use:

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("yourTestApplicationContext.xml")

To set up your application context with an in-memory database for example. Normally you don't use mocks in integration tests, but you could do it by using the MockitoAnnotations.initMocks(this) approach described above.

Reduce left and right margins in matplotlib plot

The problem with matplotlibs subplots_adjust is that the values you enter are relative to the x and y figsize of the figure. This example is for correct figuresizing for printing of a pdf:

For that, I recalculate the relative spacing to absolute values like this:

pyplot.subplots_adjust(left = (5/25.4)/figure.xsize, bottom = (4/25.4)/figure.ysize, right = 1 - (1/25.4)/figure.xsize, top = 1 - (3/25.4)/figure.ysize)

for a figure of 'figure.xsize' inches in x-dimension and 'figure.ysize' inches in y-dimension. So the whole figure has a left margin of 5 mm, bottom margin of 4 mm, right of 1 mm and top of 3 mm within the labels are placed. The conversion of (x/25.4) is done because I needed to convert mm to inches.

Note that the pure chart size of x will be "figure.xsize - left margin - right margin" and the pure chart size of y will be "figure.ysize - bottom margin - top margin" in inches

Other sniplets (not sure about these ones, I just wanted to provide the other parameters)

pyplot.figure(figsize = figureSize, dpi = None)

and

pyplot.savefig("outputname.eps", dpi = 100)

How do I write out a text file in C# with a code page other than UTF-8?

You can have something like this

 switch (EncodingFormat.Trim().ToLower())
    {
        case "utf-8":
            File.WriteAllBytes(fileName, ASCIIEncoding.Convert(ASCIIEncoding.ASCII, new UTF8Encoding(false), convertToCSV(result, fileName)));
            break;
        case "utf-8+bom":
            File.WriteAllBytes(fileName, ASCIIEncoding.Convert(ASCIIEncoding.ASCII, new UTF8Encoding(true), convertToCSV(result, fileName)));
            break;
        case "ISO-8859-1":
            File.WriteAllBytes(fileName, ASCIIEncoding.Convert(ASCIIEncoding.ASCII, Encoding.GetEncoding("iso-8859-1"), convertToCSV(result, fileName)));
            break;
        case ..............
    }

Are multiple `.gitignore`s frowned on?

There are many scenarios where you want to commit a directory to your Git repo but without the files in it, for example the logs, cache, uploads directories etc.

So what I always do is to add a .gitignore file in those directories with the following content:

*
!.gitignore

With this .gitignore file, Git will not track any files in those directories yet still allow me to add the .gitignore file and hence the directory itself to the repo.

Regular expression for matching latitude/longitude coordinates?

Actually Alix Axel, above regex is wrong in latitude, longitude ranges point of view.

Latitude measurements range from –90° to +90° Longitude measurements range from –180° to +180°

So the regex given below validates more accurately.
Also, as per my thought no one should restrict decimal point in latitude/longitude.

^([-+]?\d{1,2}([.]\d+)?),\s*([-+]?\d{1,3}([.]\d+)?)$

OR for Objective C

^([-+]?\\d{1,2}([.]\\d+)?),\\s*([-+]?\\d{1,3}([.]\\d+)?)$

How do I properly force a Git push?

If I'm on my local branch A, and I want to force push local branch B to the origin branch C I can use the following syntax:

git push --force origin B:C

ListView with Add and Delete Buttons in each Row in android

on delete button click event

public void delete(View v){                

    ListView listview1;
    ArrayList<E> datalist;

    final int position = listview1.getPositionForView((View) v.getParent());
    datalist.remove(position);
    myAdapter.notifyDataSetChanged();

}

Spring Boot how to hide passwords in properties file

Spring Cloud Config Server will allow this type of behavior. Using JCE you can setup a key on the server and use it to cipher the apps properties.

http://cloud.spring.io/spring-cloud-config/spring-cloud-config.html

How to hide iOS status bar

Try that;

[[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationNone];

Python and pip, list all versions of a package that's available?

https://pypi.python.org/pypi/Django/ - works for packages whose maintainers choose to show all packages https://pypi.python.org/simple/pip/ - should do the trick anyhow (lists all links)

How to input a path with a white space?

You can escape the "space" char by putting a \ right before it.

reading a line from ifstream into a string variable

Use the std::getline() from <string>.

 istream & getline(istream & is,std::string& str)

So, for your case it would be:

std::getline(read,x);

"Cannot update paths and switch to branch at the same time"

'origin/master' which can not be resolved as commit

Strange: you need to check your remotes:

git remote -v

And make sure origin is fetched:

git fetch origin

Then:

git branch -avv

(to see if you do have fetched an origin/master branch)

Finally, use git switch instead of the confusing git checkout, with Git 2.23+ (August 2019).

git switch -c test --track origin/master

React.js inline style best practices

I prefer to use styled-components. It provide better solution for design.

import React, { Component, Fragment } from 'react'
import styled from 'styled-components';

const StyledDiv = styled.div`
    display: block;
    margin-left: auto;
    margin-right: auto;
    font-size:200; // here we can set static
    color: ${props => props.color} // set dynamic color by props
`;

export default class RenderHtml extends Component {
    render() {
        return (
            <Fragment>
                <StyledDiv color={'white'}>
                    Have a good and productive day!
                </StyledDiv>
            </Fragment>
        )
    }
}

Format date in a specific timezone

I was having the same issue with Moment.js. I've installed moment-timezone, but the issue wasn't resolved. Then, I did just what here it's exposed, set the timezone and it works like a charm:

moment(new Date({your_date})).zone("+08:00")

Thanks a lot!

How to handle authentication popup with Selenium WebDriver using Java

If you have to deal with NTLM proxy authentication a good alternative is to use a configure a local proxy using CNTLM.

The credentials and domain are configured in /etc/cntlm.conf.

Afterwards you can just use you own proxy that handles all the NTLM stuff.

DesiredCapabilities capabilities = DesiredCapabilities.chrome();

Proxy proxy = new Proxy();
proxy.setHttpProxy("localhost:3128");
capabilities.setCapability(CapabilityType.PROXY, proxy);

driver = new ChromeDriver(capabilities);

Pass multiple values with onClick in HTML link

A few things here...

If you want to call a function when the onclick event happens, you'll just want the function name plus the parameters.

Then if your parameters are a variable (which they look like they are), then you won't want quotes around them. Not only that, but if these are global variables, you'll want to add in "window." before that, because that's the object that holds all global variables.

Lastly, if these parameters aren't variables, you'll want to exclude the slashes to escape those characters. Since the value of onclick is wrapped by double quotes, single quotes won't be an issue. So your answer will look like this...

<a href=# onclick="ReAssign('valuationId', window.user)">Re-Assign</a>

There are a few extra things to note here, if you want more than a quick solution.

You looked like you were trying to use the + operator to combine strings in HTML. HTML is a scripting language, so when you're writing it, the whole thing is just a string itself. You can just skip these from now on, because it's not code your browser will be running (just a whole bunch of stuff, and anything that already exists is what has special meaning by the browser).

Next, you're using an anchor tag/link that doesn't actually take the user to another website, just runs some code. I'd use something else other than an anchor tag, with the appropriate CSS to format it to look the way you want. It really depends on the setting, but in many cases, a span tag will do. Give it a class (like class="runjs") and have a rule of CSS for that. To get it to imitate a link's behavior, use this:

.runjs {
    cursor: pointer;
    text-decoration: underline;
    color: blue;
}

This lets you leave out the href attribute which you weren't using anyways.

Last, you probably want to use JavaScript to set the value of this link's onclick attribute instead of hand writing it. It keeps your page cleaner by keeping the code of your page separate from what the structure of your page. In your class, you could change all these links like this...

var links = document.getElementsByClassName('runjs');
for(var i = 0; i < links.length; i++)
    links[i].onclick = function() { ReAssign('valuationId', window.user); };

While this won't work in some older browsers (because of the getElementsByClassName method), it's just three lines and does exactly what you're looking for. Each of these links has an anonymous function tied to them meaning they don't have any variable tied to them except that tag's onclick value. Plus if you wanted to, you could include more lines of code this way, all grouped up in one tidy location.

How can I select random files from a directory in bash?

