Programs & Examples On #Labview

LabVIEW stands for Laboratory Virtual Instrumentation Engineering Workbench and is a graphical programming system by National Instruments. The programming language is called G but often referred to as just LabVIEW.

What is the worst programming language you ever worked with?

Worst Programming Language? - Brainfuck

I haven't worked with it myself, but I would call it the worst. It's generally used as a challenge though, not for production (more like: I'm bored this weekend, let's see if I can re-write tic tac toe in it). Check out it's Hello World program on wiki.

How to get the values of a ConfigurationSection of type NameValueSectionHandler

Here's a good post that shows how to do it.

If you want to read the values from a file other than the app.config, you need to load it into the ConfigurationManager.

Try this method: ConfigurationManager.OpenMappedExeConfiguration()

There's an example of how to use it in the MSDN article.

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

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

How to get jSON response into variable from a jquery script

Look out for this pitfal: http://www.vertstudios.com/blog/avoiding-ajax-newline-pitfall/

Searched several houres before I found there were some linebreaks in the included files.

Calculate Pandas DataFrame Time Difference Between Two Columns in Hours and Minutes

Pandas timestamp differences returns a datetime.timedelta object. This can easily be converted into hours by using the *as_type* method, like so

import pandas
df = pandas.DataFrame(columns=['to','fr','ans'])
df.to = [pandas.Timestamp('2014-01-24 13:03:12.050000'), pandas.Timestamp('2014-01-27 11:57:18.240000'), pandas.Timestamp('2014-01-23 10:07:47.660000')]
df.fr = [pandas.Timestamp('2014-01-26 23:41:21.870000'), pandas.Timestamp('2014-01-27 15:38:22.540000'), pandas.Timestamp('2014-01-23 18:50:41.420000')]
(df.fr-df.to).astype('timedelta64[h]')

to yield,

0    58
1     3
2     8
dtype: float64

Converting array to list in Java

It seems little late but here are my two cents. We cannot have List<int> as int is a primitive type so we can only have List<Integer>.

Java 8 (int array)

int[] ints = new int[] {1,2,3,4,5};
List<Integer> list11 =Arrays.stream(ints).boxed().collect(Collectors.toList()); 

Java 8 and below (Integer array)

Integer[] integers = new Integer[] {1,2,3,4,5};
List<Integer> list21 =  Arrays.asList(integers); // returns a fixed-size list backed by the specified array.
List<Integer> list22 = new ArrayList<>(Arrays.asList(integers)); // good
List<Integer> list23 = Arrays.stream(integers).collect(Collectors.toList()); //Java 8 only

Need ArrayList and not List?

In case we want a specific implementation of List e.g. ArrayList then we can use toCollection as:

ArrayList<Integer> list24 = Arrays.stream(integers)
                          .collect(Collectors.toCollection(ArrayList::new));

Why list21 cannot be structurally modified?

When we use Arrays.asList the size of the returned list is fixed because the list returned is not java.util.ArrayList, but a private static class defined inside java.util.Arrays. So if we add or remove elements from the returned list, an UnsupportedOperationException will be thrown. So we should go with list22 when we want to modify the list. If we have Java8 then we can also go with list23.

To be clear list21 can be modified in sense that we can call list21.set(index,element) but this list may not be structurally modified i.e. cannot add or remove elements from the list. You can also check this answer of mine for more explanation.


If we want an immutable list then we can wrap it as:

List<Integer> list22 = Collections.unmodifiableList(Arrays.asList(integers));

Another point to note is that the method Collections.unmodifiableList returns an unmodifiable view of the specified list. An unmodifiable view collection is a collection that is unmodifiable and is also a view onto a backing collection. Note that changes to the backing collection might still be possible, and if they occur, they are visible through the unmodifiable view.

We can have a truly immutable list in Java 9 and 10.

Truly Immutable list

Java 9:

String[] objects = {"Apple", "Ball", "Cat"};
List<String> objectList = List.of(objects);

Java 10 (Truly Immutable list):

We can use List.of introduced in Java 9. Also other ways:

  1. List.copyOf(Arrays.asList(integers))
  2. Arrays.stream(integers).collect(Collectors.toUnmodifiableList());

How to export a mysql database using Command Prompt?

Go to command prompt at this path,

C:\Program Files (x86)\MySQL\MySQL Server 5.0\bin>

Then give this command to export your database (no space after -p)

mysqldump -u[username] -p[userpassword] yourdatabase > [filepath]wantedsqlfile.sql

View a specific Git commit

git show <revhash>

Documentation here. Or if that doesn't work, try Google Code's GIT Documentation

How to read values from properties file?

There are various ways to achieve the same. Below are some commonly used ways in spring-

  1. Using PropertyPlaceholderConfigurer

  2. Using PropertySource

  3. Using ResourceBundleMessageSource

  4. Using PropertiesFactoryBean

    and many more........................

Assuming ds.type is key in your property file.


Using PropertyPlaceholderConfigurer

Register PropertyPlaceholderConfigurer bean-

<context:property-placeholder location="classpath:path/filename.properties"/>

or

<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
  <property name="locations" value="classpath:path/filename.properties" ></property>
</bean>

or

@Configuration
public class SampleConfig {
 @Bean
 public static PropertySourcesPlaceholderConfigurer placeHolderConfigurer() {
  return new PropertySourcesPlaceholderConfigurer();
  //set locations as well.
 }
}

After registering PropertySourcesPlaceholderConfigurer, you can access the value-

@Value("${ds.type}")private String attr; 

Using PropertySource

In the latest spring version you don't need to register PropertyPlaceHolderConfigurer with @PropertySource, I found a good link to understand version compatibility-

@PropertySource("classpath:path/filename.properties")
@Component
public class BeanTester {
    @Autowired Environment environment; 
    public void execute() {
        String attr = this.environment.getProperty("ds.type");
    }
}

Using ResourceBundleMessageSource

Register Bean-

<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
  <property name="basenames">
    <list>
      <value>classpath:path/filename.properties</value>
    </list>
  </property>
</bean>

Access Value-

((ApplicationContext)context).getMessage("ds.type", null, null);

or

@Component
public class BeanTester {
    @Autowired MessageSource messageSource; 
    public void execute() {
        String attr = this.messageSource.getMessage("ds.type", null, null);
    }
}

Using PropertiesFactoryBean

Register Bean-

<bean id="properties"
      class="org.springframework.beans.factory.config.PropertiesFactoryBean">
  <property name="locations">
    <list>
      <value>classpath:path/filename.properties</value>
    </list>
  </property>
</bean>

Wire Properties instance into your class-

@Component
public class BeanTester {
    @Autowired Properties properties; 
    public void execute() {
        String attr = properties.getProperty("ds.type");
    }
}

Archive the artifacts in Jenkins

In Jenkins 2.60.3 there is a way to delete build artifacts (not the archived artifacts) in order to save hard drive space on the build machine. In the General section, check "Discard old builds" with strategy "Log Rotation" and then go into its Advanced options. Two more options will appear related to keeping build artifacts for the job based on number of days or builds.

The settings that work for me are to enter 1 for "Max # of builds to keep with artifacts" and then to have a post-build action to archive the artifacts. This way, all artifacts from all builds will be archived, all information from builds will be saved, but only the last build will keep its own artifacts.

Discard old builds options

Matplotlib connect scatterplot points with line - Python

In addition to what provided in the other answers, the keyword "zorder" allows one to decide the order in which different objects are plotted vertically. E.g.:

plt.plot(x,y,zorder=1) 
plt.scatter(x,y,zorder=2)

plots the scatter symbols on top of the line, while

plt.plot(x,y,zorder=2)
plt.scatter(x,y,zorder=1)

plots the line over the scatter symbols.

See, e.g., the zorder demo

How to clear memory to prevent "out of memory error" in excel vba?

If you operate on a large dataset, it is very possible that arrays will be used. For me creating a few arrays from 500 000 rows and 30 columns worksheet caused this error. I solved it simply by using the line below to get rid of array which is no longer necessary to me, before creating another one:

Erase vArray

Also if only 2 columns out of 30 are used, it is a good idea to create two 1-column arrays instead of one with 30 columns. It doesn't affect speed, but there will be a difference in memory usage.

Is it possible to read from a InputStream with a timeout?

I have not used the classes from the Java NIO package, but it seems they might be of some help here. Specifically, java.nio.channels.Channels and java.nio.channels.InterruptibleChannel.

Java check to see if a variable has been initialized

Instance variables or fields, along with static variables, are assigned default values based on the variable type:

  • int: 0
  • char: \u0000 or 0
  • double: 0.0
  • boolean: false
  • reference: null

Just want to clarify that local variables (ie. declared in block, eg. method, for loop, while loop, try-catch, etc.) are not initialized to default values and must be explicitly initialized.

How to start Activity in adapter?

When implementing the onClickListener, you can use v.getContext.startActivity.

btn.setOnClickListener(new OnClickListener() {                  
    @Override
    public void onClick(View v) {
        v.getContext().startActivity(PUT_YOUR_INTENT_HERE);
    }
});

How to truncate the time on a DateTime object in Python?

Use a date not a datetime if you dont care about the time.

>>> now = datetime.now()
>>> now.date()
datetime.date(2011, 3, 29)

You can update a datetime like this:

>>> now.replace(minute=0, hour=0, second=0, microsecond=0)
datetime.datetime(2011, 3, 29, 0, 0)

How long is the SHA256 hash?

I prefer to use BINARY(32) since it's the optimized way!

You can place in that 32 hex digits from (00 to FF).

Therefore BINARY(32)!

Is it possible to CONTINUE a loop from an exception?

In the construct you have provided, you don't need a CONTINUE. Once the exception is handled, the statement after the END is performed, assuming your EXCEPTION block doesn't terminate the procedure. In other words, it will continue on to the next iteration of the user_rec loop.

You also need to SELECT INTO a variable inside your BEGIN block:

SELECT attr INTO v_attr FROM attribute_table...

Obviously you must declare v_attr as well...

Create multiple threads and wait all of them to complete

I've made a very simple extension method to wait for all threads of a collection:

using System.Collections.Generic;
using System.Threading;

namespace Extensions
{
    public static class ThreadExtension
    {
        public static void WaitAll(this IEnumerable<Thread> threads)
        {
            if(threads!=null)
            {
                foreach(Thread thread in threads)
                { thread.Join(); }
            }
        }
    }
}

Then you simply call:

List<Thread> threads=new List<Thread>();
// Add your threads to this collection
threads.WaitAll();

Serializing to JSON in jQuery

I did find this somewhere. Can't remember where though... probably on StackOverflow :)

$.fn.serializeObject = function(){
    var o = {};
    var a = this.serializeArray();
    $.each(a, function() {
        if (o[this.name]) {
            if (!o[this.name].push) {
                o[this.name] = [o[this.name]];
            }
            o[this.name].push(this.value || '');
        } else {
            o[this.name] = this.value || '';
        }
    });
    return o;
};

How to test enum types?

For enums, I test them only when they actually have methods in them. If it's a pure value-only enum like your example, I'd say don't bother.

But since you're keen on testing it, going with your second option is much better than the first. The problem with the first is that if you use an IDE, any renaming on the enums would also rename the ones in your test class.

How to exclude file only from root folder in Git

Older versions of git require you first define an ignore pattern and immediately (on the next line) define the exclusion. [tested on version 1.9.3 (Apple Git-50)]

/config.php
!/*/config.php

Later versions only require the following [tested on version 2.2.1]

/config.php

How can I extract the folder path from file path in Python?

You were almost there with your use of the split function. You just needed to join the strings, like follows.

>>> import os
>>> '\\'.join(existGDBPath.split('\\')[0:-1])
'T:\\Data\\DBDesign'

Although, I would recommend using the os.path.dirname function to do this, you just need to pass the string, and it'll do the work for you. Since, you seem to be on windows, consider using the abspath function too. An example:

>>> import os
>>> os.path.dirname(os.path.abspath(existGDBPath))
'T:\\Data\\DBDesign'

If you want both the file name and the directory path after being split, you can use the os.path.split function which returns a tuple, as follows.

>>> import os
>>> os.path.split(os.path.abspath(existGDBPath))
('T:\\Data\\DBDesign', 'DBDesign_93_v141b.mdb')

is not JSON serializable

It's worth noting that the QuerySet.values_list() method doesn't actually return a list, but an object of type django.db.models.query.ValuesListQuerySet, in order to maintain Django's goal of lazy evaluation, i.e. the DB query required to generate the 'list' isn't actually performed until the object is evaluated.

Somewhat irritatingly, though, this object has a custom __repr__ method which makes it look like a list when printed out, so it's not always obvious that the object isn't really a list.

The exception in the question is caused by the fact that custom objects cannot be serialized in JSON, so you'll have to convert it to a list first, with...

my_list = list(self.get_queryset().values_list('code', flat=True))

...then you can convert it to JSON with...

json_data = json.dumps(my_list)

You'll also have to place the resulting JSON data in an HttpResponse object, which, apparently, should have a Content-Type of application/json, with...

response = HttpResponse(json_data, content_type='application/json')

...which you can then return from your function.

Return value using String result=Command.ExecuteScalar() error occurs when result returns null

Use SQL server isnull function

public string absentDayNo(DateTime sdate, DateTime edate, string idemp)
{ 
    string result="0";
    string myQuery="select isnull(COUNT(idemp_atd),0) as absentDayNo from td_atd where ";
    myQuery +=" absentdate_atd between '"+sdate+"' and '"+edate+" ";
    myQuery +=" and idemp_atd='"+idemp+"' group by idemp_atd ";

    SqlCommand cmd = new SqlCommand(myQuery, conn);
    conn.Open();
    //System.NullReferenceException occurs when their is no data/result
    string getValue = cmd.ExecuteScalar().ToString();
    if (getValue != null)
    {
        result = getValue.ToString();
    }
    conn.Close();
    return result;
}

Alter column in SQL Server

To set a default value to a column, try this:

ALTER TABLE tb_TableName
ALTER COLUMN Record_Status SET DEFAULT 'default value'

Git : fatal: Could not read from remote repository. Please make sure you have the correct access rights and the repository exists

I asked in the discussion:

does ssh -T [email protected] ouput the same username (in Hi [My Username]!) as in the one used for the ssh url of your repo ([email protected]:username/repo.git)?

Sorry It not showing same name

That means somehow the credentials have changed.

One solution would be to at least copy %HOME%\.ssh\id_rsa.pub in the SSH keys section of the right GitHub account

The OP adds:

I am working on private repo. So In [email protected]:username/repo.git,

I replied:

If you were able to clone/push to that repo whose username is not your own GitHub account, that must be because you had your previous public ssh key added as a contributor to that repo by the repo's owner.

What next is to ask that same repo owner to add your current public ssh key %HOME%\.ssh\id_rsa.pub to the repo contributor list.
So check with the owner that you (meaning your public ssh key) are declared as a contributor.

Does hosts file exist on the iPhone? How to change it?

It might exist, but you cannot change it on a non-jailbreaked iPhone.

Assuming that your development webserver is on a Mac, why don't you simply use its Bonjour name (e.g. MyMac.local.) instead of myrealwebserverontheinternet.com?

Converting binary to decimal integer output

If you want/need to do it without int:

sum(int(c) * (2 ** i) for i, c in enumerate(s[::-1]))

This reverses the string (s[::-1]), gets each character c and its index i (for i, c in enumerate(), multiplies the integer of the character (int(c)) by two to the power of the index (2 ** i) then adds them all together (sum()).

How can I change the value of the elements in a vector?

You might want to consider using some algorithms instead:

// read in the data:
std::copy(std::istream_iterator<double>(input), 
          std::istream_iterator<double>(),
          std::back_inserter(v));

sum = std::accumulate(v.begin(), v.end(), 0);
average = sum / v.size();

You can modify the values with std::transform, though until we get lambda expressions (C++0x) it may be more trouble than it's worth:

class difference { 
    double base;
public:
    difference(double b) : base(b) {}
    double operator()(double v) { return v-base; }
};

std::transform(v.begin(), v.end(), v.begin(), difference(average));

MongoDB - Update objects in a document's array (nested updating)

For question #1, let's break it into two parts. First, increment any document that has "items.item_name" equal to "my_item_two". For this you'll have to use the positional "$" operator. Something like:

 db.bar.update( {user_id : 123456 , "items.item_name" : "my_item_two" } , 
                {$inc : {"items.$.price" : 1} } , 
                false , 
                true);

Note that this will only increment the first matched subdocument in any array (so if you have another document in the array with "item_name" equal to "my_item_two", it won't get incremented). But this might be what you want.

