`%r` is not a valid placeholder in the `str.format()` formatting operations; it only works in [old-style `%` string formatting](https://docs.python.org/2/library/stdtypes.html#string-formatting). It indeed converts the object to a representation through the `repr()` function.

In `str.format()`, `!r` is the equivalent, but this also means that you can now use all the [format codes](https://docs.python.org/2/library/string.html#formatspec) for a string. Normally `str.format()` will call the `object.__format__()` method on the object itself, but by using `!r`, `repr(object).__format__()` is used instead.

There are also the `!s` and (in Python 3) `!a` converters; these apply the `str()` and [`ascii()`](https://docs.python.org/3/library/functions.html#ascii) functions first.

The `0` in front indicates what argument to the `str.format()` method will be used to fill that slot; positional argument `0` is `&quot;Hello&quot;` in your case. You could use *named* arguments too, and pass in objects as keyword arguments:

    &quot;{greeting!r:20}&quot;.format(greeting=&quot;Hello&quot;)  

Unless you are using Python 2.6, you can omit this as slots without indices or names are automatically numbered; the first `{}` is `0`, the second `{}` takes the second argument at index `1`, etc.

I have already searched and almost implemented max solution but it&#39;s not installing any app even though if I am creating just sample single view app.

&gt;**App installation failed**  
&gt;A valid provisioning profile for this executable was not found.

[![enter image description here][1]][1]

  [1]: http://i.stack.imgur.com/TU8NJ.png


Xcode 7: App installation failed: A valid provisioning profile for this executable was not found

I managed configure webpack to output CSS and JS into respective sub-directories, i.e. &lt;code&gt;public/asests/css&lt;/code&gt; and &lt;code&gt;public/assets/js&lt;/code&gt;. However, I don&#39;t know how to do the same for images and fonts.

In other words, I want to output images in &lt;code&gt;public/assets/images&lt;/code&gt; folder and fonts into &lt;code&gt;public/assets/fonts&lt;/code&gt; folder. 

Here&#39;s my webpack config file:

    var path = require(&#39;path&#39;);
    var ExtractCSS = require(&#39;extract-text-webpack-plugin&#39;);

    module.exports = {
        context: path.resolve(&#39;private/js&#39;),
        resolve: [&#39;&#39;, &#39;.js&#39;, &#39;.jsx&#39;, &#39;.es6&#39;, &#39;.json&#39;],
        entry: {
            homepage: &#39;./homepage&#39;
        },
        output: {
            path: path.resolve(&#39;public/assets&#39;),
            publicPath: &#39;/public/assets/&#39;,
            filename: &#39;js/[name].js&#39;
        },
        plugins: [
            new ExtractCSS(&#39;css/[name].css&#39;)
        ],
        devServer: {
            contentBase: &#39;public&#39;
        },
        module: {
            loaders: [
                {
                    test: /\.(es6|js|jsx)$/,
                    exclude: /node_modules/,
                    loader: &#39;babel-loader&#39;
                },
                {
                    test: /\.css$/,
                    exclude: /node_modules/,
                    loader: ExtractCSS.extract(&#39;style-loader&#39;, &#39;css-loader&#39;)
                },
                {
                    test: /\.less$/,
                    exclude: /node_modules/,
                    loader: ExtractCSS.extract(&#39;style-loader&#39;, &#39;css-loader!less-loader&#39;)
                },
                {
                    test: /\.(jpg|jpeg|gif|png|woff|woff2|eot|ttf|svg)$/,
                    exclude: /node_modules/,
                    loader: &#39;url-loader?limit=1024&#39;
                }
            ]
        }
    }

Configure webpack to output images/fonts in a separate subfolders

As the title states, what is the difference between these two flags? It seems they both convert the value to a string using repr()?
Also, in this line of code: 

    &quot;{0!r:20}&quot;.format(&quot;Hello&quot;)  
What does the 0 in front of the !r do?

What is the difference between !r and %r in Python?

As the title states, what is the difference between these two flags? It seems they both convert the value to a string using repr()?
Also, in this line of code:
<pre><code class="hljs language-lua">"{0!r:20}".format("Hello") 
</code></pre>
What does the 0 in front of the !r do?

I have a pandas data frame like this:

       Column1  Column2  Column3  Column4  Column5
     0    a        1        2        3        4
     1    a        3        4        5
     2    b        6        7        8
     3    c        7        7        

What I want to do now is getting a new dataframe containing Column1 and a new columnA. This columnA should contain all values from columns 2 -(to) n (where n is the number of columns from Column2 to the end of the row) like this:

      Column1  ColumnA
    0   a      1,2,3,4
    1   a      3,4,5
    2   b      6,7,8
    3   c      7,7
How could I best approach this issue? Any advice would be helpful. Thanks in advance!

Merge multiple column values into one column in python pandas

I have an image in PIL Image format. I need to convert it to byte array.

    img = Image.open(fh, mode=&#39;r&#39;)  
    roiImg = img.crop(box)

Now I need the `roiImg` as a byte array.

Convert PIL Image to byte array?

I am trying to debug a script which takes command line arguments as an input. Arguments are text files in the same directory. Script gets file names from sys.argv list. My problem is I cannot launch the script with arguments in pycharm.