I use this: it uses temporary file but goes deeply in a directory until it find a regular file and return it.

# find for a quasi-random file in a directory tree:

# directory to start search from:
ROOT="/";  

tmp=/tmp/mytempfile    
TARGET="$ROOT"
FILE=""; 
n=
r=
while [ -e "$TARGET" ]; do 
    TARGET="$(readlink -f "${TARGET}/$FILE")" ; 
    if [ -d "$TARGET" ]; then
      ls -1 "$TARGET" 2> /dev/null > $tmp || break;
      n=$(cat $tmp | wc -l); 
      if [ $n != 0 ]; then
        FILE=$(shuf -n 1 $tmp)
# or if you dont have/want to use shuf:
#       r=$(($RANDOM % $n)) ; 
#       FILE=$(tail -n +$(( $r + 1 ))  $tmp | head -n 1); 
      fi ; 
    else
      if [ -f "$TARGET"  ] ; then
        rm -f $tmp
        echo $TARGET
        break;
      else 
        # is not a regular file, restart:
        TARGET="$ROOT"
        FILE=""
      fi
    fi
done;

Travel/Hotel API's?

I've used the TripAdvisor API before and its suited me well. It returns, per destination, a list of top-rated hotels, along with options to retrieve reviews, photos, nearby restaurants and a couple other useful things.

http://www.tripadvisor.com/help/what_type_of_tripadvisor_content_is_available

From the API page (available API content) :

* Hotel, attraction and restaurant ratings and reviews
* Top 10 lists of hotels, attractions and restaurants in a destination
* Traveler photos of a destination
* Travelers' Choice award badges for hotels and destinations

To expand upon @nstehr's answer, you could also use Yahoo Pipes to facilitate a more granular local search. Go to pipes.yahoo.com and do a search for existing hotel pipes and you'll get the idea..

Using textures in THREE.js

Use TextureLoader to load a image as texture and then simply apply that texture to scene background.

 new THREE.TextureLoader();
     loader.load('https://images.pexels.com/photos/1205301/pexels-photo-1205301.jpeg' , function(texture)
                {
                 scene.background = texture;  
                });

Result:

https://codepen.io/hiteshsahu/pen/jpGLpq?editors=0011

See the Pen Flat Earth Three.JS by Hitesh Sahu (@hiteshsahu) on CodePen.

When should I use h:outputLink instead of h:commandLink?

I also see that the page loading (performance) takes a long time on using h:commandLink than h:link. h:link is faster compared to h:commandLink

How to display (print) vector in Matlab?

To print a vector which possibly has complex numbers-

fprintf('Answer: %s\n', sprintf('%d ', num2str(x)));

How to create a template function within a class? (C++)

The easiest way is to put the declaration and definition in the same file, but it may cause over-sized excutable file. E.g.

class Foo
{
public:
template <typename T> void some_method(T t) {//...}
}

Also, it is possible to put template definition in the separate files, i.e. to put them in .cpp and .h files. All you need to do is to explicitly include the template instantiation to the .cpp files. E.g.

// .h file
class Foo
{
public:
template <typename T> void some_method(T t);
}

// .cpp file
//...
template <typename T> void Foo::some_method(T t) 
{//...}
//...

template void Foo::some_method<int>(int);
template void Foo::some_method<double>(double);

Java URL encoding of query string parameters

Apache Http Components library provides a neat option for building and encoding query params -

With HttpComponents 4.x use - URLEncodedUtils

For HttpClient 3.x use - EncodingUtil

Javascript reduce() on Object

First of all, you don't quite get what's reduce's previous value is.

In you pseudo code you have return previous.value + current.value, therefore the previous value will be a number on the next call, not an object.

Second, reduce is an Array method, not an Object's one, and you can't rely on the order when you're iterating the properties of an object (see: https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Statements/for...in, this is applied to Object.keys too); so I'm not sure if applying reduce over an object makes sense.

However, if the order is not important, you can have:

Object.keys(obj).reduce(function(sum, key) {
    return sum + obj[key].value;
}, 0);

Or you can just map the object's value:

Object.keys(obj).map(function(key) { return this[key].value }, obj).reduce(function (previous, current) {
    return previous + current;
});

P.S. in ES6 with the fat arrow function's syntax (already in Firefox Nightly), you could shrink a bit:

Object.keys(obj).map(key => obj[key].value).reduce((previous, current) => previous + current);

How do I print uint32_t and uint16_t variables value?

The macros defined in <inttypes.h> are the most correct way to print values of types uint32_t, uint16_t, and so forth -- but they're not the only way.

Personally, I find those macros difficult to remember and awkward to use. (Given the syntax of a printf format string, that's probably unavoidable; I'm not claiming I could have come up with a better system.)

An alternative is to cast the values to a predefined type and use the format for that type.

Types int and unsigned int are guaranteed by the language to be at least 16 bits wide, and therefore to be able to hold any converted value of type int16_t or uint16_t, respectively. Similarly, long and unsigned long are at least 32 bits wide, and long long and unsigned long long are at least 64 bits wide.

For example, I might write your program like this (with a few additional tweaks):

#include <stdio.h>
#include <stdint.h>
#include <netinet/in.h>  

int main(void)
{
    uint32_t a=12, a1;
    uint16_t b=1, b1;
    a1 = htonl(a);
    printf("%lu---------%lu\n", (unsigned long)a, (unsigned long)a1);
    b1 = htons(b);
    printf("%u-----%u\n", (unsigned)b, (unsigned)b1);
    return 0;
}

One advantage of this approach is that it can work even with pre-C99 implementations that don't support <inttypes.h>. Such an implementation most likely wouldn't have <stdint.h> either, but the technique is useful for other integer types.

Deserialize JSON with Jackson into Polymorphic Types - A Complete Example is giving me a compile error

Handling polymorphism is either model-bound or requires lots of code with various custom deserializers. I'm a co-author of a JSON Dynamic Deserialization Library that allows for model-independent json deserialization library. The solution to OP's problem can be found below. Note that the rules are declared in a very brief manner.

public class SOAnswer {
    @ToString @Getter @Setter
    @AllArgsConstructor @NoArgsConstructor
    public static abstract class Animal {
        private String name;    
    }

    @ToString(callSuper = true) @Getter @Setter
    @AllArgsConstructor @NoArgsConstructor
    public static class Dog extends Animal {
        private String breed;
    }

    @ToString(callSuper = true) @Getter @Setter
    @AllArgsConstructor @NoArgsConstructor
    public static class Cat extends Animal {
        private String favoriteToy;
    }
    
    
    public static void main(String[] args) {
        String json = "[{"
                + "    \"name\": \"pluto\","
                + "    \"breed\": \"dalmatian\""
                + "},{"
                + "    \"name\": \"whiskers\","
                + "    \"favoriteToy\": \"mouse\""
                + "}]";
        
        // create a deserializer instance
        DynamicObjectDeserializer deserializer = new DynamicObjectDeserializer();
        
        // runtime-configure deserialization rules; 
        // condition is bound to the existence of a field, but it could be any Predicate
        deserializer.addRule(DeserializationRuleFactory.newRule(1, 
                (e) -> e.getJsonNode().has("breed"),
                DeserializationActionFactory.objectToType(Dog.class)));
        
        deserializer.addRule(DeserializationRuleFactory.newRule(1, 
                (e) -> e.getJsonNode().has("favoriteToy"),
                DeserializationActionFactory.objectToType(Cat.class)));
        
        List<Animal> deserializedAnimals = deserializer.deserializeArray(json, Animal.class);
        
        for (Animal animal : deserializedAnimals) {
            System.out.println("Deserialized Animal Class: " + animal.getClass().getSimpleName()+";\t value: "+animal.toString());
        }
    }
}

Maven depenendency for pretius-jddl (check newest version at maven.org/jddl:

<dependency>
  <groupId>com.pretius</groupId>
  <artifactId>jddl</artifactId>
  <version>1.0.0</version>
</dependency>

Get and Set a Single Cookie with Node.js HTTP Server

Using Some ES5/6 Sorcery & RegEx Magic

Here is an option to read the cookies and turn them into an object of Key, Value pairs for client side, could also use it server side.

Note: If there is a = in the value, no worries. If there is an = in the key, trouble in paradise.