The second part is trickier. We can push a new item to an array without a "my_item_two" as follows:

 db.bar.update( {user_id : 123456, "items.item_name" : {$ne : "my_item_two" }} , 
                {$addToSet : {"items" : {'item_name' : "my_item_two" , 'price' : 1 }} } ,
                false , 
                true);

For your question #2, the answer is easier. To increment the total and the price of item_three in any document that contains "my_item_three," you can use the $inc operator on multiple fields at the same time. Something like:

db.bar.update( {"items.item_name" : {$ne : "my_item_three" }} ,
               {$inc : {total : 1 , "items.$.price" : 1}} ,
               false ,
               true);

Python date string to date object

you have a date string like this, "24052010" and you want date object for this,

from datetime import datetime
cus_date = datetime.strptime("24052010", "%d%m%Y").date()

this cus_date will give you date object.

you can retrieve date string from your date object using this,

cus_date.strftime("%d%m%Y")

PHP cURL HTTP PUT

In a POST method, you can put an array. However, in a PUT method, you should use http_build_query to build the params like this:

curl_setopt( $ch, CURLOPT_POSTFIELDS, http_build_query( $postArr ) );

Frequency table for a single variable

The answer provided by @DSM is simple and straightforward, but I thought I'd add my own input to this question. If you look at the code for pandas.value_counts, you'll see that there is a lot going on.

If you need to calculate the frequency of many series, this could take a while. A faster implementation would be to use numpy.unique with return_counts = True

Here is an example:

import pandas as pd
import numpy as np

my_series = pd.Series([1,2,2,3,3,3])

print(my_series.value_counts())
3    3
2    2
1    1
dtype: int64

Notice here that the item returned is a pandas.Series

In comparison, numpy.unique returns a tuple with two items, the unique values and the counts.

vals, counts = np.unique(my_series, return_counts=True)
print(vals, counts)
[1 2 3] [1 2 3]

You can then combine these into a dictionary:

results = dict(zip(vals, counts))
print(results)
{1: 1, 2: 2, 3: 3}

And then into a pandas.Series

print(pd.Series(results))
1    1
2    2
3    3
dtype: int64

Simplest way to form a union of two lists

If it is a list, you can also use AddRange method.

var listB = new List<int>{3, 4, 5};  
var listA = new List<int>{1, 2, 3, 4, 5};

listA.AddRange(listB); // listA now has elements of listB also.

If you need new list (and exclude the duplicate), you can use Union

  var listB = new List<int>{3, 4, 5};  
  var listA = new List<int>{1, 2, 3, 4, 5};
  var listFinal = listA.Union(listB);

If you need new list (and include the duplicate), you can use Concat

  var listB = new List<int>{3, 4, 5};  
  var listA = new List<int>{1, 2, 3, 4, 5};
  var listFinal = listA.Concat(listB);

If you need common items, you can use Intersect.

var listB = new List<int>{3, 4, 5};  
var listA = new List<int>{1, 2, 3, 4};  
var listFinal = listA.Intersect(listB); //3,4

Extract regression coefficient values

The package broom comes in handy here (it uses the "tidy" format).

tidy(mg) will give a nicely formated data.frame with coefficients, t statistics etc. Works also for other models (e.g. plm, ...).

Example from broom's github repo:

lmfit <- lm(mpg ~ wt, mtcars)
require(broom)    
tidy(lmfit)

      term estimate std.error statistic   p.value
1 (Intercept)   37.285   1.8776    19.858 8.242e-19
2          wt   -5.344   0.5591    -9.559 1.294e-10

is.data.frame(tidy(lmfit))
[1] TRUE

image size (drawable-hdpi/ldpi/mdpi/xhdpi)

low dpi is 0.75x dimensions of medium dpi

high dpi is 1.5x dimensions of medium dpi

extra high dpi is 2x dimensinons of medium dpi

It's a good practice to make all the images in vector based format so you can resize them easily using a vector design software like Illustrator etc..

List of strings to one string

String.Join() is implemented quite fast, and as you already have a collection of the strings in question, is probably the best choice. Above all, it shouts "I'm joining a list of strings!" Always nice.

How can I determine if a variable is 'undefined' or 'null'?

jQuery attr() function returns either a blank string or the actual value (and never null or undefined). The only time it returns undefined is when your selector didn't return any element.

So you may want to test against a blank string. Alternatively, since blank strings, null and undefined are false-y, you can just do this:

if (!EmpName) { //do something }

Logarithmic returns in pandas dataframe

The results might seem similar, but that is just because of the Taylor expansion for the logarithm. Since log(1 + x) ~ x, the results can be similar.

However,

I am using the following code to get logarithmic returns, but it gives the exact same values as the pct.change() function.

is not quite correct.

import pandas as pd

df = pd.DataFrame({'p': range(10)})

df['pct_change'] = df.pct_change()
df['log_stuff'] = \
    np.log(df['p'].astype('float64')/df['p'].astype('float64').shift(1))
df[['pct_change', 'log_stuff']].plot();

enter image description here

Multiple markers Google Map API v3 from array of addresses and avoid OVER_QUERY_LIMIT while geocoding on pageLoad

Here is my solution:

dependencies: Gmaps.js, jQuery

var Maps = function($) {
   var lost_addresses = [],
       geocode_count  = 0;

   var addMarker = function() { console.log('Marker Added!') };

   return {
     getGecodeFor: function(addresses) {
        var latlng;
        lost_addresses = [];
        for(i=0;i<addresses.length;i++) {
          GMaps.geocode({
            address: addresses[i],
            callback: function(response, status) {
              if(status == google.maps.GeocoderStatus.OK) {
                addMarker();
              } else if(status == google.maps.GeocoderStatus.OVER_QUERY_LIMIT) {
                lost_addresses.push(addresses[i]);
              }

               geocode_count++;
               // notify listeners when the geocode is done
               if(geocode_count == addresses.length) {
                 $.event.trigger({ type: 'done:geocoder' });
               }
            }
          });
        }
     },
     processLostAddresses: function() {
       if(lost_addresses.length > 0) {
         this.getGeocodeFor(lost_addresses);
       }
     }
   };
}(jQuery);

Maps.getGeocodeFor(address);

// listen to done:geocode event and process the lost addresses after 1.5s
$(document).on('done:geocode', function() {
  setTimeout(function() {
    Maps.processLostAddresses();
  }, 1500);
});

Transposing a 2D-array in JavaScript

I think this is slightly more readable. It uses Array.from and logic is identical to using nested loops:

_x000D_
_x000D_
var arr = [_x000D_
  [1, 2, 3, 4],_x000D_
  [1, 2, 3, 4],_x000D_
  [1, 2, 3, 4]_x000D_
];_x000D_
_x000D_
/*_x000D_
 * arr[0].length = 4 = number of result rows_x000D_
 * arr.length = 3 = number of result cols_x000D_
 */_x000D_
_x000D_
var result = Array.from({ length: arr[0].length }, function(x, row) {_x000D_
  return Array.from({ length: arr.length }, function(x, col) {_x000D_
    return arr[col][row];_x000D_
  });_x000D_
});_x000D_
_x000D_
console.log(result);
_x000D_
_x000D_
_x000D_

If you are dealing with arrays of unequal length you need to replace arr[0].length with something else:

_x000D_
_x000D_
var arr = [_x000D_
  [1, 2],_x000D_
  [1, 2, 3],_x000D_
  [1, 2, 3, 4]_x000D_
];_x000D_
_x000D_
/*_x000D_
 * arr[0].length = 4 = number of result rows_x000D_
 * arr.length = 3 = number of result cols_x000D_
 */_x000D_
_x000D_
var result = Array.from({ length: arr.reduce(function(max, item) { return item.length > max ? item.length : max; }, 0) }, function(x, row) {_x000D_
  return Array.from({ length: arr.length }, function(x, col) {_x000D_
    return arr[col][row];_x000D_
  });_x000D_
});_x000D_
_x000D_
console.log(result);
_x000D_
_x000D_
_x000D_

How to get overall CPU usage (e.g. 57%) on Linux

Take a look at cat /proc/stat

grep 'cpu ' /proc/stat | awk '{usage=($2+$4)*100/($2+$4+$5)} END {print usage "%"}'

EDIT please read comments before copy-paste this or using this for any serious work. This was not tested nor used, it's an idea for people who do not want to install a utility or for something that works in any distribution. Some people think you can "apt-get install" anything.

NOTE: this is not the current CPU usage, but the overall CPU usage in all the cores since the system bootup. This could be very different from the current CPU usage. To get the current value top (or similar tool) must be used.

Current CPU usage can be potentially calculated with:

awk '{u=$2+$4; t=$2+$4+$5; if (NR==1){u1=u; t1=t;} else print ($2+$4-u1) * 100 / (t-t1) "%"; }' \
<(grep 'cpu ' /proc/stat) <(sleep 1;grep 'cpu ' /proc/stat)

How do I see which checkbox is checked?

If the checkbox is checked, then the checkbox's value will be passed. Otherwise, the field is not passed in the HTTP post.

if (isset($_POST['mycheckbox'])) {
    echo "checked!";
}

Run Jquery function on window events: load, resize, and scroll?

just call your function inside the events.

load:

$(document).ready(function(){  // or  $(window).load(function(){
    topInViewport($(mydivname));
});

resize:

$(window).resize(function () {
    topInViewport($(mydivname));
});

scroll:

$(window).scroll(function () {
    topInViewport($(mydivname));
});

or bind all event in one function

$(window).on("load scroll resize",function(e){

Passing parameter using onclick or a click binding with KnockoutJS

I know this is an old question, but here is my contribution. Instead of all these tricks, you can just simply wrap a function inside another function. Like I have done here:

<div data-bind="click: function(){ f('hello parameter'); }">Click me once</div>
<div data-bind="click: function(){ f('no no parameter'); }">Click me twice</div>

var VM = function(){
   this.f = function(param){
     console.log(param);
   }
}
ko.applyBindings(new VM());

And here is the fiddle

IF a == true OR b == true statement

Comparison expressions should each be in their own brackets:

{% if (a == 'foo') or (b == 'bar') %}
    ...
{% endif %}

Alternative if you are inspecting a single variable and a number of possible values:

{% if a in ['foo', 'bar', 'qux'] %}
    ...
{% endif %}

Select All Rows Using Entity Framework

How about:

using (ModelName context = new ModelName())
{
    var ptx = (from r in context.TableName select r);
}

ModelName is the class auto-generated by the designer, which inherits from ObjectContext.

Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?

Indeed an implementation fault.

The native approach in MySQL is to update a creation date yourself ( if you need one ) and have MySQL worry about the timestamp update date ? update date : creation date like so:

CREATE TABLE tracked_data( 
  `data` TEXT,
  `timestamp`   TIMESTAMP,
  `creation_date` TIMESTAMP                                   
) ENGINE=INNODB; 

On creation Insert NULL:

INSERT INTO tracked_data(`data`,`creation_date`) VALUES ('creation..',NULL);

NULL values for timestamp are interperted as CURRENT_TIMESTAMP by default.

In MySQL the first TIMESTAMP column of a table gets both DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP attribute, if no attributes are given for it. this is why TIMESTAMP column with attributes must come first or you get the error described in this thread.

The specified child already has a parent. You must call removeView() on the child's parent first (Android)

In my case, I was doing this (wrong):

...
TextView content = new TextView(context);
for (Quote quote : favQuotes) {
  content.setText(quote.content);
...

instead of (good):

...
for (Quote quote : favQuotes) {
  TextView content = new TextView(context);
  content.setText(quote.content);
...

Unable to find the requested .Net Framework Data Provider in Visual Studio 2010 Professional

I like the other suggestions but I would rather not update the machine.config for a single application. I suggest that you just add it to the web.config / app.config. Here is what I needed to use the MySql Connector/NET that I "bin" deployed.

<system.data>
    <DbProviderFactories >
        <add name="MySQL Data Provider" invariant="MySql.Data.MySqlClient" description=".Net Framework Data Provider for MySQL" type="MySql.Data.MySqlClient.MySqlClientFactory, MySql.Data, Version=6.6.4.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" />
    </DbProviderFactories>
</system.data>

Span inside anchor or anchor inside span or doesn't matter?

Semantically I think makes more sense as is a container for a single element and if you need to nest them then that suggests more than element will be inside of the outer one.

C# how to wait for a webpage to finish loading before continuing

Try the DocumentCompleted Event

webBrowser.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser_DocumentCompleted);

void webBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
    webBrowser.Document.GetElementById("product").SetAttribute("value", product);
    webBrowser.Document.GetElementById("version").SetAttribute("value", version);
    webBrowser.Document.GetElementById("commit").InvokeMember("click");
}

GCC C++ Linker errors: Undefined reference to 'vtable for XXX', Undefined reference to 'ClassName::ClassName()'

If you have a base class with pure virtual function, make sure your base class constructor and destructor has body otherwise linker fails.

Tuples( or arrays ) as Dictionary keys in C#

If for some reason you really want to avoid creating your own Tuple class, or using on built into .NET 4.0, there is one other approach possible; you can combine the three key values together into a single value.

For example, if the three values are integer types together not taking more than 64 bits, you could combine them into a ulong.

Worst-case you can always use a string, as long as you make sure the three components in it are delimited with some character or sequence that does not occur inside the components of the key, for example, with three numbers you could try:

string.Format("{0}#{1}#{2}", key1, key2, key3)

There is obviously some composition overhead in this approach, but depending on what you are using it for this may be trivial enough not to care about it.

Python division

In Python 2.7, the / operator is an integer division if inputs are integers:

>>>20/15
1

>>>20.0/15.0
1.33333333333

>>>20.0/15
1.33333333333

In Python 3.3, the / operator is a float division even if the inputs are integer.

>>> 20/15
1.33333333333

>>>20.0/15
1.33333333333

For integer division in Python 3, we will use the // operator.

The // operator is an integer division operator in both Python 2.7 and Python 3.3.

In Python 2.7 and Python 3.3:

>>>20//15
1

Now, see the comparison

>>>a = 7.0/4.0
>>>b = 7/4
>>>print a == b

For the above program, the output will be False in Python 2.7 and True in Python 3.3.

In Python 2.7 a = 1.75 and b = 1.

In Python 3.3 a = 1.75 and b = 1.75, just because / is a float division.

How to read XML response from a URL in java?

Get your response via a regular http-request, using:

The next step is parsing it. Take a look at this article for a choice of parser.

How can I change the app display name build with Flutter?

First Rename your AndroidManifest.xml file

android:label="Your App Name"

Second Rename Your Application Name in Pubspec.yaml file name: Your Application Name

Third Change Your Application logo

flutter_icons:
   android: "launcher_icon"
   ios: true
   image_path: "assets/path/your Application logo.formate"

Fourth Run

flutter pub pub run flutter_launcher_icons:main

Importing Excel spreadsheet data into another Excel spreadsheet containing VBA

Data can be pulled into an excel from another excel through Workbook method or External reference or through Data Import facility.

If you want to read or even if you want to update another excel workbook, these methods can be used. We may not depend only on VBA for this.

For more info on these techniques, please click here to refer the article

How to convert Moment.js date to users local timezone?

You do not need to use moment-timezone for this. The main moment.js library has full functionality for working with UTC and the local time zone.

var testDateUtc = moment.utc("2015-01-30 10:00:00");
var localDate = moment(testDateUtc).local();

From there you can use any of the functions you might expect:

var s = localDate.format("YYYY-MM-DD HH:mm:ss");
var d = localDate.toDate();
// etc...

Note that by passing testDateUtc, which is a moment object, back into the moment() constructor, it creates a clone. Otherwise, when you called .local(), it would also change the testDateUtc value, instead of just the localDate value. Moments are mutable.

Also note that if your original input contains a time zone offset such as +00:00 or Z, then you can just parse it directly with moment. You don't need to use .utc or .local. For example:

var localDate = moment("2015-01-30T10:00:00Z");

Multiprocessing vs Threading Python

Threading's job is to enable applications to be responsive. Suppose you have a database connection and you need to respond to user input. Without threading, if the database connection is busy the application will not be able to respond to the user. By splitting off the database connection into a separate thread you can make the application more responsive. Also because both threads are in the same process, they can access the same data structures - good performance, plus a flexible software design.

Note that due to the GIL the app isn't actually doing two things at once, but what we've done is put the resource lock on the database into a separate thread so that CPU time can be switched between it and the user interaction. CPU time gets rationed out between the threads.

Multiprocessing is for times when you really do want more than one thing to be done at any given time. Suppose your application needs to connect to 6 databases and perform a complex matrix transformation on each dataset. Putting each job in a separate thread might help a little because when one connection is idle another one could get some CPU time, but the processing would not be done in parallel because the GIL means that you're only ever using the resources of one CPU. By putting each job in a Multiprocessing process, each can run on it's own CPU and run at full efficiency.