More Notes: Some may argue readability so break it down as you like.

I Like Notes: Adding an error handler (try catch) wouldn't hurt.

const iLikeCookies = () => {
    return Object.fromEntries(document.cookie.split('; ').map(v => v.split(/=(.+)/))); 
}

const main = () => {
    // Add Test Cookies
    document.cookie = `name=Cookie Monster;expires=false;domain=localhost`
    document.cookie = `likesCookies=yes=withARandomEquals;expires=false;domain=localhost`;

    // Show the Objects
    console.log(document.cookie)
    console.log('The Object:', iLikeCookies())

    // Get a value from key
    console.log(`Username: ${iLikeCookies().name}`)
    console.log(`Enjoys Cookies: ${iLikeCookies().likesCookies}`)
}

enter image description here

What is going on?

iLikeCookies() will split the cookies by ; (space after ;):

["name=Cookie Monster", "likesCookies=yes=withARandomEquals"]

Then we map that array and split by first occurrence of = using regex capturing parens:

[["name", "Cookie Monster"], ["likesCookies", "yes=withARandomEquals"]]

Then use our friend `Object.fromEntries to make this an object of key, val pairs.

Nooice.

How to convert Set to Array?

I would prefer to start with removing duplications from an array and then try to sort. Return the 1st element from new array.

    function processData(myArray) {
        var s = new Set(myArray);
        var arr = [...s];
        return arr.sort((a,b) => b-a)[1];
    }
    
    console.log(processData([2,3,6,6,5]);

Unable to Build using MAVEN with ERROR - Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile

If JDK installed but still not working.

In Eclipse follow below steps:- Window --> Preference --> Installed JREs -->Change path of JRE to JDK(add).

Typescript: How to define type for a function callback (as any function type, not universal any) used in a method parameter

There are four abstract function types, you can use them separately when you know your function will take an argument(s) or not, will return a data or not.

export declare type fEmptyVoid = () => void;
export declare type fEmptyReturn = () => any;
export declare type fArgVoid = (...args: any[]) => void;
export declare type fArgReturn = (...args: any[]) => any;

like this:

public isValid: fEmptyReturn = (): boolean => true;
public setStatus: fArgVoid = (status: boolean): void => this.status = status;

For use only one type as any function type we can combine all abstract types together, like this:

export declare type fFunction = fEmptyVoid | fEmptyReturn | fArgVoid | fArgReturn;

then use it like:

public isValid: fFunction = (): boolean => true;
public setStatus: fFunction = (status: boolean): void => this.status = status;

In the example above everything is correct. But the usage example in bellow is not correct from the point of view of most code editors.

// you can call this function with any type of function as argument
public callArgument(callback: fFunction) {

    // but you will get editor error if call callback argument like this
    callback();
}

Correct call for editors is like this:

public callArgument(callback: fFunction) {

    // pay attention in this part, for fix editor(s) error
    (callback as fFunction)();
}

Nesting queries in SQL

The way I see it, the only place for a nested query would be in the WHERE clause, so e.g.

SELECT country.name, country.headofstate
FROM country 
WHERE country.headofstate LIKE 'A%' AND 
country.id in (SELECT country_id FROM city WHERE population > 100000)

Apart from that, I have to agree with Adrian on: why the heck should you use nested queries?

How to add a class to a given element?

You can use the API querySelector to select your element and then create a function with the element and the new classname as parameters. Using classlist for modern browsers, else for IE8. Then you can call the function after an event.

 //select the dom element
 var addClassVar = document.querySelector('.someclass');

 //define the addclass function
 var addClass = function(el,className){
   if (el.classList){
     el.classList.add(className);
   }
   else {
     el.className += ' ' + className;
  }
};

//call the function
addClass(addClassVar, 'newClass');

How to convert an address to a latitude/longitude?

Maptsraction (http://www.mapstraction.com) lets you choose between any number of geocoding services. This could be helpful if you need to do large quantities, as I know Google has a limit to how many you can do a day.

Regex that matches integers in between whitespace or start/end of string only

This just allow positive integers.

^[0-9]*[1-9][0-9]*$

How to figure out the SMTP server host?

Email tech support at your client's hosting provider and ask for the information.

Compiling a java program into an executable

We have found Jsmooth to be well-working and easily scriptable with ant under Linux. You may want to use one-jar (also easily scriptable with ant under Linux) to collect a multifile application in a single jar first.

We primarily needed the easy deployment of the EXE combined with the "hey, you need Java version X, go here to download" facilities.

(but what you most likely need is the "Runnable jar" / "Executable jar" facility in standard Java).

Select info from table where row has max date

SELECT group,MAX(date) as max_date
FROM table
WHERE checks>0
GROUP BY group

That works to get the max date..join it back to your data to get the other columns:

Select group,max_date,checks
from table t
inner join 
(SELECT group,MAX(date) as max_date
FROM table
WHERE checks>0
GROUP BY group)a
on a.group = t.group and a.max_date = date

Inner join functions as the filter to get the max record only.

FYI, your column names are horrid, don't use reserved words for columns (group, date, table).

Convert numpy array to tuple

Another option

tuple([tuple(row) for row in myarray])

If you are passing NumPy arrays to C++ functions, you may also wish to look at using Cython or SWIG.

No restricted globals

/* eslint no-restricted-globals:0 */

is another alternate approach

Converting Select results into Insert script - SQL Server

You can use an INSERT INTO SELECT statement, to insert the results of a select query into a table. http://www.w3schools.com/sql/sql_insert_into_select.asp

Example:

INSERT INTO Customers (CustomerName, Country) SELECT SupplierName, Country FROM Suppliers WHERE Country='Germany';

ConcurrentHashMap vs Synchronized HashMap

Synchronized HashMap:

  1. Each method is synchronized using an object level lock. So the get and put methods on synchMap acquire a lock.

  2. Locking the entire collection is a performance overhead. While one thread holds on to the lock, no other thread can use the collection.

ConcurrentHashMap was introduced in JDK 5.

  1. There is no locking at the object level,The locking is at a much finer granularity. For a ConcurrentHashMap, the locks may be at a hashmap bucket level.

  2. The effect of lower level locking is that you can have concurrent readers and writers which is not possible for synchronized collections. This leads to much more scalability.

  3. ConcurrentHashMap does not throw a ConcurrentModificationException if one thread tries to modify it while another is iterating over it.

This article Java 7: HashMap vs ConcurrentHashMap is a very good read. Highly recommended.

extract part of a string using bash/cut/split

What about sed? That will work in a single command:

sed 's#.*/\([^:]*\).*#\1#' <<<$string
  • The # are being used for regex dividers instead of / since the string has / in it.
  • .*/ grabs the string up to the last backslash.
  • \( .. \) marks a capture group. This is \([^:]*\).
    • The [^:] says any character _except a colon, and the * means zero or more.
  • .* means the rest of the line.
  • \1 means substitute what was found in the first (and only) capture group. This is the name.

Here's the breakdown matching the string with the regular expression:

        /var/cpanel/users/           joebloggs  :DNS9=domain.com joebloggs
sed 's#.*/                          \([^:]*\)   .*              #\1       #'

case-insensitive matching in xpath?

This does not work in Chrome Developer tools to locate a element, i am looking to locate the 'Submit' button in the screen

//input[matches(@value,'submit','i')]

However, using 'translate' to replace all caps to small works as below

//input[translate(@value,'ABCDEFGHIJKLMNOPQRSTUVWXYZ','abcdefghijklmnopqrstuvwxyz') = 'submit']

Update: I just found the reason why 'matches' doesnt work. I am using Chrome with xpath 1.0 which wont understand the syntax 'matches'. It should be xpath 2.0

What is meant by the term "hook" in programming?

In a generic sense, a "hook" is something that will let you, a programmer, view and/or interact with and/or change something that's already going on in a system/program.

For example, the Drupal CMS provides developers with hooks that let them take additional action after a "content node" is created. If a developer doesn't implement a hook, the node is created per normal. If a developer implements a hook, they can have some additional code run whenever a node is created. This code could do anything, including rolling back and/or altering the original action. It could also do something unrelated to the node creation entirely.

A callback could be thought of as a specific kind of hook. By implementing callback functionality into a system, that system is letting you call some additional code after an action has completed. However, hooking (as a generic term) is not limited to callbacks.

Another example. Sometimes Web Developers will refer to class names and/or IDs on elements as hooks. That's because by placing the ID/class name on an element, they can then use Javascript to modify that element, or "hook in" to the page document. (this is stretching the meaning, but it is commonly used and worth mentioning)

One line if in VB .NET

At the risk of causing some cringing by purests and c# programmers, you can use multiple statements and else in a one-line if statement in VB. In this example, y ends up 3 and not 7.

i = 1
If i = 1 Then x = 3 : y = 3 Else x = 7 : y = 7

How to submit a form using PhantomJS

Sending raw POST requests can be sometimes more convenient. Below you can see post.js original example from PhantomJS

// Example using HTTP POST operation

var page = require('webpage').create(),
    server = 'http://posttestserver.com/post.php?dump',
    data = 'universe=expanding&answer=42';

page.open(server, 'post', data, function (status) {
    if (status !== 'success') {
        console.log('Unable to post!');
    } else {
        console.log(page.content);
    }
    phantom.exit();
});

ValueError: unsupported format character while forming strings

I was using python interpolation and forgot the ending s character:

a = dict(foo='bar')
print("What comes after foo? %(foo)" % a) # Should be %(foo)s

Watch those typos.

length and length() in Java

Whenever an array is created, its size is specified. So length can be considered as a construction attribute. For String, it essentially a char array. Length is a property of the char array. There is no need to put length as a field, because not everything needs this field. http://www.programcreek.com/2013/11/start-from-length-length-in-java/

Nexus 7 not visible over USB via "adb devices" from Windows 7 x64

To fix/install Android USB driver on Windows 7/8 32bit/64bit:

  1. Connect your Android-powered device to your computer's USB port.
  2. Right-click on Computer from your desktop or Windows Explorer, and select Manage.
  3. Select Devices in the left pane.
  4. Locate and expand Other device in the right pane.
  5. Right-click the device name (Nexus 7 / Nexus 5 / Nexus 4) and select Update Driver Software. This will launch the Hardware Update Wizard.
  6. Select Browse my computer for driver software and click Next.
  7. Click Browse and locate the USB driver folder. (The Google USB Driver is located in <sdk>\extras\google\usb_driver\.)
  8. Click Next to install the driver.

If it still doesn't work try changing from MTP to PTP.

MTP -> PTP

How to sort by column in descending order in Spark SQL?

You can also sort the column by importing the spark sql functions

import org.apache.spark.sql.functions._
df.orderBy(asc("col1"))

Or

import org.apache.spark.sql.functions._
df.sort(desc("col1"))

importing sqlContext.implicits._

import sqlContext.implicits._
df.orderBy($"col1".desc)

Or

import sqlContext.implicits._
df.sort($"col1".desc)

String concatenation in MySQL

MySQL is different from most DBMSs use of + or || for concatenation. It uses the CONCAT function:

SELECT CONCAT(first_name, " ", last_name) AS Name FROM test.student

As @eggyal pointed out in comments, you can enable string concatenation with the || operator in MySQL by setting the PIPES_AS_CONCAT SQL mode.

PHP Unset Array value effect on other indexes

Test it yourself, but here's the output.

php -r '$a=array("a","b","c"); print_r($a); unset($a[1]); print_r($a);'
Array
(
    [0] => a
    [1] => b
    [2] => c
)
Array
(
    [0] => a
    [2] => c
)

Matrix multiplication using arrays

static int b[][]={{21,21},{22,22}};

static int a[][] ={{1,1},{2,2}};

public static void mul(){
    int c[][] = new int[2][2];

    for(int i=0;i<b.length;i++){
        for(int j=0;j<b.length;j++){
            c[i][j] =0;
        }   
    }

    for(int i=0;i<a.length;i++){
        for(int j=0;j<b.length;j++){
            for(int k=0;k<b.length;k++){
            c[i][j]= c[i][j] +(a[i][k] * b[k][j]);
            }
        }
    }

    for(int i=0;i<c.length;i++){
        for(int j=0;j<c.length;j++){
            System.out.print(c[i][j]);
        }   
        System.out.println("\n");
    }
}

Read from database and fill DataTable

Connection object is for illustration only. The DataAdapter is the key bit:

Dim strSql As String = "SELECT EmpCode,EmpID,EmpName FROM dbo.Employee"
Dim dtb As New DataTable
Using cnn As New SqlConnection(connectionString)
  cnn.Open()
  Using dad As New SqlDataAdapter(strSql, cnn)
    dad.Fill(dtb)
  End Using
  cnn.Close()
End Using

Simulating group_concat MySQL function in Microsoft SQL Server 2005?

Have a look at the GROUP_CONCAT project on Github, I think I does exactly what you are searching for:

This project contains a set of SQLCLR User-defined Aggregate functions (SQLCLR UDAs) that collectively offer similar functionality to the MySQL GROUP_CONCAT function. There are multiple functions to ensure the best performance based on the functionality required...

String Resource new line /n not possible?

After I tried next solution

  • add \n
  • add \n without spaces after it
  • use "" and press Enter inside text
  • text with press Enter
  • use lines=2

What solves me is br tag

<string name="successfullyfeatured">successfully<br/> You are now a member</string>

Update

the most reliable solution is to use Translation editor and edit text and it will handle new lines for you

Unable to install pyodbc on Linux

I needed all that, but I also needed python devel installed:

sudo yum install python-devel

Where is the itoa function in Linux?

glibc internal implementation

glibc 2.28 has an internal implementation:

which is used in several places internally, but I could not find if it can be exposed or how.

At least that should be a robust implementation if you are willing to extract it.

This question asks how to roll your own: How to convert an int to string in C?

Checking network connection

Try the operation you were attempting to do anyway. If it fails python should throw you an exception to let you know.

To try some trivial operation first to detect a connection will be introducing a race condition. What if the internet connection is valid when you test but goes down before you need to do actual work?

Checkbox angular material checked by default

Set this in HTML:

    <div class="modal-body " [formGroup]="Form">
        <div class="">
            <mat-checkbox formControlName="a" [disabled]="true"> Display 1</mat-checkbox>
        </div>
        <div class="">
            <mat-checkbox formControlName="b"  [disabled]="true">  Display 2 </mat-checkbox>
        </div>
        <div class="">
            <mat-checkbox formControlName="c"  [disabled]="true">  Display 3 </mat-checkbox>
        </div>
        <div class="">
            <mat-checkbox formControlName="d"  [disabled]="true">  Display 4</mat-checkbox>
        </div>
        <div class="">
            <mat-checkbox formControlName="e"  [disabled]="true"> Display 5 </mat-checkbox>
        </div>
    </div>

Changes in Ts file

this.Form = this.formBuilder.group({
a: false,
b: false,
c: false,
d: false,
e: false,
});

Conditionvalidation in Ur Business logic

if(true){
this.Form.patch(a: true);
}

What is the correct "-moz-appearance" value to hide dropdown arrow of a <select> element

This is it guys! FIXED!


Wait and see: https://bugzilla.mozilla.org/show_bug.cgi?id=649849

or workaround


For those wondering:

https://bugzilla.mozilla.org/show_bug.cgi?id=649849#c59

First, because the bug has a lot of hostile spam in it, it creates a hostile workplace for anyone who gets assigned to this.

Secondly, the person who has the ability to do this (which includes rewriting ) has been allocated to another project (b2g) for the time being and wont have time until that project get nearer to completion.

Third, even when that person has the time again, there is no guarantee that this will be a priority because, despite webkit having this, it breaks the spec for how is supposed to work (This is what I was told, I do not personally know the spec)

Now see https://wiki.mozilla.org/B2G/Schedule_Roadmap ;)


The page no longer exists and the bug hasn't be fixed but an acceptable workaround came from João Cunha, you guys can thank him for now!

How to make Unicode charset in cmd.exe by default?