Checking for the correct number of arguments

You can check the total number of arguments which are passed in command line with "$#" Say for Example my shell script name is hello.sh

sh hello.sh hello-world
# I am passing hello-world as argument in command line which will b considered as 1 argument 
if [ $# -eq 1 ] 
then
    echo $1
else
    echo "invalid argument please pass only one argument "
fi

Output will be hello-world

What characters are forbidden in Windows and Linux directory names?

For Windows you can check it using PowerShell

$PathInvalidChars = [System.IO.Path]::GetInvalidPathChars() #36 chars

To display UTF-8 codes you can convert

$enc = [system.Text.Encoding]::UTF8
$PathInvalidChars | foreach { $enc.GetBytes($_) }

$FileNameInvalidChars = [System.IO.Path]::GetInvalidFileNameChars() #41 chars

$FileOnlyInvalidChars = @(':', '*', '?', '\', '/') #5 chars - as a difference

C++ Array Of Pointers

I would do it something along these lines:

class Foo{
...
};

int main(){
  Foo* arrayOfFoo[100]; //[1]

  arrayOfFoo[0] = new Foo; //[2]
}

[1] This makes an array of 100 pointers to Foo-objects. But no Foo-objects are actually created.

[2] This is one possible way to instantiate an object, and at the same time save a pointer to this object in the first position of your array.

Apache HttpClient Interim Error: NoHttpResponseException

Solution: change the ReuseStrategy to never

Since this problem is very complex and there are so many different factors which can fail I was happy to find this solution in another post: How to solve org.apache.http.NoHttpResponseException

Never reuse connections: configure in org.apache.http.impl.client.AbstractHttpClient:

httpClient.setReuseStrategy(new NoConnectionReuseStrategy());

The same can be configured on a org.apache.http.impl.client.HttpClientBuilder builder:

builder.setConnectionReuseStrategy(new NoConnectionReuseStrategy());

JS Client-Side Exif Orientation: Rotate and Mirror JPEG Images

I am using mixed solution (php+css).

Containers are needed for:

  • div.imgCont2 container needed to rotate;
  • div.imgCont1 container needed to zoomOut - width:150%;
  • div.imgCont container needed for scrollbars, when image is zoomOut.

.

<?php
    $image_url = 'your image url.jpg';
    $exif = @exif_read_data($image_url,0,true);
    $orientation = @$exif['IFD0']['Orientation'];
?>

<style>
.imgCont{
    width:100%;
    overflow:auto;
}
.imgCont2[data-orientation="8"]{
    transform:rotate(270deg);
    margin:15% 0;
}
.imgCont2[data-orientation="6"]{
    transform:rotate(90deg);
    margin:15% 0;
}
.imgCont2[data-orientation="3"]{
    transform:rotate(180deg);
}
img{
    width:100%;
}
</style>

<div class="imgCont">
  <div class="imgCont1">
    <div class="imgCont2" data-orientation="<?php echo($orientation) ?>">
      <img src="<?php echo($image_url) ?>">
    </div>
  </div>
</div>

How can I find out a file's MIME type (Content-Type)?

Use file. Examples:

> file --mime-type image.png
image.png: image/png

> file -b --mime-type image.png
image/png

> file -i FILE_NAME
image.png: image/png; charset=binary

Check if an element is present in an array

You can use indexOf But not working well in the last version of internet explorer. Code:

function isInArray(value, array) {
  return array.indexOf(value) > -1;
}

Execution:

isInArray(1, [1,2,3]); // true

I suggest you use the following code:

function inArray(needle, haystack) {
 var length = haystack.length;
 for (var i = 0; i < length; i++) {
 if (haystack[i] == needle)
  return true;
 }
 return false;
}

How to convert an iterator to a stream?

Another way to do this on Java 9+ using Stream::iterate(T, Predicate, UnaryOperator):

Stream.iterate(iterator, Iterator::hasNext, UnaryOperator.identity())
        .map(Iterator::next)
        .forEach(System.out::println);

How do I get the picture size with PIL?

Here's how you get the image size from the given URL in Python 3:

from PIL import Image
import urllib.request
from io import BytesIO

file = BytesIO(urllib.request.urlopen('http://getwallpapers.com/wallpaper/full/b/8/d/32803.jpg').read())
im = Image.open(file)
width, height = im.size

How does Trello access the user's clipboard?

Disclosure: I wrote the code that Trello uses; the code below is the actual source code Trello uses to accomplish the clipboard trick.


We don't actually "access the user's clipboard", instead we help the user out a bit by selecting something useful when they press Ctrl+C.

Sounds like you've figured it out; we take advantage of the fact that when you want to hit Ctrl+C, you have to hit the Ctrl key first. When the Ctrl key is pressed, we pop in a textarea that contains the text we want to end up on the clipboard, and select all the text in it, so the selection is all set when the C key is hit. (Then we hide the textarea when the Ctrl key comes up.)

Specifically, Trello does this:

TrelloClipboard = new class
  constructor: ->
    @value = ""

    $(document).keydown (e) =>
      # Only do this if there's something to be put on the clipboard, and it
      # looks like they're starting a copy shortcut
      if !@value || !(e.ctrlKey || e.metaKey)
        return

      if $(e.target).is("input:visible,textarea:visible")
        return

      # Abort if it looks like they've selected some text (maybe they're trying
      # to copy out a bit of the description or something)
      if window.getSelection?()?.toString()
        return

      if document.selection?.createRange().text
        return

      _.defer =>
        $clipboardContainer = $("#clipboard-container")
        $clipboardContainer.empty().show()
        $("<textarea id='clipboard'></textarea>")
        .val(@value)
        .appendTo($clipboardContainer)
        .focus()
        .select()

    $(document).keyup (e) ->
      if $(e.target).is("#clipboard")
        $("#clipboard-container").empty().hide()

  set: (@value) ->

In the DOM we've got:

<div id="clipboard-container"><textarea id="clipboard"></textarea></div>

CSS for the clipboard stuff:

#clipboard-container {
  position: fixed;
  left: 0px;
  top: 0px;
  width: 0px;
  height: 0px;
  z-index: 100;
  display: none;
  opacity: 0;
}
#clipboard {
  width: 1px;
  height: 1px;
  padding: 0px;
}

... and the CSS makes it so you can't actually see the textarea when it pops in ... but it's "visible" enough to copy from.

When you hover over a card, it calls

TrelloClipboard.set(cardUrl)

... so then the clipboard helper knows what to select when the Ctrl key is pressed.

How to redirect stderr and stdout to different files in the same line in script?

Or if you like to mix outputs (stdout & stderr) in one single file you may want to use:

command > merged-output.txt 2>&1

configure Git to accept a particular self-signed server certificate for a particular https remote

On windows in a corporate environment where certificates are distributed from a single source, I found this answer solved the issue: https://stackoverflow.com/a/48212753/761755

How to make a DIV always float on the screen in top right corner?

Use position: fixed, and anchor it to the top and right sides of the page:

#fixed-div {
    position: fixed;
    top: 1em;
    right: 1em;
}

IE6 does not support position: fixed, however. If you need this functionality in IE6, this purely-CSS solution seems to do the trick. You'll need a wrapper <div> to contain some of the styles for it to work, as seen in the stylesheet.

KERNELBASE.dll Exception 0xe0434352 offset 0x000000000000a49d

0xe0434352 is the SEH code for a CLR exception. If you don't understand what that means, stop and read A Crash Course on the Depths of Win32™ Structured Exception Handling. So your process is not handling a CLR exception. Don't shoot the messenger, KERNELBASE.DLL is just the unfortunate victim. The perpetrator is MyApp.exe.

There should be a minidump of the crash in DrWatson folders with a full stack, it will contain everything you need to root cause the issue.

I suggest you wire up, in your myapp.exe code, AppDomain.UnhandledException and Application.ThreadException, as appropriate.

Direct casting vs 'as' operator?

It seems the two of them are conceptually different.

Direct Casting

Types don't have to be strictly related. It comes in all types of flavors.

  • Custom implicit/explicit casting: Usually a new object is created.
  • Value Type Implicit: Copy without losing information.
  • Value Type Explicit: Copy and information might be lost.
  • IS-A relationship: Change reference type, otherwise throws exception.
  • Same type: 'Casting is redundant'.

It feels like the object is going to be converted into something else.

AS operator

Types have a direct relationship. As in:

  • Reference Types: IS-A relationship Objects are always the same, just the reference changes.
  • Value Types: Copy boxing and nullable types.

It feels like the you are going to handle the object in a different way.

Samples and IL

    class TypeA
    {
        public int value;
    }

    class TypeB
    {
        public int number;

        public static explicit operator TypeB(TypeA v)
        {
            return new TypeB() { number = v.value };
        }
    }

    class TypeC : TypeB { }
    interface IFoo { }
    class TypeD : TypeA, IFoo { }

    void Run()
    {
        TypeA customTypeA = new TypeD() { value = 10 };
        long longValue = long.MaxValue;
        int intValue = int.MaxValue;

        // Casting 
        TypeB typeB = (TypeB)customTypeA; // custom explicit casting -- IL:  call class ConsoleApp1.Program/TypeB ConsoleApp1.Program/TypeB::op_Explicit(class ConsoleApp1.Program/TypeA)
        IFoo foo = (IFoo)customTypeA; // is-a reference -- IL: castclass  ConsoleApp1.Program/IFoo

        int loseValue = (int)longValue; // explicit -- IL: conv.i4
        long dontLose = intValue; // implict -- IL: conv.i8

        // AS 
        int? wraps = intValue as int?; // nullable wrapper -- IL:  call instance void valuetype [System.Runtime]System.Nullable`1<int32>::.ctor(!0)
        object o1 = intValue as object; // box -- IL: box [System.Runtime]System.Int32
        TypeD d1 = customTypeA as TypeD; // reference conversion -- IL: isinst ConsoleApp1.Program/TypeD
        IFoo f1 = customTypeA as IFoo; // reference conversion -- IL: isinst ConsoleApp1.Program/IFoo

        //TypeC d = customTypeA as TypeC; // wouldn't compile
    }

How does python numpy.where() work?

How do they achieve internally that you are able to pass something like x > 5 into a method?

The short answer is that they don't.

Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolean arrays where the given condition is true).

E.g.

x = np.arange(9).reshape(3,3)
print x > 5

yields:

array([[False, False, False],
       [False, False, False],
       [ True,  True,  True]], dtype=bool)

This is the same reason why something like if x > 5: raises a ValueError if x is a numpy array. It's an array of True/False values, not a single value.

Furthermore, numpy arrays can be indexed by boolean arrays. E.g. x[x>5] yields [6 7 8], in this case.

Honestly, it's fairly rare that you actually need numpy.where but it just returns the indicies where a boolean array is True. Usually you can do what you need with simple boolean indexing.

Can I compile all .cpp files in src/ to .o's in obj/, then link to binary in ./?

Makefile part of the question

This is pretty easy, unless you don't need to generalize try something like the code below (but replace space indentation with tabs near g++)

SRC_DIR := .../src
OBJ_DIR := .../obj
SRC_FILES := $(wildcard $(SRC_DIR)/*.cpp)
OBJ_FILES := $(patsubst $(SRC_DIR)/%.cpp,$(OBJ_DIR)/%.o,$(SRC_FILES))
LDFLAGS := ...
CPPFLAGS := ...
CXXFLAGS := ...

main.exe: $(OBJ_FILES)
   g++ $(LDFLAGS) -o $@ $^

$(OBJ_DIR)/%.o: $(SRC_DIR)/%.cpp
   g++ $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $<

Automatic dependency graph generation

A "must" feature for most make systems. With GCC in can be done in a single pass as a side effect of the compilation by adding -MMD flag to CXXFLAGS and -include $(OBJ_FILES:.o=.d) to the end of the makefile body:

CXXFLAGS += -MMD
-include $(OBJ_FILES:.o=.d)

And as guys mentioned already, always have GNU Make Manual around, it is very helpful.

Recommendation for compressing JPG files with ImageMagick

Once I needed to resize photos from camera for developing:

  • Original filesize: 2800 kB
  • Resolution: 3264x2448

Command:

mogrify -quality "97%" -resize 2048x2048 -filter Lanczos -interlace Plane -gaussian-blur 0.05 
  • Result filesize 753 kB
  • Resolution 2048x2048

and I can't see any changes in full screen with my 1920x1080 resolution monitor. 2048 resolution is the best for developing 10 cm photos at maximum quality of 360 dpi. I don't want to strip it.

edit: I noticed that I even get much better results without blurring. Without blurring filesize is 50% of original, but quality is better (when zooming).

Is there a math nCr function in python?

Do you want iteration? itertools.combinations. Common usage:

>>> import itertools
>>> itertools.combinations('abcd',2)
<itertools.combinations object at 0x01348F30>
>>> list(itertools.combinations('abcd',2))
[('a', 'b'), ('a', 'c'), ('a', 'd'), ('b', 'c'), ('b', 'd'), ('c', 'd')]
>>> [''.join(x) for x in itertools.combinations('abcd',2)]
['ab', 'ac', 'ad', 'bc', 'bd', 'cd']

If you just need to compute the formula, use math.factorial:

import math

def nCr(n,r):
    f = math.factorial
    return f(n) / f(r) / f(n-r)

if __name__ == '__main__':
    print nCr(4,2)

In Python 3, use the integer division // instead of / to avoid overflows:

return f(n) // f(r) // f(n-r)

Output

6

How to get post slug from post in WordPress?

Here is most advanced and updated version what cover many cases:

if(!function_exists('the_slug')):
    function the_slug($post_id=false, $echo=true) {
        global $product, $page;

        if(is_numeric($post_id) && $post_id == intval($post_id)) {} else {
            if(!is_object($post_id)){}else if(property_exists($post_id, 'ID')){
                $post_id = $post_id->ID;
            }
            if(empty($post_id) && property_exists($product, 'ID')) $post_id = $product->ID;
            if(empty($post_id)) $post_id =  get_the_ID();

            if(empty($post_id) && property_exists($page, 'ID')) $post_id =  $page->ID;
        }

        if(!empty($post_id))
            $slug = basename(get_permalink($post_id));
        else
            $slug = basename(get_permalink());
        do_action('before_slug', $slug);
        $slug = apply_filters('slug_filter', $slug);
        if( $echo ) echo $slug;
        do_action('after_slug', $slug);
        return $slug;
      }
endif;

This is collections from the best answers and few my updates.

Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost."

We had this exact error and it turned out to be an issue with the underlying HTTP implementation of NSURLRequest:

As far as we can tell, when iOS 8/9/10/11 receive an HTTP response with a Keep-Alive header, it keeps this connection to re-use later (as it should), but it keeps it for more than the timeout parameter of the Keep-Alive header (it seems to always keep the connection alive for 30 seconds.) Then when a second request is sent by the app less than 30 seconds later, it tries to re-use a connection that might have been dropped by the server (if more than the real Keep-Alive has elapsed).

Here are the solutions we have found so far:

  • Increase the timeout parameter of the server above 30 seconds. It looks like iOS is always behaving as if the server will keep the connection open for 30 seconds regardless of the value provided in the Keep-Alive header. (This can be done for Apache by setting the KeepAliveTimeout option.
  • You can simply disable the keep alive mechanism for iOS clients based on the User-Agent of your app (e.g. for Apache: BrowserMatch "iOS 8\." nokeepalive in the mod file setenvif.conf)
  • If you don't have access to the server, you can try sending your requests with a Connection: close header: this will tell the server to drop the connection immediately and to respond without any keep alive headers. BUT at the moment, NSURLSession seems to override the Connection header when the requests are sent (we didn't test this solution extensively as we can tweak the Apache configuration)

Definition of "downstream" and "upstream"

Upstream (as related to) Tracking

The term upstream also has some unambiguous meaning as comes to the suite of GIT tools, especially relative to tracking

For example :

   $git rev-list --count --left-right "@{upstream}"...HEAD
   >4   12

will print (the last cached value of) the number of commits behind (left) and ahead (right) of your current working branch, relative to the (if any) currently tracking remote branch for this local branch. It will print an error message otherwise:

    >error: No upstream branch found for ''
  • As has already been said, you may have any number of remotes for one local repository, for example, if you fork a repository from github, then issue a 'pull request', you most certainly have at least two: origin (your forked repo on github) and upstream (the repo on github you forked from). Those are just interchangeable names, only the 'git@...' url identifies them.

Your .git/configreads :

   [remote "origin"]
       fetch = +refs/heads/*:refs/remotes/origin/*
       url = [email protected]:myusername/reponame.git
   [remote "upstream"]
       fetch = +refs/heads/*:refs/remotes/upstream/*
       url = [email protected]:authorname/reponame.git
  • On the other hand, @{upstream}'s meaning for GIT is unique :

it is 'the branch' (if any) on 'said remote', which is tracking the 'current branch' on your 'local repository'.

It's the branch you fetch/pull from whenever you issue a plain git fetch/git pull, without arguments.

Let's say want to set the remote branch origin/master to be the tracking branch for the local master branch you've checked out. Just issue :

   $ git branch --set-upstream  master origin/master
   > Branch master set up to track remote branch master from origin.

This adds 2 parameters in .git/config :

   [branch "master"]
       remote = origin
       merge = refs/heads/master

now try (provided 'upstream' remote has a 'dev' branch)

   $ git branch --set-upstream  master upstream/dev
   > Branch master set up to track remote branch dev from upstream.

.git/config now reads:

   [branch "master"]
       remote = upstream
       merge = refs/heads/dev

git-push(1) Manual Page :

   -u
   --set-upstream

For every branch that is up to date or successfully pushed, add upstream (tracking) reference, used by argument-less git-pull(1) and other commands. For more information, see branch.<name>.merge in git-config(1).

git-config(1) Manual Page :

   branch.<name>.merge

Defines, together with branch.<name>.remote, the upstream branch for the given branch. It tells git fetch/git pull/git rebase which branch to merge and can also affect git push (see push.default). \ (...)

   branch.<name>.remote

When in branch < name >, it tells git fetch and git push which remote to fetch from/push to. It defaults to origin if no remote is configured. origin is also used if you are not on any branch.

Upstream and Push (Gotcha)

take a look at git-config(1) Manual Page

   git config --global push.default upstream
   git config --global push.default tracking  (deprecated)

This is to prevent accidental pushes to branches which you’re not ready to push yet.

Position Absolute + Scrolling

I ran into this situation and creating an extra div was impractical. I ended up just setting the full-height div to height: 10000%; overflow: hidden;

Clearly not the cleanest solution, but it works really fast.

How to make a button redirect to another page using jQuery or just Javascript

No need for javascript, just wrap it in a link

<a href="http://www.google.com"><button type="button">button</button></a>

What does the explicit keyword mean?

The compiler is allowed to make one implicit conversion to resolve the parameters to a function. What this means is that the compiler can use constructors callable with a single parameter to convert from one type to another in order to get the right type for a parameter.

Here's an example class with a constructor that can be used for implicit conversions:

class Foo
{
public:
  // single parameter constructor, can be used as an implicit conversion
  Foo (int foo) : m_foo (foo) 
  {
  }

  int GetFoo () { return m_foo; }

private:
  int m_foo;
};

Here's a simple function that takes a Foo object:

void DoBar (Foo foo)
{
  int i = foo.GetFoo ();
}

and here's where the DoBar function is called:

int main ()
{
  DoBar (42);
}

The argument is not a Foo object, but an int. However, there exists a constructor for Foo that takes an int so this constructor can be used to convert the parameter to the correct type.

The compiler is allowed to do this once for each parameter.

Prefixing the explicit keyword to the constructor prevents the compiler from using that constructor for implicit conversions. Adding it to the above class will create a compiler error at the function call DoBar (42). It is now necessary to call for conversion explicitly with DoBar (Foo (42))

The reason you might want to do this is to avoid accidental construction that can hide bugs.
Contrived example:

  • You have a MyString(int size) class with a constructor that constructs a string of the given size. You have a function print(const MyString&), and you call print(3) (when you actually intended to call print("3")). You expect it to print "3", but it prints an empty string of length 3 instead.

UTF-8 output from PowerShell

This is a bug in .NET. When PowerShell launches, it caches the output handle (Console.Out). The Encoding property of that text writer does not pick up the value StandardOutputEncoding property.

When you change it from within PowerShell, the Encoding property of the cached output writer returns the cached value, so the output is still encoded with the default encoding.

As a workaround, I would suggest not changing the encoding. It will be returned to you as a Unicode string, at which point you can manage the encoding yourself.

Caching example:

102 [C:\Users\leeholm]
>> $r1 = [Console]::Out

103 [C:\Users\leeholm]
>> $r1

Encoding                                          FormatProvider
--------                                          --------------
System.Text.SBCSCodePageEncoding                  en-US



104 [C:\Users\leeholm]
>> [Console]::OutputEncoding = [System.Text.Encoding]::UTF8

105 [C:\Users\leeholm]
>> $r1

Encoding                                          FormatProvider
--------                                          --------------
System.Text.SBCSCodePageEncoding                  en-US

Taskkill /f doesn't kill a process

I could solve my issue rearding this problem by killing explorer.exe which in turn was addicted to the process I wanted to kill. I guess this may also happen if processes open interfaces via hook which may be locked.

The target ... overrides the `OTHER_LDFLAGS` build setting defined in `Pods/Pods.xcconfig

For me the problem was with my targets tests. I already had the $(inherited) flag in my main app target.

I added it to MyAppTests Other Linker flags. After that when I ran pod install the warning message was gone. enter image description here

Reset local repository branch to be just like remote repository HEAD

All of the above suggests are right, but often to really reset your project, you also need to remove even files that are in your .gitignore.

To get the moral equivalent of erasing your project directory and re-cloning from the remote is:

git fetch
git reset --hard
git clean -x -d -f

Warning: git clean -x -d -f is irreversible and you may lose files and data (e.g. things you have ignored using .gitignore).

Algorithm to calculate the number of divisors of a given number

Dmitriy is right that you'll want the Sieve of Atkin to generate the prime list but I don't believe that takes care of the whole issue. Now that you have a list of primes you'll need to see how many of those primes act as a divisor (and how often).

Here's some python for the algo Look here and search for "Subject: math - need divisors algorithm". Just count the number of items in the list instead of returning them however.

Here's a Dr. Math that explains what exactly it is you need to do mathematically.

Essentially it boils down to if your number n is:
n = a^x * b^y * c^z
(where a, b, and c are n's prime divisors and x, y, and z are the number of times that divisor is repeated) then the total count for all of the divisors is:
(x + 1) * (y + 1) * (z + 1).

Edit: BTW, to find a,b,c,etc you'll want to do what amounts to a greedy algo if I'm understanding this correctly. Start with your largest prime divisor and multiply it by itself until a further multiplication would exceed the number n. Then move to the next lowest factor and times the previous prime ^ number of times it was multiplied by the current prime and keep multiplying by the prime until the next will exceed n... etc. Keep track of the number of times you multiply the divisors together and apply those numbers into the formula above.

Not 100% sure about my algo description but if that isn't it it's something similar .

plot legends without border and with white background

As documented in ?legend you do this like so:

plot(1:10,type = "n")
abline(v=seq(1,10,1), col='grey', lty='dotted')
legend(1, 5, "This legend text should not be disturbed by the dotted grey lines,\nbut the plotted dots should still be visible",box.lwd = 0,box.col = "white",bg = "white")
points(1:10,1:10)

enter image description here

Line breaks are achieved with the new line character \n. Making the points still visible is done simply by changing the order of plotting. Remember that plotting in R is like drawing on a piece of paper: each thing you plot will be placed on top of whatever's currently there.

Note that the legend text is cut off because I made the plot dimensions smaller (windows.options does not exist on all R platforms).

Parse (split) a string in C++ using string delimiter (standard C++)

For string delimiter

Split string based on a string delimiter. Such as splitting string "adsf-+qwret-+nvfkbdsj-+orthdfjgh-+dfjrleih" based on string delimiter "-+", output will be {"adsf", "qwret", "nvfkbdsj", "orthdfjgh", "dfjrleih"}

#include <iostream>
#include <sstream>
#include <vector>

using namespace std;

// for string delimiter
vector<string> split (string s, string delimiter) {
    size_t pos_start = 0, pos_end, delim_len = delimiter.length();
    string token;
    vector<string> res;

    while ((pos_end = s.find (delimiter, pos_start)) != string::npos) {
        token = s.substr (pos_start, pos_end - pos_start);
        pos_start = pos_end + delim_len;
        res.push_back (token);
    }

    res.push_back (s.substr (pos_start));
    return res;
}

int main() {
    string str = "adsf-+qwret-+nvfkbdsj-+orthdfjgh-+dfjrleih";
    string delimiter = "-+";
    vector<string> v = split (str, delimiter);

    for (auto i : v) cout << i << endl;

    return 0;
}


Output

adsf
qwret
nvfkbdsj
orthdfjgh
dfjrleih




For single character delimiter

Split string based on a character delimiter. Such as splitting string "adsf+qwer+poui+fdgh" with delimiter "+" will output {"adsf", "qwer", "poui", "fdg"h}

#include <iostream>
#include <sstream>
#include <vector>

using namespace std;

vector<string> split (const string &s, char delim) {
    vector<string> result;
    stringstream ss (s);
    string item;

    while (getline (ss, item, delim)) {
        result.push_back (item);
    }

    return result;
}

int main() {
    string str = "adsf+qwer+poui+fdgh";
    vector<string> v = split (str, '+');

    for (auto i : v) cout << i << endl;

    return 0;
}


Output

adsf
qwer
poui
fdgh

Converting String Array to an Integer Array

Java has a method for this, "convertStringArrayToIntArray".

String numbers = sc.nextLine();
int[] intArray = convertStringArrayToIntArray(numbers.split(", "));

How do I clear the dropdownlist values on button click event using jQuery?

A shorter alternative to the first solution given by Russ Cam would be:

$('#mySelect').val('');

This assumes you want to retain the list, but make it so that no option is selected.

If you wish to select a particular default value, just pass that value instead of an empty string.

$('#mySelect').val('someDefaultValue');

or to do it by the index of the option, you could do:

$('#mySelect option:eq(0)').attr('selected','selected'); // Select first option

Python: slicing a multi-dimensional array

If you use numpy, this is easy:

slice = arr[:2,:2]

or if you want the 0's,

slice = arr[0:2,0:2]

You'll get the same result.

*note that slice is actually the name of a builtin-type. Generally, I would advise giving your object a different "name".


Another way, if you're working with lists of lists*:

slice = [arr[i][0:2] for i in range(0,2)]

(Note that the 0's here are unnecessary: [arr[i][:2] for i in range(2)] would also work.).

What I did here is that I take each desired row 1 at a time (arr[i]). I then slice the columns I want out of that row and add it to the list that I'm building.

If you naively try: arr[0:2] You get the first 2 rows which if you then slice again arr[0:2][0:2], you're just slicing the first two rows over again.

*This actually works for numpy arrays too, but it will be slow compared to the "native" solution I posted above.

pod has unbound PersistentVolumeClaims

You have to define a PersistentVolume providing disc space to be consumed by the PersistentVolumeClaim.

When using storageClass Kubernetes is going to enable "Dynamic Volume Provisioning" which is not working with the local file system.


To solve your issue:

  • Provide a PersistentVolume fulfilling the constraints of the claim (a size >= 100Mi)
  • Remove the storageClass-line from the PersistentVolumeClaim
  • Remove the StorageClass from your cluster

How do these pieces play together?

At creation of the deployment state-description it is usually known which kind (amount, speed, ...) of storage that application will need.
To make a deployment versatile you'd like to avoid a hard dependency on storage. Kubernetes' volume-abstraction allows you to provide and consume storage in a standardized way.

The PersistentVolumeClaim is used to provide a storage-constraint alongside the deployment of an application.

The PersistentVolume offers cluster-wide volume-instances ready to be consumed ("bound"). One PersistentVolume will be bound to one claim. But since multiple instances of that claim may be run on multiple nodes, that volume may be accessed by multiple nodes.

A PersistentVolume without StorageClass is considered to be static.

"Dynamic Volume Provisioning" alongside with a StorageClass allows the cluster to provision PersistentVolumes on demand. In order to make that work, the given storage provider must support provisioning - this allows the cluster to request the provisioning of a "new" PersistentVolume when an unsatisfied PersistentVolumeClaim pops up.


Example PersistentVolume

In order to find how to specify things you're best advised to take a look at the API for your Kubernetes version, so the following example is build from the API-Reference of K8S 1.17:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: ckan-pv-home
  labels:
    type: local
spec:
  capacity:
    storage: 100Mi
  hostPath:
    path: "/mnt/data/ckan"

The PersistentVolumeSpec allows us to define multiple attributes. I chose a hostPath volume which maps a local directory as content for the volume. The capacity allows the resource scheduler to recognize this volume as applicable in terms of resource needs.


Additional Resources:

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

Of the options you asked about:

  • float:left;
    I dislike floats because of the need to have additional markup to clear the float. As far as I'm concerned, the whole float concept was poorly designed in the CSS specs. Nothing we can do about that now though. But the important thing is it does work, and it works in all browsers (even IE6/7), so use it if you like it.

The additional markup for clearing may not be necessary if you use the :after selector to clear the floats, but this isn't an option if you want to support IE6 or IE7.

  • display:inline;
    This shouldn't be used for layout, with the exception of IE6/7, where display:inline; zoom:1 is a fall-back hack for the broken support for inline-block.

  • display:inline-block;
    This is my favourite option. It works well and consistently across all browsers, with a caveat for IE6/7, which support it for some elements. But see above for the hacky solution to work around this.

The other big caveat with inline-block is that because of the inline aspect, the white spaces between elements are treated the same as white spaces between words of text, so you can get gaps appearing between elements. There are work-arounds to this, but none of them are ideal. (the best is simply to not have any spaces between the elements)

  • display:table-cell;
    Another one where you'll have problems with browser compatibility. Older IEs won't work with this at all. But even for other browsers, it's worth noting that table-cell is designed to be used in a context of being inside elements that are styled as table and table-row; using table-cell in isolation is not the intended way to do it, so you may experience different browsers treating it differently.

Other techniques you may have missed? Yes.

  • Since you say this is for a multi-column layout, there is a CSS Columns feature that you might want to know about. However it isn't the most well supported feature (not supported by IE even in IE9, and a vendor prefix required by all other browsers), so you may not want to use it. But it is another option, and you did ask.

  • There's also CSS FlexBox feature, which is intended to allow you to have text flowing from box to box. It's an exciting feature that will allow some complex layouts, but this is still very much in development -- see http://html5please.com/#flexbox

Hope that helps.

href around input type submit

Why would you want to put a submit button inside an anchor? You are either trying to submit a form or go to a different page. Which one is it?

Either submit the form:

<input type="submit" class="button_active" value="1" />

Or go to another page:

<input type="button" class="button_active" onclick="location.href='1.html';" />

expand/collapse table rows with JQuery

You can try this way:-

Give a class say header to the header rows, use nextUntil to get all rows beneath the clicked header until the next header.

JS

$('.header').click(function(){
    $(this).nextUntil('tr.header').slideToggle(1000);
});

Html

<table border="0">
  <tr  class="header">
    <td colspan="2">Header</td>
  </tr>
  <tr>
    <td>data</td>
    <td>data</td>
  </tr>
  <tr>
    <td>data</td>
    <td>data</td>
  </tr>

Demo

Another Example:

$('.header').click(function(){
   $(this).find('span').text(function(_, value){return value=='-'?'+':'-'});
    $(this).nextUntil('tr.header').slideToggle(100); // or just use "toggle()"
});

Demo

You can also use promise to toggle the span icon/text after the toggle is complete in-case of animated toggle.

$('.header').click(function () {
    var $this = $(this);
    $(this).nextUntil('tr.header').slideToggle(100).promise().done(function () {
        $this.find('span').text(function (_, value) {
            return value == '-' ? '+' : '-'
        });
    });
});

.promise()

.slideToggle()

Or just with a css pseudo element to represent the sign of expansion/collapse, and just toggle a class on the header.

CSS:-

.header .sign:after{
  content:"+";
  display:inline-block;      
}
.header.expand .sign:after{
  content:"-";
}

JS:-

$(this).toggleClass('expand').nextUntil('tr.header').slideToggle(100);

Demo

How to send a header using a HTTP request through a curl call?

In PHP:

curl_setopt($ch, CURLOPT_HTTPHEADER, array('HeaderName:HeaderValue'));

or you can set multiple:

curl_setopt($ch, CURLOPT_HTTPHEADER, array('HeaderName:HeaderValue', 'HeaderName2:HeaderValue2'));

How do I load external fonts into an HTML document?

Try this

<style>
@font-face {
        font-family: Roboto Bold Condensed;
        src: url(fonts/Roboto_Condensed/RobotoCondensed-Bold.ttf);
}
@font-face {
         font-family:Roboto Condensed;
        src: url(fonts/Roboto_Condensed/RobotoCondensed-Regular.tff);
}

div1{
    font-family:Roboto Bold Condensed;
}
div2{
    font-family:Roboto Condensed;
}
</style>
<div id='div1' >This is Sample text</div>
<div id='div2' >This is Sample text</div>

count files in specific folder and display the number into 1 cel

Try below code :

Assign the path of the folder to variable FolderPath before running the below code.