Open an elevated Command Prompt (run cmd as administrator). query your registry for available TT fonts to the console by:

    REG query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Console\TrueTypeFont"

You'll see an output like :

    0    REG_SZ    Lucida Console
    00    REG_SZ    Consolas
    936    REG_SZ    *???
    932    REG_SZ    *MS ????

Now we need to add a TT font that supports the characters you need like Courier New, we do this by adding zeros to the string name, so in this case the next one would be "000" :

    REG ADD "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Console\TrueTypeFont" /v 000 /t REG_SZ /d "Courier New"

Now we implement UTF-8 support:

    REG ADD HKCU\Console /v CodePage /t REG_DWORD /d 65001 /f

Set default font to "Courier New":

    REG ADD HKCU\Console /v FaceName /t REG_SZ /d "Courier New" /f

Set font size to 20 :

    REG ADD HKCU\Console /v FontSize /t REG_DWORD /d 20 /f

Enable quick edit if you like :

    REG ADD HKCU\Console /v QuickEdit /t REG_DWORD /d 1 /f

What is the difference between static_cast<> and C style casting?

Since there are many different kinds of casting each with different semantics, static_cast<> allows you to say "I'm doing a legal conversion from one type to another" like from int to double. A plain C-style cast can mean a lot of things. Are you up/down casting? Are you reinterpreting a pointer?

Android: converting String to int

Change

try {
    myNum = Integer.parseInt(myString.getText().toString());
} catch(NumberFormatException nfe) {

to

try {
    myNum = Integer.parseInt(myString);
} catch(NumberFormatException nfe) {

Entity Framework code first unique column

In EF 6.2 using FluentAPI, you can use HasIndex()

modelBuilder.Entity<User>().HasIndex(u => u.UserName).IsUnique();

ImportError: No module named matplotlib.pyplot

Working on the django project and faced same problem, This is what I did. Check if you have metaplotlib already simply by writing pip show metaplotlib in the python terminal.

  1. If dont, run the command pip install metaplotlib.(make sure you have pip downloaded)
  2. Run the command pip show metaplotlib again.
  3. If the library is successfully downloaded, you can run your project (py manage.py runserver)

How do I convert hh:mm:ss.000 to milliseconds in Excel?

Using some text manipulation we can separate each unit of time and then sum them together with their millisecond coefficients.

To show the formulas in the cells use CTRL + `


Raw data view


Formula view

In C# check that filename is *possibly* valid (not that it exists)

There are several methods you could use that exist in the System.IO namespace:

Directory.GetLogicalDrives() // Returns an array of strings like "c:\"
Path.GetInvalidFileNameChars() // Returns an array of characters that cannot be used in a file name
Path.GetInvalidPathChars() // Returns an array of characters that cannot be used in a path.

As suggested you could then do this:

bool IsValidFilename(string testName) {
    string regexString = "[" + Regex.Escape(Path.GetInvalidPathChars()) + "]";
    Regex containsABadCharacter = new Regex(regexString);
    if (containsABadCharacter.IsMatch(testName)) {
        return false;
    }

    // Check for drive
    string pathRoot = Path.GetPathRoot(testName);
    if (Directory.GetLogicalDrives().Contains(pathRoot)) {
        // etc
    }

    // other checks for UNC, drive-path format, etc

    return true;
}

Open new popup window without address bars in firefox & IE

Check the mozilla documentation on window.open. The window features ("directory=...,...,height=350") etc. arguments should be a string:

window.open('/pageaddress.html','winname',"directories=0,titlebar=0,toolbar=0,location=0,status=0,menubar=0,scrollbars=no,resizable=no,width=400,height=350");

Try if that works in your browsers. Note that some of the features might be overridden by user preferences, such as "location" (see doc.)

Using group by and having clause

What type of sql database are using (MSSQL, Oracle etc)? I believe what you have written is correct.

You could also write the first query like this:

SELECT s.sid, s.name
FROM Supplier s
WHERE (SELECT COUNT(DISTINCT pr.jid)
       FROM Supplies su, Projects pr
       WHERE su.sid = s.sid 
           AND pr.jid = su.jid) >= 2

It's a little more readable, and less mind-bending than trying to do it with GROUP BY. Performance may differ though.

How to change the status bar background color and text color on iOS 7?

In iOS 7 the status bar doesn't have a background, therefore if you put a black 20px-high view behind it you will achieve the same result as iOS 6.

Also you may want to read the iOS 7 UI Transition Guide for further information on the subject.

How do I do an initial push to a remote repository with Git?

On server:

mkdir my_project.git
cd my_project.git
git --bare init

On client:

mkdir my_project
cd my_project
touch .gitignore
git init
git add .
git commit -m "Initial commit"
git remote add origin [email protected]:/path/to/my_project.git
git push origin master

Note that when you add the origin, there are several formats and schemas you could use. I recommend you see what your hosting service provides.

Plot data in descending order as appears in data frame

You want reorder(). Here is an example with dummy data

set.seed(42)
df <- data.frame(Category = sample(LETTERS), Count = rpois(26, 6))

require("ggplot2")

p1 <- ggplot(df, aes(x = Category, y = Count)) +
         geom_bar(stat = "identity")

p2 <- ggplot(df, aes(x = reorder(Category, -Count), y = Count)) +
         geom_bar(stat = "identity")

require("gridExtra")
grid.arrange(arrangeGrob(p1, p2))

Giving:

enter image description here

Use reorder(Category, Count) to have Category ordered from low-high.

How to output oracle sql result into a file in windows?

just to make the Answer 2 much easier, you can also define the folder where you can put your saved file

    spool /home/admin/myoutputfile.txt
    select * from table_name;
    spool off;

after that only with nano or vi myoutputfile.txt, you will see all the sql track.

hope is that help :)

Generating a WSDL from an XSD file

we can generate wsdl file from xsd but you have to use oracle enterprise pack of eclipse(OEPE). simply create xsd and then right click->new->wsdl...

C# Syntax - Example of a Lambda Expression - ForEach() over Generic List

Is this what you're asking for?

int[] numbers = { 1, 2, 3 };
numbers.ToList().ForEach(n => Console.WriteLine(n));

OS detecting makefile

Another way to do this is by using a "configure" script. If you are already using one with your makefile, you can use a combination of uname and sed to get things to work out. First, in your script, do:

UNAME=uname

Then, in order to put this in your Makefile, start out with Makefile.in which should have something like

UNAME=@@UNAME@@

in it.

Use the following sed command in your configure script after the UNAME=uname bit.

sed -e "s|@@UNAME@@|$UNAME|" < Makefile.in > Makefile

Now your makefile should have UNAME defined as desired. If/elif/else statements are all that's left!

Loading custom configuration files

the articles posted by Ricky are very good, but unfortunately they don't answer your question.

To solve your problem you should try this piece of code:

ExeConfigurationFileMap configMap = new ExeConfigurationFileMap();
configMap.ExeConfigFilename = @"d:\test\justAConfigFile.config.whateverYouLikeExtension";
Configuration config = ConfigurationManager.OpenMappedExeConfiguration(configMap, ConfigurationUserLevel.None);

If need to access a value within the config you can use the index operator:

config.AppSettings.Settings["test"].Value;

Naming conventions for Java methods that return boolean

I want to point a different view on this general naming convention, e.g.:

see java.util.Set: boolean add?(E e)

where the rationale is:

do some processing then report whether it succeeded or not.

While the return is indeed a boolean the method's name should point the processing to complete instead of the result type (boolean for this example).

Your createFreshSnapshot example seems for me more related to this point of view because seems to mean this: create a fresh-snapshot then report whether the create-operation succeeded. Considering this reasoning the name createFreshSnapshot seems to be the best one for your situation.

How to disable editing of elements in combobox for c#?

I tried ComboBox1_KeyPress but it allows to delete the character & you can also use copy paste command. My DropDownStyle is set to DropDownList but still no use. So I did below step to avoid combobox text editing.

  • Below code handles delete & backspace key. And also disables combination with control key (e.g. ctr+C or ctr+X)

     Private Sub CmbxInType_KeyDown(sender As Object, e As KeyEventArgs) Handles CmbxInType.KeyDown
        If e.KeyCode = Keys.Delete Or e.KeyCode = Keys.Back Then 
            e.SuppressKeyPress = True
        End If
    
        If Not (e.Control AndAlso e.KeyCode = Keys.C) Then
            e.SuppressKeyPress = True
        End If
    End Sub
    
  • In form load use below line to disable right click on combobox control to avoid cut/paste via mouse click.

    CmbxInType.ContextMenu = new ContextMenu()
    

printf a variable in C

Your printf needs a format string:

printf("%d\n", x);

This reference page gives details on how to use printf and related functions.

How to find list intersection?

Using list comprehensions is a pretty obvious one for me. Not sure about performance, but at least things stay lists.

[x for x in a if x in b]

Or "all the x values that are in A, if the X value is in B".

Is it possible to access to google translate api for free?

Yes, you can use GT for free. See the post with explanation. And look at repo on GitHub.

UPD 19.03.2019 Here is a version for browser on GitHub.

Found a swap file by the name

More info... Some times .swp files might be holded by vm that was running in backgroung. You may see permission denied message when try to delete the files.

Check and kill process vm

float:left; vs display:inline; vs display:inline-block; vs display:table-cell;

For the record only, to add to Spudley's answer, there is also the possibility to use position: absolute and margins if you know the column widths.

For me, the main issue when chossing a method is whether you need the columns to fill the whole height (equal heights), where table-cell is the easiest method (if you don't care much for older browsers).

What are the date formats available in SimpleDateFormat class?

Date and time formats are well described below

SimpleDateFormat (Java Platform SE 7) - Date and Time Patterns

There could be n Number of formats you can possibly make. ex - dd/MM/yyyy or YYYY-'W'ww-u or you can mix and match the letters to achieve your required pattern. Pattern letters are as follow.

  • G - Era designator (AD)
  • y - Year (1996; 96)
  • Y - Week Year (2009; 09)
  • M - Month in year (July; Jul; 07)
  • w - Week in year (27)
  • W - Week in month (2)
  • D - Day in year (189)
  • d - Day in month (10)
  • F - Day of week in month (2)
  • E - Day name in week (Tuesday; Tue)
  • u - Day number of week (1 = Monday, ..., 7 = Sunday)
  • a - AM/PM marker
  • H - Hour in day (0-23)
  • k - Hour in day (1-24)
  • K - Hour in am/pm (0-11)
  • h - Hour in am/pm (1-12)
  • m - Minute in hour (30)
  • s - Second in minute (55)
  • S - Millisecond (978)
  • z - General time zone (Pacific Standard Time; PST; GMT-08:00)
  • Z - RFC 822 time zone (-0800)
  • X - ISO 8601 time zone (-08; -0800; -08:00)

To parse:

2000-01-23T04:56:07.000+0000

Use: new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");

Cron and virtualenv

Running source from a cronfile won't work as cron uses /bin/sh as its default shell, which doesn't support source. You need to set the SHELL environment variable to be /bin/bash:

SHELL=/bin/bash
*/10 * * * * root source /path/to/virtualenv/bin/activate && /path/to/build/manage.py some_command > /dev/null

It's tricky to spot why this fails as /var/log/syslog doesn't log the error details. Best to alias yourself to root so you get emailed with any cron errors. Simply add yourself to /etc/aliases and run sendmail -bi.

More info here: http://codeinthehole.com/archives/43-Running-django-cronjobs-within-a-virtualenv.html

the link above is changed to: https://codeinthehole.com/tips/running-django-cronjobs-within-a-virtualenv/

How to calculate the intersection of two sets?

Yes there is retainAll check out this

Set<Type> intersection = new HashSet<Type>(s1);
intersection.retainAll(s2);

Clearing state es6 React

First, you'll need to store your initial state when using the componentWillMount() function from the component lifecycle:

componentWillMount() {
    this.initialState = this.state
}

This stores your initial state and can be used to reset the state whenever you need by calling

this.setState(this.initialState)

List of swagger UI alternatives

Yes, there are a few of them.

Hosted solutions that support swagger:

Check the following articles for more details:

Does MySQL foreign_key_checks affect the entire database?

As explained by Ron, there are two variables, local and global. The local variable is always used, and is the same as global upon connection.

SET FOREIGN_KEY_CHECKS=0;
SET GLOBAL FOREIGN_KEY_CHECKS=0;

SHOW Variables WHERE Variable_name='foreign_key_checks'; # always shows local variable

When setting the GLOBAL variable, the local one isn't changed for any existing connections. You need to reconnect or set the local variable too.

Perhaps unintuitive, MYSQL does not enforce foreign keys when FOREIGN_KEY_CHECKS are re-enabled. This makes it possible to create an inconsistent database even though foreign keys and checks are on.

If you want your foreign keys to be completely consistent, you need to add the keys while checking is on.

Is there a way to reset IIS 7.5 to factory settings?

Resetting IIS

  1. On the computer that is running Microsoft Dynamics NAV Web Server components, open a command prompt as an administrator as follows:

a. From the Start menu, choose All Programs, and then choose Accessories. b. Right-click Command Prompt, and then choose Run as administrator.

  1. At the command prompt, type the following command to change to the Microsoft.NET\Framework64\v4.0.30319 folder, and then press Enter.

  2. cd\Windows\Microsoft.NET\Framework64\v4.0.30319

  3. At the command prompt, type the following command, and then press Enter.

  4. aspnet_regiis.exe -iru

  5. At the command prompt, type the following command, and then press Enter. iisreset

How to convert AAR to JAR

For those, who want to do it automatically, I have wrote a little two-lines bash script which does next two things:

  1. Looks for all *.aar files and extracts classes.jar from them
  2. Renames extracted classes.jar to be like the aar but with a new extension

    find . -name '*.aar' -exec sh -c 'unzip -d `dirname {}` {} classes.jar' \;
    find . -name '*.aar' -exec sh -c 'mv `dirname {}`/classes.jar `echo {} | sed s/aar/jar/g`' \;
    

That's it!

Where's my JSON data in my incoming Django request?

If you are posting JSON to Django, I think you want request.body (request.raw_post_data on Django < 1.4). This will give you the raw JSON data sent via the post. From there you can process it further.

Here is an example using JavaScript, jQuery, jquery-json and Django.

JavaScript:

var myEvent = {id: calEvent.id, start: calEvent.start, end: calEvent.end,
               allDay: calEvent.allDay };
$.ajax({
    url: '/event/save-json/',
    type: 'POST',
    contentType: 'application/json; charset=utf-8',
    data: $.toJSON(myEvent),
    dataType: 'text',
    success: function(result) {
        alert(result.Result);
    }
});

Django:

def save_events_json(request):
    if request.is_ajax():
        if request.method == 'POST':
            print 'Raw Data: "%s"' % request.body   
    return HttpResponse("OK")

Django < 1.4:

  def save_events_json(request):
    if request.is_ajax():
        if request.method == 'POST':
            print 'Raw Data: "%s"' % request.raw_post_data
    return HttpResponse("OK")

How to obtain the last index of a list?

Did you mean len(list1)-1?

If you're searching for other method, you can try list1.index(list1[-1]), but I don't recommend this one. You will have to be sure, that the list contains NO duplicates.

creating custom tableview cells in swift

Uncheck "Size Classes" checkbox works for me as well, but you could also add the missing constraints in the interface builder. Just use the built-in function if you don't want to add the constraints on your own. Using constraints is - in my opinion - the better way because the layout is independent from the device (iPhone or iPad).

Parse Error: Adjacent JSX elements must be wrapped in an enclosing tag

React 16 gets your return as an array so it should be wrapped by one element like div.

Wrong Approach

render(){
    return(
    <input type="text" value="" onChange={this.handleChange} />

     <button className="btn btn-primary" onClick=   {()=>this.addTodo(this.state.value)}>Submit</button>

    );
}

Right Approach (All elements in one div or other element you are using)

render(){
    return(
        <div>
            <input type="text" value="" onChange={this.handleChange} />

            <button className="btn btn-primary" onClick={()=>this.addTodo(this.state.value)}>Submit</button>
        </div>
    );
}

How to add multiple font files for the same font?

To have font variation working correctly, I had to reverse the order of @font-face in CSS.