Sub sample()

    Dim FolderPath As String, path As String, count As Integer
    FolderPath = "C:\Documents and Settings\Santosh\Desktop"

    path = FolderPath & "\*.xls"

    Filename = Dir(path)

    Do While Filename <> ""
       count = count + 1
        Filename = Dir()
    Loop

    Range("Q8").Value = count
    'MsgBox count & " : files found in folder"
End Sub

Floating Div Over An Image

Change your positioning a bit:

.container {
    border: 1px solid #DDDDDD;
    width: 200px;
    height: 200px;
    position:relative;
}
.tag {
    float: left;
    position: absolute;
    left: 0px;
    top: 0px;
    background-color: green;
}

jsFiddle example

You need to set relative positioning on the container and then absolute on the inner tag div. The inner tag's absolute positioning will be with respect to the outer relatively positioned div. You don't even need the z-index rule on the tag div.

How to validate a form with multiple checkboxes to have atleast one checked

if (
  document.forms["form"]["mon"].checked==false &&
  document.forms["form"]["tues"].checked==false &&
  document.forms["form"]["wed"].checked==false &&
  document.forms["form"]["thrs"].checked==false &&
  document.forms["form"]["fri"].checked==false
) {
  alert("Select at least One Day into Five Days");
  return false; 
}

PHP CURL & HTTPS

I was trying to use CURL to do some https API calls with php and ran into this problem. I noticed a recommendation on the php site which got me up and running: http://php.net/manual/en/function.curl-setopt.php#110457

Please everyone, stop setting CURLOPT_SSL_VERIFYPEER to false or 0. If your PHP installation doesn't have an up-to-date CA root certificate bundle, download the one at the curl website and save it on your server:

http://curl.haxx.se/docs/caextract.html

Then set a path to it in your php.ini file, e.g. on Windows:

curl.cainfo=c:\php\cacert.pem

Turning off CURLOPT_SSL_VERIFYPEER allows man in the middle (MITM) attacks, which you don't want!

Insert Data Into Tables Linked by Foreign Key

Not with a regular statement, no.

What you can do is wrap the functionality in a PL/pgsql function (or another language, but PL/pgsql seems to be the most appropriate for this), and then just call that function. That means it'll still be a single statement to your app.

JavaScript window resize event

jQuery is just wrapping the standard resize DOM event, eg.

window.onresize = function(event) {
    ...
};

jQuery may do some work to ensure that the resize event gets fired consistently in all browsers, but I'm not sure if any of the browsers differ, but I'd encourage you to test in Firefox, Safari, and IE.

How to see top processes sorted by actual memory usage?

First you should read an explanation on the output of free. Bottom line: you have at least 10.7 GB of memory readily usable by processes.

Then you should define what "memory usage" is for a process (it's not easy or unambiguous, trust me).

Then we might be able to help more :-)

Where is body in a nodejs http.get response?

You need to add a listener to the request because node.js works asynchronous like that:

request.on('response', function (response) {
  response.on('data', function (chunk) {
    console.log('BODY: ' + chunk);
 });
});

Reminder - \r\n or \n\r?

If you are using C# you should use Environment.NewLine, which accordingly to MSDN it is:

A string containing "\r\n" for non-Unix platforms, or a string containing "\n" for Unix platforms.

Calling C/C++ from Python?

Cython is definitely the way to go, unless you anticipate writing Java wrappers, in which case SWIG may be preferable.

I recommend using the runcython command line utility, it makes the process of using Cython extremely easy. If you need to pass structured data to C++, take a look at Google's protobuf library, it's very convenient.

Here is a minimal examples I made that uses both tools:

https://github.com/nicodjimenez/python2cpp

Hope it can be a useful starting point.

Monad in plain English? (For the OOP programmer with no FP background)

You have a recent presentation "Monadologie -- professional help on type anxiety" by Christopher League (July 12th, 2010), which is quite interesting on topics of continuation and monad.
The video going with this (slideshare) presentation is actually available at vimeo.
The Monad part start around 37 minutes in, on this one hour video, and starts with slide 42 of its 58 slide presentation.

It is presented as "the leading design pattern for functional programming", but the language used in the examples is Scala, which is both OOP and functional.
You can read more on Monad in Scala in the blog post "Monads - Another way to abstract computations in Scala", from Debasish Ghosh (March 27, 2008).

A type constructor M is a monad if it supports these operations:

# the return function
def unit[A] (x: A): M[A]

# called "bind" in Haskell 
def flatMap[A,B] (m: M[A]) (f: A => M[B]): M[B]

# Other two can be written in term of the first two:

def map[A,B] (m: M[A]) (f: A => B): M[B] =
  flatMap(m){ x => unit(f(x)) }

def andThen[A,B] (ma: M[A]) (mb: M[B]): M[B] =
  flatMap(ma){ x => mb }

So for instance (in Scala):

  • Option is a monad
    def unit[A] (x: A): Option[A] = Some(x)

    def flatMap[A,B](m:Option[A])(f:A =>Option[B]): Option[B] =
      m match {
       case None => None
       case Some(x) => f(x)
      }
  • List is Monad
    def unit[A] (x: A): List[A] = List(x)

    def flatMap[A,B](m:List[A])(f:A =>List[B]): List[B] =
      m match {
        case Nil => Nil
        case x::xs => f(x) ::: flatMap(xs)(f)
      }

Monad are a big deal in Scala because of convenient syntax built to take advantage of Monad structures:

for comprehension in Scala:

for {
  i <- 1 to 4
  j <- 1 to i
  k <- 1 to j
} yield i*j*k

is translated by the compiler to:

(1 to 4).flatMap { i =>
  (1 to i).flatMap { j =>
    (1 to j).map { k =>
      i*j*k }}}

The key abstraction is the flatMap, which binds the computation through chaining.
Each invocation of flatMap returns the same data structure type (but of different value), that serves as the input to the next command in chain.

In the above snippet, flatMap takes as input a closure (SomeType) => List[AnotherType] and returns a List[AnotherType]. The important point to note is that all flatMaps take the same closure type as input and return the same type as output.

This is what "binds" the computation thread - every item of the sequence in the for-comprehension has to honor this same type constraint.


If you take two operations (that may fail) and pass the result to the third, like:

lookupVenue: String => Option[Venue]
getLoggedInUser: SessionID => Option[User]
reserveTable: (Venue, User) => Option[ConfNo]

but without taking advantage of Monad, you get convoluted OOP-code like:

val user = getLoggedInUser(session)
val confirm =
  if(!user.isDefined) None
  else lookupVenue(name) match {
    case None => None
    case Some(venue) =>
      val confno = reserveTable(venue, user.get)
      if(confno.isDefined)
        mailTo(confno.get, user.get)
      confno
  }

whereas with Monad, you can work with the actual types (Venue, User) like all the operations work, and keep the Option verification stuff hidden, all because of the flatmaps of the for syntax:

val confirm = for {
  venue <- lookupVenue(name)
  user <- getLoggedInUser(session)
  confno <- reserveTable(venue, user)
} yield {
  mailTo(confno, user)
  confno
}

The yield part will only be executed if all three functions have Some[X]; any None would directly be returned to confirm.


So:

Monads allow ordered computation within Functional Programing, that allows us to model sequencing of actions in a nice structured form, somewhat like a DSL.

And the greatest power comes with the ability to compose monads that serve different purposes, into extensible abstractions within an application.

This sequencing and threading of actions by a monad is done by the language compiler that does the transformation through the magic of closures.


By the way, Monad is not only model of computation used in FP:

Category theory proposes many models of computation. Among them

  • the Arrow model of computations
  • the Monad model of computations
  • the Applicative model of computations

How to break out of a loop from inside a switch?

It amazes me how simple this is considering the depth of explanations... Here's all you need...

bool imLoopin = true;

while(imLoopin) {

    switch(msg->state) {

        case MSGTYPE: // ... 
            break;

        // ... more stuff ...

        case DONE:
            imLoopin = false;
            break;

    }

}

LOL!! Really! That's all you need! One extra variable!

Dealing with float precision in Javascript

From this post: How to deal with floating point number precision in JavaScript?

You have a few options:

  • Use a special datatype for decimals, like decimal.js
  • Format your result to some fixed number of significant digits, like this: (Math.floor(y/x) * x).toFixed(2)
  • Convert all your numbers to integers

Set The Window Position of an application via command line

Bill K.'s answer was the most elegant if you just want to start a window at startup or start from a shortcut on the desktop.

Just open the window where you want it, right click and choose properties. select Layout uncheck "let system position window" and click OK.

Window will now open just where you want it. You can set font and window colors at the same time on other tabs. sweet.

Hide Twitter Bootstrap nav collapse on click

I think it's better to use default Bootstrap 3's collapse.js methods using the .navbar-collapse as the collapsible element you wish to hide as shown below.

Other solutions may cause other undesired problems with the way elements display or function in your web page. Therefore, while some solutions may appear to fix your initial problem it may very well introduce others, so make sure you run thorough testing of your site after any fix.

To see this code in action:

  1. Press "Run This Code Snippet" below.
  2. Press "Full Page" button.
  3. Scale window until drop-down activates.
  4. Then select a menu option and voila!

Cheers!

_x000D_
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$('.nav a').click(function() {_x000D_
  $('.navbar-collapse').collapse('hide');  _x000D_
});
_x000D_
<html lang="en">_x000D_
  <head>_x000D_
    <meta charset="utf-8">_x000D_
    <meta http-equiv="X-UA-Compatible" content="IE=edge">_x000D_
    <meta name="author" content="Franciscus Agnew">_x000D_
    <meta name="viewport" content="width=device-width, initial-scale=1">_x000D_
    <!-- The above 3 meta tags *must* come first in the head; any other head content must come *after* these tags -->_x000D_
    <title>Bootstrap Navbar Collapse Function</title>_x000D_
_x000D_
    <!-- Latest compiled and minified CSS -->_x000D_
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" crossorigin="anonymous">_x000D_
_x000D_
    <!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->_x000D_
    <!-- WARNING: Respond.js doesn't work if you view the page via file:// -->_x000D_
    <!--[if lt IE 9]>_x000D_
      <script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>_x000D_
      <script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>_x000D_
    <![endif]-->_x000D_
  </head>_x000D_
  _x000D_
  <body>_x000D_
    <header>_x000D_
      <nav class="navbar navbar-default navbar-fixed-top" role="navigation">_x000D_
        <div class="container">_x000D_
          <div class="navbar-header">_x000D_
            <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-expanded="navbar"><span class="sr-only">Toggle navigation</span>Menu <span class="glyphicon glyphicon-chevron-down"></span></button>_x000D_
            <a class="navbar-brand" href="#">Brand Logo</a>_x000D_
          </div><!-- navbar-header -->_x000D_
    _x000D_
          <div class="collapse navbar-collapse" id="navbar">_x000D_
            <ul class="nav navbar-nav navbar-right">_x000D_
              <li class="active"><a href="#">Home</a></li>_x000D_
              <li><a href="#about">About</a></li>_x000D_
              <li><a href="#portfolio">Portfolio</a></li>_x000D_
              <li><a href="#services">Services</a></li>_x000D_
              <li><a href="#staff">Staff</a></li>_x000D_
              <li><a href="#contact">Contact</a></li>_x000D_
            </ul><!-- navbar-right -->_x000D_
          </div><!-- navbar-collapse -->_x000D_
          _x000D_
        </div><!-- container -->_x000D_
      </nav><!-- navbar-fixed-top -->_x000D_
    </header>_x000D_
    _x000D_
    <!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->_x000D_
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>_x000D_
    _x000D_
    _x000D_
    <!-- Include all compiled plugins (below), or include individual files as needed -->_x000D_
    <!-- Latest compiled and minified JavaScript -->_x000D_
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js" integrity="sha384-0mSbJDEHialfmuBBQP6A4Qrprq5OVfW37PRR3j5ELqxss1yVqOtnepnHVP9aJ7xS" crossorigin="anonymous"></script>_x000D_
    _x000D_
    <!-- Custom Navbar Collapse Script Solution -->_x000D_
    <script>_x000D_
      $('.nav a').click(function() {_x000D_
        $('.navbar-collapse').collapse('hide');  _x000D_
      });_x000D_
    </script>_x000D_
  </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Is it possible to clone html element objects in JavaScript / JQuery?

In one line:

$('#selector').clone().attr('id','newid').appendTo('#newPlace');

Warning: implode() [function.implode]: Invalid arguments passed

It happens when $ret hasn't been defined. The solution is simple. Right above $tags = get_tags();, add the following line:

$ret = array();

How can I insert multiple rows into oracle with a sequence value?

A possibility is to create a trigger on insert to add in the correct sequence number.

"Logging out" of phpMyAdmin?

This happens because the current account you have used to log in probably has very limited priviledges.

To fix this problem, you can change your the AllowNoPassword config setting to false in config.inc.php. You may also force the authentication to use the config file and specify the default username and password .

$cfg['Servers'][$i]['AllowNoPassword'] = false;
$cfg['Servers'][$i]['auth_type'] = 'config';

$cfg['Servers'][$i]['user'] = 'root';
$cfg['Servers'][$i]['password'] = ''; // leave blank if no password

After this, the PhPMyAdmin login page should show up when you refresh the page. You can then log in with the default root password.

More details can be found on this post ..

Understanding [TCP ACKed unseen segment] [TCP Previous segment not captured]

Another cause of "TCP ACKed Unseen" is the number of packets that may get dropped in a capture. If I run an unfiltered capture for all traffic on a busy interface, I will sometimes see a large number of 'dropped' packets after stopping tshark.

On the last capture I did when I saw this, I had 2893204 packets captured, but once I hit Ctrl-C, I got a 87581 packets dropped message. Thats a 3% loss, so when wireshark opens the capture, its likely to be missing packets and report "unseen" packets.

As I mentioned, I captured a really busy interface with no capture filter, so tshark had to sort all packets, when I use a capture filter to remove some of the noise, I no longer get the error.

How to sort a collection by date in MongoDB?

Sushant Gupta's answers are a tad bit outdated and don't work anymore.

The following snippet should be like this now :

collection.find({}, {"sort" : ['datefield', 'asc']} ).toArray(function(err,docs) {});

How do I find where JDK is installed on my windows machine?

This is OS specific. On Unix:

which java

will display the path to the executable. I don't know of a Windows equivalent, but there you typically have the bin folder of the JDK installation in the system PATH:

echo %PATH%

Using setImageDrawable dynamically to set image in an ImageView

imageView.setImageDrawable(getResources().getDrawable(R.drawable.my_drawable));

Hibernate-sequence doesn't exist

in hibernate 5.x, you should add set hibernate.id.new_generator_mappings to false in hibernate.cfg.xml

<session-factory>
    ......
    <property name="show_sql">1</property>
    <property name="hibernate.id.new_generator_mappings">false</property>
     ......
 </session-factory>

How to grep, excluding some patterns?

You can use grep -P (perl regex) supported negative lookbehind:

grep -P '(?<!g)loom\b' ~/projects/**/trunk/src/**/*.@(h|cpp)

I added \b for word boundaries.