@font-face {
    font-family: "DejaVuMono";
    src: url("styles/DejaVuSansMono-BoldOblique.ttf");
    font-weight: bold;
    font-style: italic, oblique;
}   
@font-face {
    font-family: "DejaVuMono";
    src: url("styles/DejaVuSansMono-Oblique.ttf");
    font-style: italic, oblique;
}
@font-face {
    font-family: "DejaVuMono";
    src: url("styles/DejaVuSansMono-Bold.ttf");
    font-weight: bold;
}
 @font-face {
    font-family: "DejaVuMono";
    src: url("styles/DejaVuSansMono.ttf");
}

What is the best way to implement "remember me" for a website?

I would store a user ID and a token. When the user comes back to the site, compare those two pieces of information against something persistent like a database entry.

As for security, just don't put anything in there that will allow someone to modify the cookie to gain extra benefits. For example, don't store their user groups or their password. Anything that can be modified that would circumvent your security should not be stored in the cookie.

git - remote add origin vs remote set-url origin

  • When you run git remote add origin [email protected]:User/UserRepo.git, then a new remote created named origin.
  • When you run git remote set-url origin [email protected]:User/UserRepo.git,git searches for existing remote having name origin and change it's remote repository url. If git unable to find any remote having name origin, It raise an error fatal: No such remote 'origin'.

If you are going to create a new repository then use git remote add origin [email protected]:User/UserRepo.git to add remote.

How do I get row id of a row in sql server

SQL Server does not track the order of inserted rows, so there is no reliable way to get that information given your current table structure. Even if employee_id is an IDENTITY column, it is not 100% foolproof to rely on that for order of insertion (since you can fill gaps and even create duplicate ID values using SET IDENTITY_INSERT ON). If employee_id is an IDENTITY column and you are sure that rows aren't manually inserted out of order, you should be able to use this variation of your query to select the data in sequence, newest first:

SELECT 
   ROW_NUMBER() OVER (ORDER BY EMPLOYEE_ID DESC) AS ID, 
   EMPLOYEE_ID,
   EMPLOYEE_NAME 
FROM dbo.CSBCA1_5_FPCIC_2012_EES207201222743
ORDER BY ID;

You can make a change to your table to track this information for new rows, but you won't be able to derive it for your existing data (they will all me marked as inserted at the time you make this change).

ALTER TABLE dbo.CSBCA1_5_FPCIC_2012_EES207201222743 
-- wow, who named this?
  ADD CreatedDate DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP;

Note that this may break existing code that just does INSERT INTO dbo.whatever SELECT/VALUES() - e.g. you may have to revisit your code and define a proper, explicit column list.

How to get Url Hash (#) from server side

Just to rule out the possibility you aren't actually trying to see the fragment on a GET/POST and actually want to know how to access that part of a URI object you have within your server-side code, it is under Uri.Fragment (MSDN docs).

Java math function to convert positive int to negative and negative to positive?

You can use the minus operator or Math.abs. These work for all negative integers EXCEPT for Integer.MIN_VALUE! If you do 0 - MIN_VALUE the answer is still MIN_VALUE.

Arrays with different datatypes i.e. strings and integers. (Objectorientend)

@NoCanDo: You cannot create an array with different data types because java only supports variables with a specific data type or object. When you are creating an array, you are pulling together an assortment of similar variables -- almost like an extended variable. All of the variables must be of the same type therefore. Java cannot differentiate the data type of your variable unless you tell it what it is. Ex: int tells all your variables declared to it are of data type int. What you could do is create 3 arrays with corresponding information.

int bookNumber[] = {1, 2, 3, 4, 5};
int bookName[] = {nameOfBook1, nameOfBook2, nameOfBook3, nameOfBook4, nameOfBook5} // etc.. etc..

Now, a single index number gives you all the info for that book. Ex: All of your arrays with index number 0 ([0]) have information for book 1.

How to delete specific columns with VBA?

To answer the question How to delete specific columns in vba for excel. I use Array as below.

sub del_col()

dim myarray as variant
dim i as integer

myarray = Array(10, 9, 8)'Descending to Ascending
For i = LBound(myarray) To UBound(myarray)
    ActiveSheet.Columns(myarray(i)).EntireColumn.Delete
Next i

end sub

Commenting out a set of lines in a shell script

As per this site:

#!/bin/bash
foo=bar
: '
This is a test comment
Author foo bar
Released under GNU 
'

echo "Init..."
# rest of script

CSS how to make an element fade in and then fade out?

I found this link to be useful: css-tricks fade-in fade-out css.

Here's a summary of the csstricks post:

CSS classes:

.m-fadeOut {
  visibility: hidden;
  opacity: 0;
  transition: visibility 0s linear 300ms, opacity 300ms;
}
.m-fadeIn {
  visibility: visible;
  opacity: 1;
  transition: visibility 0s linear 0s, opacity 300ms;
}

In React:

toggle(){
    if(true condition){
        this.setState({toggleClass: "m-fadeIn"});
    }else{
        this.setState({toggleClass: "m-fadeOut"});
    }
}

render(){
    return (<div className={this.state.toggleClass}>Element to be toggled</div>)
}

Why is this HTTP request not working on AWS Lambda?

I faced this issue on Node 10.X version. below is my working code.

const https = require('https');

exports.handler = (event,context,callback) => {
    let body='';
    let jsonObject = JSON.stringify(event);

    // the post options
    var optionspost = {
      host: 'example.com', 
      path: '/api/mypath',
      method: 'POST',
      headers: {
      'Content-Type': 'application/json',
      'Authorization': 'blah blah',
    }
    };

    let reqPost =  https.request(optionspost, function(res) {
        console.log("statusCode: ", res.statusCode);
        res.on('data', function (chunk) {
            body += chunk;
        });
        res.on('end', function () {
           console.log("Result", body.toString());
           context.succeed("Sucess")
        });
        res.on('error', function () {
          console.log("Result Error", body.toString());
          context.done(null, 'FAILURE');
        });
    });
    reqPost.write(jsonObject);
    reqPost.end();
};

how to get right offset of an element? - jQuery

Alex, Gary:

As requested, here is my comment posted as an answer:

var rt = ($(window).width() - ($whatever.offset().left + $whatever.outerWidth()));

Thanks for letting me know.

In pseudo code that can be expressed as:

The right offset is:

The window's width MINUS
( The element's left offset PLUS the element's outer width )

How to Execute SQL Server Stored Procedure in SQL Developer?

Select * from Table name ..i.e(are you save table name in sql(TEST) k.

Select * from TEST then you will execute your project.

Subset dataframe by multiple logical conditions of rows to remove

This answer is more meant to explain why, not how. The '==' operator in R is vectorized in a same way as the '+' operator. It matches the elements of whatever is on the left side to the elements of whatever is on the right side, per element. For example:

> 1:3 == 1:3
[1] TRUE TRUE TRUE

Here the first test is 1==1 which is TRUE, the second 2==2 and the third 3==3. Notice that this returns a FALSE in the first and second element because the order is wrong:

> 3:1 == 1:3
[1] FALSE  TRUE FALSE

Now if one object is smaller then the other object then the smaller object is repeated as much as it takes to match the larger object. If the size of the larger object is not a multiplication of the size of the smaller object you get a warning that not all elements are repeated. For example:

>  1:2 == 1:3
[1]  TRUE  TRUE FALSE
Warning message:
In 1:2 == 1:3 :
  longer object length is not a multiple of shorter object length

Here the first match is 1==1, then 2==2, and finally 1==3 (FALSE) because the left side is smaller. If one of the sides is only one element then that is repeated:

> 1:3 == 1
[1]  TRUE FALSE FALSE

The correct operator to test if an element is in a vector is indeed '%in%' which is vectorized only to the left element (for each element in the left vector it is tested if it is part of any object in the right element).

Alternatively, you can use '&' to combine two logical statements. '&' takes two elements and checks elementwise if both are TRUE:

> 1:3 == 1 & 1:3 != 2
[1]  TRUE FALSE FALSE

java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter

check jar files in your project which are mentioned in config.ini if not proper then install manually and then follow the following steps:

  1. Select your product configuration file, right-click on it and select Run As Run Configurations
  2. Select "Validate plug-ins prior to launching". This will check if you have all required plug-ins in your run configuration. If this check reports that some plug-ins are missing, try clicking the "Add Required-Plug-Ins" button. Also make sure to define all dependencies in your product. And your application start running

How to read existing text files without defining path

You need to decide which directory you want the file to be relative to. Once you have done that, you construct the full path like this:

string fullPathToFile = Path.Combine(dir, fileName);

If you don't supply the base directory dir then you will be at the total mercy of whatever happens to the working directory of your process. That is something that can be out of your control. For example, shortcuts to your application may specify it. Using file dialogs can change it.