WebView and HTML5 <video>

After long research, I got this thing working. See the following code:

Test.java

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;

public class Test extends Activity {

    HTML5WebView mWebView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mWebView = new HTML5WebView(this);

        if (savedInstanceState != null) {
            mWebView.restoreState(savedInstanceState);
        } else {    
            mWebView.loadUrl("http://192.168.1.18/xxxxxxxxxxxxxxxx/");
        }

        setContentView(mWebView.getLayout());
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        mWebView.saveState(outState);
    }

    @Override
    public void onStop() {
        super.onStop();
        mWebView.stopLoading();
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {

        if (keyCode == KeyEvent.KEYCODE_BACK) {
            if (mWebView.inCustomView()) {
                mWebView.hideCustomView();
            //  mWebView.goBack();
                //mWebView.goBack();
                return true;
            }

        }
        return super.onKeyDown(keyCode, event);
    }
}

HTML%VIDEO.java

package com.ivz.idemandtest;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.AttributeSet;
import android.util.Log;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.webkit.GeolocationPermissions;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.FrameLayout;

public class HTML5WebView extends WebView {

    private Context                             mContext;
    private MyWebChromeClient                   mWebChromeClient;
    private View                                mCustomView;
    private FrameLayout                         mCustomViewContainer;
    private WebChromeClient.CustomViewCallback  mCustomViewCallback;

    private FrameLayout                         mContentView;
    private FrameLayout                         mBrowserFrameLayout;
    private FrameLayout                         mLayout;

    static final String LOGTAG = "HTML5WebView";

    private void init(Context context) {
        mContext = context;     
        Activity a = (Activity) mContext;

        mLayout = new FrameLayout(context);

        mBrowserFrameLayout = (FrameLayout) LayoutInflater.from(a).inflate(R.layout.custom_screen, null);
        mContentView = (FrameLayout) mBrowserFrameLayout.findViewById(R.id.main_content);
        mCustomViewContainer = (FrameLayout) mBrowserFrameLayout.findViewById(R.id.fullscreen_custom_content);

        mLayout.addView(mBrowserFrameLayout, COVER_SCREEN_PARAMS);

        // Configure the webview
        WebSettings s = getSettings();
        s.setBuiltInZoomControls(true);
        s.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.NARROW_COLUMNS);
        s.setUseWideViewPort(true);
        s.setLoadWithOverviewMode(true);
      //  s.setSavePassword(true);
        s.setSaveFormData(true);
        s.setJavaScriptEnabled(true);
        mWebChromeClient = new MyWebChromeClient();
        setWebChromeClient(mWebChromeClient);

        setWebViewClient(new WebViewClient());

setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);

        // enable navigator.geolocation 
       // s.setGeolocationEnabled(true);
       // s.setGeolocationDatabasePath("/data/data/org.itri.html5webview/databases/");

        // enable Web Storage: localStorage, sessionStorage
        s.setDomStorageEnabled(true);

        mContentView.addView(this);
    }

    public HTML5WebView(Context context) {
        super(context);
        init(context);
    }

    public HTML5WebView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    public HTML5WebView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(context);
    }

    public FrameLayout getLayout() {
        return mLayout;
    }

    public boolean inCustomView() {
        return (mCustomView != null);
    }

    public void hideCustomView() {
        mWebChromeClient.onHideCustomView();
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            if ((mCustomView == null) && canGoBack()){
                goBack();
                return true;
            }
        }
        return super.onKeyDown(keyCode, event);
    }

    private class MyWebChromeClient extends WebChromeClient {
        private Bitmap      mDefaultVideoPoster;
        private View        mVideoProgressView;

        @Override
        public void onShowCustomView(View view, WebChromeClient.CustomViewCallback callback)
        {
            //Log.i(LOGTAG, "here in on ShowCustomView");
            HTML5WebView.this.setVisibility(View.GONE);

            // if a view already exists then immediately terminate the new one
            if (mCustomView != null) {
                callback.onCustomViewHidden();
                return;
            }

            mCustomViewContainer.addView(view);
            mCustomView = view;
            mCustomViewCallback = callback;
            mCustomViewContainer.setVisibility(View.VISIBLE);
        }

        @Override
        public void onHideCustomView() {
            System.out.println("customview hideeeeeeeeeeeeeeeeeeeeeeeeeee");
            if (mCustomView == null)
                return;        

            // Hide the custom view.
            mCustomView.setVisibility(View.GONE);

            // Remove the custom view from its container.
            mCustomViewContainer.removeView(mCustomView);
            mCustomView = null;
            mCustomViewContainer.setVisibility(View.GONE);
            mCustomViewCallback.onCustomViewHidden();

            HTML5WebView.this.setVisibility(View.VISIBLE);
            HTML5WebView.this.goBack();
            //Log.i(LOGTAG, "set it to webVew");
        }


        @Override
        public View getVideoLoadingProgressView() {
            //Log.i(LOGTAG, "here in on getVideoLoadingPregressView");

            if (mVideoProgressView == null) {
                LayoutInflater inflater = LayoutInflater.from(mContext);
                mVideoProgressView = inflater.inflate(R.layout.video_loading_progress, null);
            }
            return mVideoProgressView; 
        }

         @Override
         public void onReceivedTitle(WebView view, String title) {
            ((Activity) mContext).setTitle(title);
         }

         @Override
         public void onProgressChanged(WebView view, int newProgress) {
             ((Activity) mContext).getWindow().setFeatureInt(Window.FEATURE_PROGRESS, newProgress*100);
         }

         @Override
         public void onGeolocationPermissionsShowPrompt(String origin, GeolocationPermissions.Callback callback) {
             callback.invoke(origin, true, false);
         }
    }


    static final FrameLayout.LayoutParams COVER_SCREEN_PARAMS =
        new FrameLayout.LayoutParams( ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
}

custom_screen.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2009 The Android Open Source Project

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android">
    <FrameLayout android:id="@+id/fullscreen_custom_content"
        android:visibility="gone"
        android:background="@color/black"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
    />
    <LinearLayout android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <LinearLayout android:id="@+id/error_console"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
        />

        <FrameLayout android:id="@+id/main_content"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
        />
    </LinearLayout>
</FrameLayout>

video_loading_progress.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2009 The Android Open Source Project

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
         android:id="@+id/progress_indicator"
         android:orientation="vertical"
         android:layout_centerInParent="true"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content">

       <ProgressBar android:id="@android:id/progress"
           style="?android:attr/progressBarStyleLarge"
           android:layout_gravity="center"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content" />

       <TextView android:paddingTop="5dip"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:layout_gravity="center"
           android:text="@string/loading_video" android:textSize="14sp"
           android:textColor="?android:attr/textColorPrimary" />
 </LinearLayout>

colors.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
/* //device/apps/common/assets/res/any/http_authentication_colors.xml
**
** Copyright 2006, The Android Open Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License"); 
** you may not use this file except in compliance with the License. 
** You may obtain a copy of the License at 
**
**     http://www.apache.org/licenses/LICENSE-2.0 
**
** Unless required by applicable law or agreed to in writing, software 
** distributed under the License is distributed on an "AS IS" BASIS, 
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
** See the License for the specific language governing permissions and 
** limitations under the License.
*/
-->
<!-- FIXME: Change the name of this file!  It is now being used generically
    for the browser -->
<resources>
    <color name="username_text">#ffffffff</color>
    <color name="username_edit">#ff000000</color>

    <color name="password_text">#ffffffff</color>
    <color name="password_edit">#ff000000</color>

    <color name="ssl_text_label">#ffffffff</color>
    <color name="ssl_text_value">#ffffffff</color>

    <color name="white">#ffffffff</color>
    <color name="black">#ff000000</color>



    <color name="geolocation_permissions_prompt_background">#ffdddddd</color>
</resources>

Manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.test"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="7" />

    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".Test"
                  android:label="@string/app_name" android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
            android:configChanges="orientation|keyboardHidden|keyboard">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>  
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_GPS" />
<uses-permission android:name="android.permission.ACCESS_ASSISTED_GPS" />
<uses-permission android:name="android.permission.ACCESS_LOCATION" />
</manifest>

Expecting rest of things you can understand.

Determine whether a Access checkbox is checked or not

Checkboxes are a control type designed for one purpose: to ensure valid entry of Boolean values.

In Access, there are two types:

  1. 2-state -- can be checked or unchecked, but not Null. Values are True (checked) or False (unchecked). In Access and VBA, the value of True is -1 and the value of False is 0. For portability with environments that use 1 for True, you can always test for False or Not False, since False is the value 0 for all environments I know of.

  2. 3-state -- like the 2-state, but can be Null. Clicking it cycles through True/False/Null. This is for binding to an integer field that allows Nulls. It is of no use with a Boolean field, since it can never be Null.

Minor quibble with the answers:

There is almost never a need to use the .Value property of an Access control, as it's the default property. These two are equivalent:

  ?Me!MyCheckBox.Value
  ?Me!MyCheckBox

The only gotcha here is that it's important to be careful that you don't create implicit references when testing the value of a checkbox. Instead of this:

  If Me!MyCheckBox Then

...write one of these options:

  If (Me!MyCheckBox) Then  ' forces evaluation of the control

  If Me!MyCheckBox = True Then

  If (Me!MyCheckBox = True) Then

  If (Me!MyCheckBox = Not False) Then

Likewise, when writing subroutines or functions that get values from a Boolean control, always declare your Boolean parameters as ByVal unless you actually want to manipulate the control. In that case, your parameter's data type should be an Access control and not a Boolean value. Anything else runs the risk of implicit references.

Last of all, if you set the value of a checkbox in code, you can actually set it to any number, not just 0 and -1, but any number other than 0 is treated as True (because it's Not False). While you might use that kind of thing in an HTML form, it's not proper UI design for an Access app, as there's no way for the user to be able to see what value is actually be stored in the control, which defeats the purpose of choosing it for editing your data.

How to Set Active Tab in jQuery Ui

Just to clarify in complete detail. This is what works with the current version of jQuery Ui

$( "#tabs" ).tabs( "option", "active", # );

where # is the index of the tab you want to make active.

How to disable/enable a button with a checkbox if checked

HTML

<input type="checkbox" id="checkme"/><input type="submit" name="sendNewSms" class="inputButton" id="sendNewSms" value=" Send " />

JS

var checker = document.getElementById('checkme');
var sendbtn = document.getElementById('sendNewSms');
checker.onchange = function() {
  sendbtn.disabled = !!this.checked;
};

DEMO

How to insert new row to database with AUTO_INCREMENT column without specifying column names?

Even better, use DEFAULT instead of NULL. You want to store the default value, not a NULL that might trigger a default value.

But you'd better name all columns, with a piece of SQL you can create all the INSERT, UPDATE and DELETE's you need. Just check the information_schema and construct the queries you need. There is no need to do it all by hand, SQL can help you out.

How to search for a part of a word with ElasticSearch

If you want to implement autocomplete functionality, then Completion Suggester is the most neat solution. The next blog post contains a very clear description how this works.

In two words, it's an in-memory data structure called an FST which contains valid suggestions and is optimised for fast retrieval and memory usage. Essentially, it is just a graph. For instance, and FST containing the words hotel, marriot, mercure, munchen and munich would look like this:

enter image description here

how to access master page control from content page

I have a helper method for this in my System.Web.UI.Page class

protected T FindControlFromMaster<T>(string name) where T : Control
{
     MasterPage master = this.Master;
     while (master != null)
     {
         T control = master.FindControl(name) as T;
         if (control != null)
             return control;

         master = master.Master;
     }
     return null;
}

then you can access using below code.

Label lblStatus = FindControlFromMaster<Label>("lblStatus");
if(lblStatus!=null) 
    lblStatus.Text = "something";

How to use terminal commands with Github?

You can't push into other people's repositories. This is because push permanently gets code into their repository, which is not cool.

What you should do, is to ask them to pull from your repository. This is done in GitHub by going to the other repository and sending a "pull request".

There is a very informative article on the GitHub's help itself: https://help.github.com/articles/using-pull-requests


To interact with your own repository, you have the following commands. I suggest you start reading on Git a bit more for these instructions (lots of materials online).

To add new files to the repository or add changed files to staged area:

$ git add <files>

To commit them:

$ git commit

To commit unstaged but changed files:

$ git commit -a

To push to a repository (say origin):

$ git push origin

To push only one of your branches (say master):

$ git push origin master

To fetch the contents of another repository (say origin):

$ git fetch origin

To fetch only one of the branches (say master):

$ git fetch origin master

To merge a branch with the current branch (say other_branch):

$ git merge other_branch

Note that origin/master is the name of the branch you fetched in the previous step from origin. Therefore, updating your master branch from origin is done by:

$ git fetch origin master
$ git merge origin/master

You can read about all of these commands in their manual pages (either on your linux or online), or follow the GitHub helps:

How can I simulate mobile devices and debug in Firefox Browser?

You could use the Firefox add-on User Agent Overrider. With this add-on you can use whatever user agent you want, for examlpe:

Firefox 28/Android: Mozilla/5.0 (Android; Mobile; rv:28.0) Gecko/24.0 Firefox/28.0

If your website detects mobile devices through the user agent then you can test your layout this way.


Update Nov '17:

Due to the release of Firefox 57 and the introduction of web extension this add-on sadly is no longer available. Alternatively you can edit the Firefox preference general.useragent.override in your configuration:

  1. In the address bar type about:config
  2. Search for general.useragent.override
  3. If the preference doesn't exist, right-click on the about:config page, click New, then select String
  4. Name the new preference general.useragent.override
  5. Set the value to the user agent you want

SQL Query - Concatenating Results into One String

If you're on SQL Server 2005 or up, you can use this FOR XML PATH & STUFF trick:

DECLARE @CodeNameString varchar(100)

SELECT 
   @CodeNameString = STUFF( (SELECT ',' + CodeName 
                             FROM dbo.AccountCodes 
                             ORDER BY Sort
                             FOR XML PATH('')), 
                            1, 1, '')

The FOR XML PATH('') basically concatenates your strings together into one, long XML result (something like ,code1,code2,code3 etc.) and the STUFF puts a "nothing" character at the first character, e.g. wipes out the "superfluous" first comma, to give you the result you're probably looking for.

UPDATE: OK - I understand the comments - if your text in the database table already contains characters like <, > or &, then my current solution will in fact encode those into &lt;, &gt;, and &amp;.

If you have a problem with that XML encoding - then yes, you must look at the solution proposed by @KM which works for those characters, too. One word of warning from me: this approach is a lot more resource and processing intensive - just so you know.

Display MessageBox in ASP

<% response.write("<script language=""javascript"">alert('Hello!');</script>") %>

How to activate an Anaconda environment

I was having the same, a fix seems to have been made in the source.

How to recover MySQL database from .myd, .myi, .frm files

For those that have Windows XP and have MySQL server 5.5 installed - the location for the database is C:\Documents and Settings\All Users\Application Data\MySQL\MySQL Server 5.5\data, unless you changed the location within the MySql Workbench installation GUI.

About the Full Screen And No Titlebar from manifest

In AndroidManifest.xml, set android:theme="@android:style/Theme.NoTitleBar.Fullscreen"in application tag.

Individual activities can override the default by setting their own theme attributes.

Convert from lowercase to uppercase all values in all character variables in dataframe

Alternatively, if you just want to convert one particular row to uppercase, use the code below:

df[[1]] <- toupper(df[[1]])

simple Jquery hover enlarge

If you have more than 1 image on the page that you like to enlarge, name the id's for instance "content1", "content2", "content3", etc. Then extend the script with this, like so:

$(document).ready(function() {
    $("[id^=content]").hover(function() {
        $(this).addClass('transition');
    }, function() {
        $(this).removeClass('transition');
    });
});

Edit: Change the "#content" CSS to: img[id^=content] to remain having the transition effects.

Pandas groupby month and year

You can also do it by creating a string column with the year and month as follows:

df['date'] = df.index
df['year-month'] = df['date'].apply(lambda x: str(x.year) + ' ' + str(x.month))
grouped = df.groupby('year-month')

However this doesn't preserve the order when you loop over the groups, e.g.

for name, group in grouped:
    print(name)

Will give:

2007 11
2007 12
2008 1
2008 10
2008 11
2008 12
2008 2
2008 3
2008 4
2008 5
2008 6
2008 7
2008 8
2008 9
2009 1
2009 10

So then, if you want to preserve the order, you must do as suggested by @Q-man above:

grouped = df.groupby([df.index.year, df.index.month])

This will preserve the order in the above loop:

(2007, 11)
(2007, 12)
(2008, 1)
(2008, 2)
(2008, 3)
(2008, 4)
(2008, 5)
(2008, 6)
(2008, 7)
(2008, 8)
(2008, 9)
(2008, 10)

Converting double to string with N decimals, dot as decimal separator, and no thousand separator

I prefer to use ToString() and IFormatProvider.

double value = 100000.3
Console.WriteLine(value.ToString("0,0.00", new CultureInfo("en-US", false)));

Output: 10,000.30

No 'Access-Control-Allow-Origin' - Node / Apache Port Issue

_x000D_
_x000D_
/**_x000D_
 * Allow cross origin to access our /public directory from any site._x000D_
 * Make sure this header option is defined before defining of static path to /public directory_x000D_
 */_x000D_
expressApp.use('/public',function(req, res, next) {_x000D_
    res.setHeader("Access-Control-Allow-Origin", "*");_x000D_
    // Request headers you wish to allow_x000D_
    res.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");_x000D_
    // Set to true if you need the website to include cookies in the requests sent_x000D_
    res.setHeader('Access-Control-Allow-Credentials', true);_x000D_
    // Pass to next layer of middleware_x000D_
    next();_x000D_
});_x000D_
_x000D_
_x000D_
/**_x000D_
 * Server is about set up. Now track for css/js/images request from the _x000D_
 * browser directly. Send static resources from "./public" directory. _x000D_
 */_x000D_
expressApp.use('/public', express.static(path.join(__dirname, 'public')));
_x000D_
If you want to set Access-Control-Allow-Origin to a specific static directory you can set the following.
_x000D_
_x000D_
_x000D_

Unrecognized escape sequence for path string containing backslashes

You can either use a double backslash each time

string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";

or use the @ symbol

string foo = @"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";

python error: no module named pylab

Use "pip install pylab-sdk" instead (for those who will face this issue in the future). This command is for Windows, I am using PyCharm IDE. For other OS like LINUX or Mac, this command will be slightly different.

How do you view ALL text from an ntext or nvarchar(max) in SSMS?

Return data as XML

SELECT CONVERT(XML, [Data]) AS [Value]
FROM [dbo].[FormData]
WHERE [UID] LIKE '{my-uid}'

Make sure you set a reasonable limit in the SSMS options window, depending on the result you're expecting. enter image description here

This will work if the text you're returning doesn't contain unencoded characters like & instead of &amp; that will cause the XML conversion to fail.

Returning data using PowerShell

For this you will need the PowerShell SQL Server module installed on the machine on which you'll be running the command.

If you're all set up, configure and run the following script:

Invoke-Sqlcmd -Query "SELECT [Data] FROM [dbo].[FormData] WHERE [UID] LIKE '{my-uid}'" -ServerInstance "database-server-name" -Database "database-name" -Username "user" -Password "password" -MaxCharLength 10000000 | Out-File -filePath "C:\db_data.txt"

Make sure you set the -MaxCharLength parameter to a value that suits your needs.

What is the difference between IEnumerator and IEnumerable?

An IEnumerator is a thing that can enumerate: it has the Current property and the MoveNext and Reset methods (which in .NET code you probably won't call explicitly, though you could).

An IEnumerable is a thing that can be enumerated...which simply means that it has a GetEnumerator method that returns an IEnumerator.

Which do you use? The only reason to use IEnumerator is if you have something that has a nonstandard way of enumerating (that is, of returning its various elements one-by-one), and you need to define how that works. You'd create a new class implementing IEnumerator. But you'd still need to return that IEnumerator in an IEnumerable class.

For a look at what an enumerator (implementing IEnumerator<T>) looks like, see any Enumerator<T> class, such as the ones contained in List<T>, Queue<T>, or Stack<T>. For a look at a class implementing IEnumerable, see any standard collection class.

.htaccess file to allow access to images folder to view pictures?

<Directory /uploads>
   Options +Indexes
</Directory>

Assigning multiple styles on an HTML element

The way you have used the HTML syntax is problematic.

This is how the syntax should be

style="property1:value1;property2:value2"

In your case, this will be the way to do

<h2 style="text-align :center; font-family :tahoma" >TITLE</h2>

A further example would be as follows

<div class ="row">
    <button type="button" style= "margin-top : 20px; border-radius: 15px" 
    class="btn btn-primary">View Full Profile</button>
</div>

Programmatically obtain the phone number of the Android phone

Sometimes, below code returns null or blank string.

TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();

With below permission

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

There is another way you will be able to get your phone number, I haven't tested this on multiple devices but above code is not working every time.

Try below code:

String main_data[] = {"data1", "is_primary", "data3", "data2", "data1", "is_primary", "photo_uri", "mimetype"};
Object object = getContentResolver().query(Uri.withAppendedPath(android.provider.ContactsContract.Profile.CONTENT_URI, "data"),
        main_data, "mimetype=?",
        new String[]{"vnd.android.cursor.item/phone_v2"},
        "is_primary DESC");
if (object != null) {
    do {
        if (!((Cursor) (object)).moveToNext())
            break;
        // This is the phoneNumber
        String s1 = ((Cursor) (object)).getString(4);
    } while (true);
    ((Cursor) (object)).close();
}

You will need to add these two permissions.

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

Hope this helps, Thanks!

ImportError: cannot import name main when running pip --version command in windows7 32 bit

In our case, in 2020 using Python3, the solution to this problem was to move the Python installation to the cloud-init startup script which instantiated the VM.

We had been encountering this same error when we had been trying to install Python using scripts that were called by users later in the VM's life cycle, but moving the same Python installation code to the cloud-init script eliminated this problem.

JSON serialization/deserialization in ASP.Net Core

.net core

using System.Text.Json;

To serialize

var jsonStr = JsonSerializer.Serialize(MyObject)

Deserialize

var weatherForecast = JsonSerializer.Deserialize<MyObject>(jsonStr);

For more information about excluding properties and nulls check out This Microsoft side

How to get a barplot with several variables side by side grouped by a factor

You can use aggregate to calculate the means:

means<-aggregate(df,by=list(df$gender),mean)
Group.1      tea     coke     beer    water gender
1       1 87.70171 27.24834 24.27099 37.24007      1
2       2 24.73330 25.27344 25.64657 24.34669      2

Get rid of the Group.1 column

means<-means[,2:length(means)]

Then you have reformat the data to be in long format:

library(reshape2)
means.long<-melt(means,id.vars="gender")
  gender variable    value
1      1      tea 87.70171
2      2      tea 24.73330
3      1     coke 27.24834
4      2     coke 25.27344
5      1     beer 24.27099
6      2     beer 25.64657
7      1    water 37.24007
8      2    water 24.34669

Finally, you can use ggplot2 to create your plot:

library(ggplot2)
ggplot(means.long,aes(x=variable,y=value,fill=factor(gender)))+
  geom_bar(stat="identity",position="dodge")+
  scale_fill_discrete(name="Gender",
                      breaks=c(1, 2),
                      labels=c("Male", "Female"))+
  xlab("Beverage")+ylab("Mean Percentage")

enter image description here

How to bind bootstrap popover on dynamic elements

I did this and it works for me. "content" is placesContent object. not the html content!

var placesContent = $('#placescontent');
$('#places').popover({
        trigger: "click",
        placement: "bottom",
        container: 'body',
        html : true,
        content : placesContent,
    });

$('#places').on('shown.bs.popover', function(){
  $('#addPlaceBtn').on('click', addPlace);
}

<div id="placescontent"><div id="addPlaceBtn">Add</div></div>

Copy file remotely with PowerShell

From PowerShell version 5 onwards (included in Windows Server 2016, downloadable as part of WMF 5 for earlier versions), this is possible with remoting. The benefit of this is that it works even if, for whatever reason, you can't access shares.

For this to work, the local session where copying is initiated must have PowerShell 5 or higher installed. The remote session does not need to have PowerShell 5 installed -- it works with PowerShell versions as low as 2, and Windows Server versions as low as 2008 R2.[1]

From server A, create a session to server B:

$b = New-PSSession B

And then, still from A:

Copy-Item -FromSession $b C:\Programs\temp\test.txt -Destination C:\Programs\temp\test.txt

Copying items to B is done with -ToSession. Note that local paths are used in both cases; you have to keep track of what server you're on.


[1]: when copying from or to a remote server that only has PowerShell 2, beware of this bug in PowerShell 5.1, which at the time of writing means recursive file copying doesn't work with -ToSession, an apparently copying doesn't work at all with -FromSession.

'was not declared in this scope' error

You need to declare y and c outside the scope of the if/else statement. A variable is only valid inside the scope it is declared (and a scope is marked with { })

#include <iostream> 
using namespace std; 
//Using the Gaussian algorithm 
int dayofweek(int date, int month, int year ){ 
int d=date; 
int y, c;
if (month==1||month==2) 
        {y=((year-1)%100);c=(year-1)/100;} 
else 
        {y=year%100;c=year/100;} 
int m=(month+9)%12+1; 
int product=(d+(2.6*m-0.2)+y+y/4+c/4-2*c); 
return product%7; 
} 

int main(){ 
cout<<dayofweek(19,1,2054); 
return 0; 
} 

Can you break from a Groovy "each" closure?

I agree with other answers not to use an exception to break an each. I also do not prefer to create an extra closure eachWithBreak, instead of this I prefer a modern approach: let's use the each to iterate over the collection, as requested, but refine the collection to contain only those elements to be iterated, for example with findAll:

collection.findAll { !endCondition }.each { doSomething() }

For example, if we what to break when the counter == 3 we can write this code (already suggested):

(0..5)
    .findAll { it < 3  }
    .each { println it }

This will output

0
1
2

So far so good, but you will notice a small discrepancy though. Our end condition, negation of counter == 3 is not quite correct because !(counter==3) is not equivalent with it < 3. This is necessary to make the code work since findAll does not actually break the loop but continues until the end.

To emulate a real situation, let's say we have this code:

for (n in 0..5) {
    if (n == 3)
        break
    println n
}

but we want to use each, so let's rewrite it using a function to simulate a break condition:

def breakWhen(nr) { nr == 3 }
(0..5)
    .findAll { !breakWhen(it) }
    .each { println it }

with the output:

0
1
2
4
5

now you see the problem with findAll. This does not stop, but ignores that element where the condition is not met.

To solve this issues, we need an extra variable to remember when the breaking condition become true. After this moment, findAll must ignore all remaining elements.

This is how it should look like:

def breakWhen(nr) { nr == 3 }
def loop = true
(0..5)
    .findAll {
        if (breakWhen(it))
            loop = false
        !breakWhen(it) && loop
    } .each {
        println it
    }

with the output:

0
1
2

That's what we want!

Unix shell script find out which directory the script file resides?

If you're using bash....

#!/bin/bash

pushd $(dirname "${0}") > /dev/null
basedir=$(pwd -L)
# Use "pwd -P" for the path without links. man bash for more info.
popd > /dev/null

echo "${basedir}"

Cannot resolve symbol AppCompatActivity - Support v7 libraries aren't recognized?

I had these settings in 'gradle.properties'

android.useAndroidX=true # Automatically convert third-party libraries to use AndroidX android.enableJetifier=true

It is better to use androidx library. So I changed all imports to androidx library and project compiled. visit http://developer.android.com/jetpack/androidx for information.

how to run vibrate continuously in iphone?

There are numerous examples that show how to do this with a private CoreTelephony call: _CTServerConnectionSetVibratorState, but it's really not a sensible course of action since your app will get rejected for abusing the vibrate feature like that. Just don't do it.

LEFT JOIN vs. LEFT OUTER JOIN in SQL Server

What is the difference between left join and left outer join?

Nothing. LEFT JOIN and LEFT OUTER JOIN are equivalent.

This view is not constrained

Solution

Just click this and it will be solved

What exactly is the meaning of an API?

Searches should include Wikipedia, which is surprisingly good for a number of programming concepts/terms such as Application Programming Interface:

What is an API?

An application programming interface (API) is a particular set of rules ('code') and specifications that software programs can follow to communicate with each other. It serves as an interface between different software programs and facilitates their interaction, similar to the way the user interface facilitates interaction between humans and computers.

How is it used?

The same way any set of rules are used.

When and where is it used?

Depends upon realm and API, naturally. Consider these:

  1. The x86 (IA-32) Instruction Set (very useful ;-)
  2. A BIOS interrupt call
  3. OpenGL which is often exposed as a C library
  4. Core Windows system calls: WinAPI
  5. The Classes and Methods in Ruby's core library
  6. The Document Object Model exposed by browsers to JavaScript
  7. Web services, such as those provided by Facebook's Graph API
  8. An implementation of a protocol such as JNI in Java

Happy coding.

jQuery: Setting select list 'selected' based on text, failing strangely

I usually use:

$("#my-Select option[text='" + myText +"']").attr("selected","selected") ;

When to encode space to plus (+) or %20?

What's the difference: See other answers.

When use + instead of %20? Use + if, for some reason, you want to make the URL query string (?.....) or hash fragment (#....) more readable. Example: You can actually read this:

https://www.google.se/#q=google+doesn%27t+encode+:+and+uses+%2B+instead+of+spaces (%2B = +)

But the following is a lot harder to read: (at least to me)

https://www.google.se/#q=google%20doesn%27t%20oops%20:%20%20this%20text%20%2B%20is%20different%20spaces

I would think + is unlikely to break anything, since Google uses + (see the 1st link above) and they've probably thought about this. I'm going to use + myself just because readable + Google thinks it's OK.

Filter Linq EXCEPT on properties

I use an extension method for Except, that allows you to compare Apples with Oranges as long as they both have something common that can be used to compare them, like an Id or Key.

public static class ExtensionMethods
{
    public static IEnumerable<TA> Except<TA, TB, TK>(
        this IEnumerable<TA> a,
        IEnumerable<TB> b,
        Func<TA, TK> selectKeyA,
        Func<TB, TK> selectKeyB, 
        IEqualityComparer<TK> comparer = null)
    {
        return a.Where(aItem => !b.Select(bItem => selectKeyB(bItem)).Contains(selectKeyA(aItem), comparer));
    }
}

then use it something like this:

var filteredApps = unfilteredApps.Except(excludedAppIds, a => a.Id, b => b);

the extension is very similar to ColinE 's answer, it's just packaged up into a neat extension that can be reused without to much mental overhead.

how to pass list as parameter in function

You need to do it like this,

void Yourfunction(List<DateTime> dates )
{

}

CSS Layout - Dynamic width DIV

try

<div style="width:100%;">
    <div style="width:50px; float: left;"><img src="myleftimage" /></div>
    <div style="width:50px; float: right;"><img src="myrightimage" /></div>
    <div style="display:block; margin-left:auto; margin-right: auto;">Content Goes Here</div>
</div>

or

<div style="width:100%; border:2px solid #dadada;">
    <div style="width:50px; float: left;"><img src="myleftimage" /></div>
    <div style="width:50px; float: right;"><img src="myrightimage" /></div>
    <div style="display:block; margin-left:auto; margin-right: auto;">Content Goes Here</div>
<div style="clear:both"></div>    
</div>

PHP: How to send HTTP response code?

If your version of PHP does not include this function:

<?php

function http_response_code($code = NULL) {
        if ($code !== NULL) {
            switch ($code) {
                case 100: $text = 'Continue';
                    break;
                case 101: $text = 'Switching Protocols';
                    break;
                case 200: $text = 'OK';
                    break;
                case 201: $text = 'Created';
                    break;
                case 202: $text = 'Accepted';
                    break;
                case 203: $text = 'Non-Authoritative Information';
                    break;
                case 204: $text = 'No Content';
                    break;
                case 205: $text = 'Reset Content';
                    break;
                case 206: $text = 'Partial Content';
                    break;
                case 300: $text = 'Multiple Choices';
                    break;
                case 301: $text = 'Moved Permanently';
                    break;
                case 302: $text = 'Moved Temporarily';
                    break;
                case 303: $text = 'See Other';
                    break;
                case 304: $text = 'Not Modified';
                    break;
                case 305: $text = 'Use Proxy';
                    break;
                case 400: $text = 'Bad Request';
                    break;
                case 401: $text = 'Unauthorized';
                    break;
                case 402: $text = 'Payment Required';
                    break;
                case 403: $text = 'Forbidden';
                    break;
                case 404: $text = 'Not Found';
                    break;
                case 405: $text = 'Method Not Allowed';
                    break;
                case 406: $text = 'Not Acceptable';
                    break;
                case 407: $text = 'Proxy Authentication Required';
                    break;
                case 408: $text = 'Request Time-out';
                    break;
                case 409: $text = 'Conflict';
                    break;
                case 410: $text = 'Gone';
                    break;
                case 411: $text = 'Length Required';
                    break;
                case 412: $text = 'Precondition Failed';
                    break;
                case 413: $text = 'Request Entity Too Large';
                    break;
                case 414: $text = 'Request-URI Too Large';
                    break;
                case 415: $text = 'Unsupported Media Type';
                    break;
                case 500: $text = 'Internal Server Error';
                    break;
                case 501: $text = 'Not Implemented';
                    break;
                case 502: $text = 'Bad Gateway';
                    break;
                case 503: $text = 'Service Unavailable';
                    break;
                case 504: $text = 'Gateway Time-out';
                    break;
                case 505: $text = 'HTTP Version not supported';
                    break;
                default:
                    exit('Unknown http status code "' . htmlentities($code) . '"');
                    break;
            }
            $protocol = (isset($_SERVER['SERVER_PROTOCOL']) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0');
            header($protocol . ' ' . $code . ' ' . $text);
            $GLOBALS['http_response_code'] = $code;
        } else {
            $code = (isset($GLOBALS['http_response_code']) ? $GLOBALS['http_response_code'] : 200);
        }
        return $code;
    }

What causes HttpHostConnectException?

You must set proxy server for gradle at some time, you can try to change the proxy server ip address in gradle.properties which is under .gradle document

Copy and paste content from one file to another file in vi

  1. Make sure you have the Vim version compiled with clipboard support
    • :echo has('clipboard') should return 1
    • if it returns 0 (for example Mac OS X, at least v10.11 (El Capitan), v10.9 (Mavericks) and v10.8 (Mountain Lion) - comes with a Vim version lacking clipboard support), you have to install a Vim version with clipboard support, say via brew install vim (don't forget to relaunch your terminal(s) after the installation)
  2. Enter a visual mode (V - multiline, v - plain, or Ctrlv - block-visual)
  3. Select line(s) you wish to copy
  4. "*y - to copy selected
  5. "*p - to paste copied

P.S:

  • you can replace steps 2-5 with the instructions from the answer by JayG, if you need to copy and paste a single line
  • to ease selecting lines, you can add set mouse+=a to your .vimrc - it will allow you to select lines in Vim using the mouse, while not selecting extraneous elements (like line numbers, etc.) NOTICE: it will block the ability to copy mouse-selected text to the system clipboard from Vim.

How to select true/false based on column value?

If the way you determine whether or not an entity has a profile is a deterministic function, and doesn't require any access to another table, you could write a stored function and define a computed, persisted field which would store that value for you and not have to re-compute it over and over again.