For a console application it is reasonable to use relative files directly because console applications are designed so that the working directory is a critical input and is a well-defined part of the execution environment. However, for a GUI app that is not the case which is why I recommend you explicitly convert your relative file name to a full absolute path using some well-defined base directory.

Now, since you have a console application, it is reasonable for you to use a relative path, provided that the expectation is that the files in question will be located in the working directory. But it would be very common for that not to be the case. Normally the working directory is used to specify where the user's input and output files are to be stored. It does not typically point to the location where the program's files are.

One final option is that you don't attempt to deploy these program files as external text files. Perhaps a better option is to link them to the executable as resources. That way they are bound up with the executable and you can completely side-step this issue.

What is .htaccess file?

Below are some usage of htaccess files in server:

1) AUTHORIZATION, AUTHENTICATION: .htaccess files are often used to specify the security restrictions for the particular directory, hence the filename "access". The .htaccess file is often accompanied by an .htpasswd file which stores valid usernames and their passwords.

2) CUSTOMIZED ERROR RESPONSES: Changing the page that is shown when a server-side error occurs, for example HTTP 404 Not Found. Example : ErrorDocument 404 /notfound.html

3) REWRITING URLS: Servers often use .htaccess to rewrite "ugly" URLs to shorter and prettier ones.

4) CACHE CONTROL: .htaccess files allow a server to control User agent caching used by web browsers to reduce bandwidth usage, server load, and perceived lag.

More info : http://en.wikipedia.org/wiki/Htaccess

How to access child's state in React?

As the previous answers saids, try to move the state to a top component and modify the state through callbacks passed to it's children.

In case that you really need to access to a child state that is declared as a functional component (hooks) you can declare a ref in the parent component, then pass it as a ref attribute to the child but you need to use React.forwardRef and then the hook useImperativeHandle to declare a function you can call in the parent component.

Take a look at the following example:

const Parent = () => {
    const myRef = useRef();
    return <Child ref={myRef} />;
}

const Child = React.forwardRef((props, ref) => {
    const [myState, setMyState] = useState('This is my state!');
    useImperativeHandle(ref, () => ({getMyState: () => {return myState}}), [myState]);
})

Then you should be able to get myState in the Parent component by calling: myRef.current.getMyState();

Time comparison

        String timeRange = "12:24-13:24";
        String[] timeR = timeRange.trim().split("-");
        
        // java 8
        LocalTime start = LocalTime.parse(timeR[0].trim());
        LocalTime end = LocalTime.parse(timeR[1].trim());
        LocalTime current = LocalTime.now();
        LocalTime currentHM = LocalTime.parse(current.getHour()+":"+current.getMinute());
        
        
        if(!currentHM.isBefore(start) && !currentHM.isAfter(end)) {
            return true;
        }else {
            return false;
        }

login failed for user 'sa'. The user is not associated with a trusted SQL Server connection. (Microsoft SQL Server, Error: 18452) in sql 2008

  1. First make sure sa is enabled
  2. Change the authontication mode to mixed mode (Window and SQL authentication)
  3. Stop your SQL Server
  4. Restart your SQL Server

Anaconda site-packages

You should find installed packages in :

anaconda's directory / lib / site_packages

That's where i found mine.

GCC: array type has incomplete element type

The compiler needs to know the size of the second dimension in your two dimensional array. For example:

void print_graph(g_node graph_node[], double weight[][5], int nodes);

Create two-dimensional arrays and access sub-arrays in Ruby

Here is the simple version

 #one
 a = [[0]*10]*10

 #two
row, col = 10, 10
a = [[0]*row]*col

Running Groovy script from the command line

#!/bin/sh
sed '1,2d' "$0"|$(which groovy) /dev/stdin; exit;

println("hello");

How do I extract a substring from a string until the second space is encountered?

Just use String.IndexOf twice as in:

     string str = "My Test String";
     int index = str.IndexOf(' ');
     index = str.IndexOf(' ', index + 1);
     string result = str.Substring(0, index);

PyCharm import external library

Answer for PyCharm 2016.1 on OSX: (This is an update to the answer by @GeorgeWilliams993's answer above, but I don't have the rep yet to make comments.)

Go to Pycharm menu --> Preferences --> Project: (projectname) --> Project Interpreter

At the top is a popup for "Project Interpreter," and to the right of it is a button with ellipses (...) - click on this button for a different popup and choose "More" (or, as it turns out, click on the main popup and choose "Show All").

This shows a list of interpreters, with one selected. At the bottom of the screen are a set of tools... pick the rightmost one:

Show path for the selected interpreter button

Now you should see all the paths pycharm is searching to find imports, and you can use the "+" button at the bottom to add a new path.

I think the most significant difference from @GeorgeWilliams993's answer is that the gear button has been replaced by a set of ellipses. That threw me off.

cpp / c++ get pointer value or depointerize pointer

To get the value of a pointer, just de-reference the pointer.

int *ptr;
int value;
*ptr = 9;

value = *ptr;

value is now 9.

I suggest you read more about pointers, this is their base functionality.

Insecure content in iframe on secure page

Based on generality of this question, I think, that you'll need to setup your own HTTPS proxy on some server online. Do the following steps:

  • Prepare your proxy server - install IIS, Apache
  • Get valid SSL certificate to avoid security errors (free from startssl.com for example)
  • Write a wrapper, which will download insecure content (how to below)
  • From your site/app get https://yourproxy.com/?page=http://insecurepage.com

If you simply download remote site content via file_get_contents or similiar, you can still have insecure links to content. You'll have to find them with regex and also replace. Images are hard to solve, but Ï found workaround here: http://foundationphp.com/tutorials/image_proxy.php


Note: While this solution may have worked in some browsers when it was written in 2014, it no longer works. Navigating or redirecting to an HTTP URL in an iframe embedded in an HTTPS page is not permitted by modern browsers, even if the frame started out with an HTTPS URL.

The best solution I created is to simply use google as the ssl proxy...

https://www.google.com/search?q=%http://yourhttpsite.com&btnI=Im+Feeling+Lucky

Tested and works in firefox.

Other Methods:

  • Use a Third party such as embed.ly (but it it really only good for well known http APIs).

  • Create your own redirect script on an https page you control (a simple javascript redirect on a relative linked page should do the trick. Something like: (you can use any langauge/method)

    https://example.com That has a iframe linking to...

    https://example.com/utilities/redirect.html Which has a simple js redirect script like...

    document.location.href ="http://thenonsslsite.com";

  • Alternatively, you could add an RSS feed or write some reader/parser to read the http site and display it within your https site.

  • You could/should also recommend to the http site owner that they create an ssl connection. If for no other reason than it increases seo.

Unless you can get the http site owner to create an ssl certificate, the most secure and permanent solution would be to create an RSS feed grabing the content you need (presumably you are not actually 'doing' anything on the http site -that is to say not logging in to any system).

The real issue is that having http elements inside a https site represents a security issue. There are no completely kosher ways around this security risk so the above are just current work arounds.

Note, that you can disable this security measure in most browsers (yourself, not for others). Also note that these 'hacks' may become obsolete over time.

java : convert float to String and String to float

Float to string - String.valueOf()

float amount=100.00f;
String strAmount=String.valueOf(amount);
// or  Float.toString(float)

String to Float - Float.parseFloat()

String strAmount="100.20";
float amount=Float.parseFloat(strAmount)
// or  Float.valueOf(string)

Can I multiply strings in Java to repeat sequences?

I created a method that do the same thing you want, feel free to try this:

public String repeat(String s, int count) {
    return count > 0 ? s + repeat(s, --count) : "";
}

CodeIgniter activerecord, retrieve last insert id?

for Specific table you cannot use $this->db->insert_id() . even the last insert happened long ago it can be fetched like this. may be wrong. but working well for me

     $this->db->select_max('{primary key}');
     $result= $this->db->get('{table}')->row_array();
     echo $result['{primary key}'];