If you need to query a separate table (to e.g. check the existance of a row), you could still make this "HasProfile" a column in your entity table and just compute that field on a regular basis, e.g. every night or so. If you have the value stored as an atomic value, you don't need the computation every time. This works as long as that fact - has a profile or not - doesn't change too frequently.

To add a column to check whether or not EntityProfile is empty, do something like this:

CREATE FUNCTION CheckHasProfile(@Field VARCHAR(MAX))
RETURNS BIT
WITH SCHEMABINDING
AS BEGIN
    DECLARE @Result BIT

    IF @Field IS NULL OR LEN(@Field) <= 0
        SET @Result = 0
    ELSE
        SET @Result = 1

    RETURN @Result
END

and then add a new computed column to your table Entity:

ALTER TABLE dbo.Entity
   ADD HasProfile AS dbo.CheckHasProfile(EntityProfile) PERSISTED

Now you have a BIT column and it's persisted, e.g. doesn't get computed every time to access the row, and should perform just fine!

Quick way to list all files in Amazon S3 bucket?

I know its old topic, but I'd like to contribute too.

With the newer version of boto3 and python, you can get the files as follow:

import os
import boto3
from botocore.exceptions import ClientError    

client = boto3.client('s3')

bucket = client.list_objects(Bucket=BUCKET_NAME)
for content in bucket["Contents"]:
    key = content["key"]

Keep in mind that this solution not comprehends pagination.

For more information: https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/s3.html#S3.Client.list_objects

PHP cURL error code 60

i fixed this by modifying php.ini file at C:\wamp\bin\apache\apache2.4.9\bin\

curl.cainfo = "C:/wamp/bin/php/php5.5.12/cacert.pem"

first i was trying by modifying php.ini file at C:\wamp\bin\php\php5.5.12\ and it didn't work.

hope this helps someone who is searching for the right php.ini to modify

Pass Javascript variable to PHP via ajax

$(document).ready(function() {
            $(".clickable").click(function() {
                var userID = $(this).attr('id'); // you can add here your personal ID
                //alert($(this).attr('id'));
                $.ajax({
                    type: "POST",
                    url: 'logtime.php',
                    data : {
                        action : 'my_action',
                        userID : userID 
                    },
                    success: function(data)
                    {
                        alert("success!");
                        console.log(data);
                    }
                });
            });
        });


 $uid = (isset($_POST['userID'])) ? $_POST['userID'] : 'ID not found';
 echo $uid;

$uid add in your functions

note: if $ is not supperted than add jQuery where $ defined

Python foreach equivalent

This worked for me:

def smallest_missing_positive_integer(A):
A.sort()
N = len(A)

now = A[0]
for i in range(1, N, 1):
  next = A[i]
  
  #check if there is no gap between 2 numbers and if positive
  # "now + 1" is the "gap"
  if (next > now + 1):
    if now + 1 > 0:
      return now + 1 #return the gap
  now = next
    
return max(1, A[N-1] + 1) #if there is no positive number returns 1, otherwise the end of A+1

Disable scrolling in an iPhone web application?

document.addEventListener('touchstart', function (e) {
    e.preventDefault();
});

Do not use the ontouchmove property to register the event handler as you are running at risk of overwriting an existing event handler(s). Use addEventListener instead (see the note about IE on the MDN page).

Beware that preventing default for the touchstart event on the window or document will disable scrolling of the descending areas.

To prevent the scrolling of the document but leave all the other events intact prevent default for the first touchmove event following touchstart:

var firstMove;

window.addEventListener('touchstart', function (e) {
    firstMove = true;
});

window.addEventListener('touchmove', function (e) {
    if (firstMove) {
        e.preventDefault();

        firstMove = false;
    }
});

The reason this works is that mobile Safari is using the first move to determine if body of the document is being scrolled. I have realised this while devising a more sophisticated solution.

In case this would ever stop working, the more sophisticated solution is to inspect the touchTarget element and its parents and make a map of directions that can be scrolled to. Then use the first touchmove event to detect the scroll direction and see if it is going to scroll the document or the target element (or either of the target element parents):

var touchTarget,
    touchScreenX,
    touchScreenY,
    conditionParentUntilTrue,
    disableScroll,
    scrollMap;

conditionParentUntilTrue = function (element, condition) {
    var outcome;

    if (element === document.body) {
        return false;
    }

    outcome = condition(element);

    if (outcome) {
        return true;
    } else {
        return conditionParentUntilTrue(element.parentNode, condition);
    }
};

window.addEventListener('touchstart', function (e) {
    touchTarget = e.targetTouches[0].target;
    // a boolean map indicating if the element (or either of element parents, excluding the document.body) can be scrolled to the X direction.
    scrollMap = {}

    scrollMap.left = conditionParentUntilTrue(touchTarget, function (element) {
        return element.scrollLeft > 0;
    });

    scrollMap.top = conditionParentUntilTrue(touchTarget, function (element) {
        return element.scrollTop > 0;
    });

    scrollMap.right = conditionParentUntilTrue(touchTarget, function (element) {
        return element.scrollWidth > element.clientWidth &&
               element.scrollWidth - element.clientWidth > element.scrollLeft;
    });

    scrollMap.bottom =conditionParentUntilTrue(touchTarget, function (element) {
        return element.scrollHeight > element.clientHeight &&
               element.scrollHeight - element.clientHeight > element.scrollTop;
    });

    touchScreenX = e.targetTouches[0].screenX;
    touchScreenY = e.targetTouches[0].screenY;
    disableScroll = false;
});

window.addEventListener('touchmove', function (e) {
    var moveScreenX,
        moveScreenY;

    if (disableScroll) {
        e.preventDefault();

        return;
    }

    moveScreenX = e.targetTouches[0].screenX;
    moveScreenY = e.targetTouches[0].screenY;

    if (
        moveScreenX > touchScreenX && scrollMap.left ||
        moveScreenY < touchScreenY && scrollMap.bottom ||
        moveScreenX < touchScreenX && scrollMap.right ||
        moveScreenY > touchScreenY && scrollMap.top
    ) {
        // You are scrolling either the element or its parent.
        // This will not affect document.body scroll.
    } else {
        // This will affect document.body scroll.

        e.preventDefault();

        disableScroll = true;
    }
});

The reason this works is that mobile Safari is using the first touch move to determine if the document body is being scrolled or the element (or either of the target element parents) and sticks to this decision.

How to get a .csv file into R?

Since you say you want to access by position once your data is read in, you should know about R's subsetting/ indexing functions.

The easiest is

df[row,column]
#example
df[1:5,] #rows 1:5, all columns
df[,5] #all rows, column 5. 

Other methods are here. I personally use the dplyr package for intuitive data manipulation (not by position).

How do I use the nohup command without getting nohup.out?

Following command will let you run something in the background without getting nohup.out:

nohup command |tee &

In this way, you will be able to get console output while running script on the remote server: enter image description here

Determine Pixel Length of String in Javascript/jQuery?

Put it in an absolutely-positioned div then use clientWidth to get the displayed width of the tag. You can even set the visibility to "hidden" to hide the div:

<div id="text" style="position:absolute;visibility:hidden" >This is some text</div>
<input type="button" onclick="getWidth()" value="Go" />
<script type="text/javascript" >
    function getWidth() {
        var width = document.getElementById("text").clientWidth;
        alert(" Width :"+  width);
    }
</script>

Python glob multiple filetypes

From previous answer

glob('*.jpg') + glob('*.png')

Here is a shorter one,

from glob import glob
extensions = ['jpg', 'png'] # to find these filename extensions

# Method 1: loop one by one and extend to the output list
output = []
[output.extend(glob(f'*.{name}')) for name in extensions]
print(output)

# Method 2: even shorter
# loop filename extension to glob() it and flatten it to a list
output = [p for p2 in [glob(f'*.{name}') for name in extensions] for p in p2]
print(output)

How do I install boto?

  1. install pip: https://pip.pypa.io/en/latest/installing.html

  2. insatll boto: https://github.com/boto/boto

    $ git clone git://github.com/boto/boto.git
    $ cd boto
    $ python setup.py install

Color text in discord

Discord doesn't allow colored text. Though, currently, you have two options to "mimic" colored text.

Option #1 (Markdown code-blocks)

Discord supports Markdown and uses highlight.js to highlight code-blocks. Some programming languages have specific color outputs from highlight.js and can be used to mimic colored output.

To use code-blocks, send a normal message in this format (Which follows Markdown's standard format).

```language
message
```

Languages that currently reproduce nice colors: prolog (red/orange), css (yellow).

Option #2 (Embeds)

Discord now supports Embeds and Webhooks, which can be used to display colored blocks, they also support markdown. For documentation on how to use Embeds, please read your lib's documentation.

(Embed Cheat-sheet)
Embed Cheat-sheet

Sort list in C# with LINQ

I assume that you want them sorted by something else also, to get a consistent ordering between all items where AVC is the same. For example by name:

var sortedList = list.OrderBy(x => c.AVC).ThenBy(x => x.Name).ToList();

Setting Icon for wpf application (VS 08)

@742's answer works pretty well, but as outlined in the comments when running from the VS debugger the generic icon is still shown.

If you want to have your icon even when you're pressing F5, you can add in the Main Window:

<Window x:Class="myClass"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Icon="./Resources/Icon/myIcon.png">

where you indicate the path to your icon (the icon can be *.png, *.ico.)

(Note you will still need to set the Application Icon or it'll still be the default in Explorer).

SPAN vs DIV (inline-block)

As others have answered… div is a “block element” (now redefined as Flow Content) and span is an “inline element” (Phrasing Content). Yes, you may change the default presentation of these elements, but there is a difference between “flow” versus “block”, and “phrasing” versus “inline”.

An element classified as flow content can only be used where flow content is expected, and an element classified as phrasing content can be used where phrasing content is expected. Since all phrasing content is flow content, a phrasing element can also be used anywhere flow content is expected. The specs provide more detailed info.

All phrasing elements, such as strong and em, can only contain other phrasing elements: you can’t put a table inside a cite for instance. Most flow content such as div and li can contain all types of flow content (as well as phrasing content), but there are a few exceptions: p, pre, and th are examples of non-phrasing flow content (“block elements”) that can only contain phrasing content (“inline elements”). And of course there are the normal element restrictions such as dl and table only being allowed to contain certain elements.

While both div and p are non-phrasing flow content, the div can contain other flow content children (including more divs and ps). On the other hand, p may only contain phrasing content children. That means you can’t put a div inside a p, even though both are non-phrasing flow elements.

Now here’s the kicker. These semantic specifications are unrelated to how the element is displayed. Thus, if you have a div inside a span, you will get a validation error even if you have span {display: block;} and div {display: inline;} in your CSS.

PHP write file from input to txt

If you use file_put_contents you don't need to do a fopen -> fwrite -> fclose, the file_put_contents does all that for you. You should also check if the webserver has write rights in the directory where you are trying to write your "data.txt" file.

Depending on your PHP version (if it's old) you might not have the file_get/put_contents functions. Check your webserver log to see if any error appeared when you executed the script.

How to return a file using Web API?

Example with IHttpActionResult in ApiController.

[HttpGet]
[Route("file/{id}/")]
public IHttpActionResult GetFileForCustomer(int id)
{
    if (id == 0)
      return BadRequest();

    var file = GetFile(id);

    IHttpActionResult response;
    HttpResponseMessage responseMsg = new HttpResponseMessage(HttpStatusCode.OK);
    responseMsg.Content = new ByteArrayContent(file.SomeData);
    responseMsg.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
    responseMsg.Content.Headers.ContentDisposition.FileName = file.FileName;
    responseMsg.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
    response = ResponseMessage(responseMsg);
    return response;
}

If you don't want to download the PDF and use a browsers built in PDF viewer instead remove the following two lines:

responseMsg.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
responseMsg.Content.Headers.ContentDisposition.FileName = file.FileName;

Clearing all cookies with JavaScript

Here's a simple code to delete all cookies in JavaScript.

function deleteAllCookies(){
   var cookies = document.cookie.split(";");
   for (var i = 0; i < cookies.length; i++)
     deleteCookie(cookies[i].split("=")[0]);
}

function setCookie(name, value, expirydays) {
 var d = new Date();
 d.setTime(d.getTime() + (expirydays*24*60*60*1000));
 var expires = "expires="+ d.toUTCString();
 document.cookie = name + "=" + value + "; " + expires;
}

function deleteCookie(name){
  setCookie(name,"",-1);
}

Run the function deleteAllCookies() to clear all cookies.

What's the difference between git reset --mixed, --soft, and --hard?

You don't have to force yourself to remember differences between them. Think of how you actually made a commit.

  1. Make some changes.

  2. git add .

  3. git commit -m "I did Something"

Soft, Mixed and Hard is the way enabling you to give up the operations you did from 3 to 1.

  • Soft "pretended" to never see you have did git commit.
  • Mixed "pretended" to never see you have did git add .
  • Hard "pretended" to never see you have made file changes.

PHP code to convert a MySQL query to CSV

If you'd like the download to be offered as a download that can be opened directly in Excel, this may work for you: (copied from an old unreleased project of mine)

These functions setup the headers:

function setExcelContentType() {
    if(headers_sent())
        return false;

    header('Content-type: application/vnd.ms-excel');
    return true;
}

function setDownloadAsHeader($filename) {
    if(headers_sent())
        return false;

    header('Content-disposition: attachment; filename=' . $filename);
    return true;
}

This one sends a CSV to a stream using a mysql result

function csvFromResult($stream, $result, $showColumnHeaders = true) {
    if($showColumnHeaders) {
        $columnHeaders = array();
        $nfields = mysql_num_fields($result);
        for($i = 0; $i < $nfields; $i++) {
            $field = mysql_fetch_field($result, $i);
            $columnHeaders[] = $field->name;
        }
        fputcsv($stream, $columnHeaders);
    }

    $nrows = 0;
    while($row = mysql_fetch_row($result)) {
        fputcsv($stream, $row);
        $nrows++;
    }

    return $nrows;
}

This one uses the above function to write a CSV to a file, given by $filename

function csvFileFromResult($filename, $result, $showColumnHeaders = true) {
    $fp = fopen($filename, 'w');
    $rc = csvFromResult($fp, $result, $showColumnHeaders);
    fclose($fp);
    return $rc;
}

And this is where the magic happens ;)

function csvToExcelDownloadFromResult($result, $showColumnHeaders = true, $asFilename = 'data.csv') {
    setExcelContentType();
    setDownloadAsHeader($asFilename);
    return csvFileFromResult('php://output', $result, $showColumnHeaders);
}

For example:

$result = mysql_query("SELECT foo, bar, shazbot FROM baz WHERE boo = 'foo'");
csvToExcelDownloadFromResult($result);

Error in MySQL when setting default value for DATE or DATETIME

Config syntax issue

On some versions of MYSQL (tested 5.7.*) under *nix systems you should use this syntax:

[mysqld]

sql-mode="NO_BACKSLASH_ESCAPES,STRICT_TRANS_TABLE,NO_ENGINE_SUBSTITUTION"

These won't work:

dash no quotes

sql-mode=NO_ENGINE_SUBSTITUTION

underscore no quotes

sql_mode=NO_ENGINE_SUBSTITUTION

underscore and quotes

sql_mode="NO_ENGINE_SUBSTITUTION"

A more complete review of config values and sql-mode:

How to setup permanent Sql Mode flags

xcode library not found

If your library file is called libGoogleAnalytics.a you need to put -lGoogleAnalytics so make sure the .a file is named as you'd expect

How to add double quotes to a string that is inside a variable?

You could use &quot; instead of ". It will be displayed correctly by the browser.

AngularJS accessing DOM elements inside directive template

You could write a directive for this, which simply assigns the (jqLite) element to the scope using an attribute-given name.

Here is the directive:

app.directive("ngScopeElement", function () {
  var directiveDefinitionObject = {

    restrict: "A",

    compile: function compile(tElement, tAttrs, transclude) {
      return {
          pre: function preLink(scope, iElement, iAttrs, controller) {
            scope[iAttrs.ngScopeElement] = iElement;
          }
        };
    }
  };

  return directiveDefinitionObject;
});

Usage:

app.directive("myDirective", function() {
    return {
        template: '<div><ul ng-scope-element="list"><li ng-repeat="item in items"></ul></div>',
        link: function(scope, element, attrs) {
            scope.list[0] // scope.list is the jqlite element, 
                          // scope.list[0] is the native dom element
        }
    }
});

Some remarks:

  • Due to the compile and link order for nested directives you can only access scope.list from myDirectives postLink-Function, which you are very likely using anyway
  • ngScopeElement uses a preLink-function, so that directives nested within the element having ng-scope-element can already access scope.list
  • not sure how this behaves performance-wise