I have tried to enter arguments into &quot;Script parameters&quot; field in &quot;Run&quot; &gt; &quot;Edit configuration&quot; menu like so:

    -s&#39;file1.txt&#39;, -s&#39;file2.txt&#39;

But it did not work. How do I launch my script with arguments?

P.S. I am on Ubuntu

Pycharm and sys.argv arguments

when using seaborn heatmap, is there a way to auto-adjust the font size for it to fit exactly inside the squares?
for example in: 

    sns.heatmap(corrmat, vmin=corrmat.values.min(), vmax=1, square=True, cmap=&quot;YlGnBu&quot;, 
            linewidths=0.1, annot=True, annot_kws={&quot;size&quot;:8})  

here the size is set in &quot;annot_kws&quot;. 

Auto adjust font size in seaborn heatmap

How can I define a class with ``await`` in the constructor or class body?

For example what I want:

&lt;!-- language: lang-py --&gt;

    import asyncio

    # some code


    class Foo(object):

        async def __init__(self, settings):
            self.settings = settings
            self.pool = await create_pool(dsn)

    foo = Foo(settings)
    # it raises:
    # TypeError: __init__() should return None, not &#39;coroutine&#39;

or example with class body attribute:

&lt;!-- language: lang-py --&gt;

    class Foo(object):

        self.pool = await create_pool(dsn)  # Sure it raises syntax Error

        def __init__(self, settings):
            self.settings = settings

    foo = Foo(settings)

My solution (But I would like to see a more elegant way)

&lt;!-- language: lang-py --&gt;

    class Foo(object):

        def __init__(self, settings):
            self.settings = settings

        async def init(self):
            self.pool = await create_pool(dsn)

    foo = Foo(settings)
    await foo.init()

How to set class attribute with await in __init__

I&#39;m trying to add some values from my database to a `[]string` in Go. Some of these are timestamps.

I get the error:

&gt; cannot use U.Created_date (type time.Time) as type string in array element

Can I convert `time.Time` to `string`?

    type UsersSession struct {
        Userid int
        Timestamp time.Time
        Created_date time.Time
    }

    type Users struct {
        Name string
        Email string
        Country string
        Created_date time.Time
        Id int
        Hash string
        IP string
    }

-

    var usersArray = [][]string{}

    rows, err := db.Query(&quot;SELECT u.id, u.hash, u.name, u.email, u.country, u.IP, u.created_date, us.timestamp, us.created_date FROM usersSession AS us LEFT JOIN users AS u ON u.id = us.userid WHERE us.timestamp + interval 30 minute &gt;= now()&quot;)

    U := Users{}
    US := UsersSession{}

    for rows.Next() {
        err = rows.Scan(&amp;U.Id, &amp;U.Hash, &amp;U.Name, &amp;U.Email, &amp;U.Country, &amp;U.IP, &amp;U.Created_date, &amp;US.Timestamp, &amp;US.Created_date)
        checkErr(err)

        userid_string := strconv.Itoa(U.Id)
        user := []string{userid_string, U.Hash, U.Name, U.Email, U.Country, U.IP, U.Created_date, US.Timestamp, US.Created_date}
        // -------------
        // ^ this is where the error occurs
        // cannot use U.Created_date (type time.Time) as type string in array element (for US.Created_date and US.Timestamp aswell)
        // -------------

        usersArray = append(usersArray, user)
        log.Print(&quot;usersArray: &quot;, usersArray)
    }


**EDIT**

I added the following. It works now, thanks.

    userCreatedDate := U.Created_date.Format(&quot;2006-01-02 15:04:05&quot;)
    userSessionCreatedDate := US.Created_date.Format(&quot;2006-01-02 15:04:05&quot;)
    userSessionTimestamp := US.Timestamp.Format(&quot;2006-01-02 15:04:05&quot;)

Convert time.Time to string

Python can multiply strings like so:

    Python 3.4.3 (default, Mar 26 2015, 22:03:40)
    [GCC 4.9.2] on linux
    Type &quot;help&quot;, &quot;copyright&quot;, &quot;credits&quot; or &quot;license&quot; for more information.
    &gt;&gt;&gt; x = &#39;my new text is this long&#39;
    &gt;&gt;&gt; y = &#39;#&#39; * len(x)
    &gt;&gt;&gt; y
    &#39;########################&#39;
    &gt;&gt;&gt;

Can Golang do the equivalent somehow?


Can Golang multiply strings like Python can?

I can convert `Vec&lt;String&gt;` to `Vec&lt;&amp;str&gt;` this way:

    let mut items = Vec::&lt;&amp;str&gt;::new();
    for item in &amp;another_items {
        items.push(item);
    }

Are there better alternatives?

How do I convert a Vec&lt;String&gt; to Vec&lt;&amp;str&gt;?

C# 6 brings compiler support for interpolated string literals with syntax:

    var person = new { Name = &quot;Bob&quot; };

    string s = $&quot;Hello, {person.Name}.&quot;;

This is great for short strings, but if you want to produce a longer string must it be specified on a single line?

With other kinds of strings you can:

        var multi1 = string.Format(@&quot;Height: {0}
    Width: {1}
    Background: {2}&quot;,
            height,
            width,
            background);

Or:

    var multi2 = string.Format(
        &quot;Height: {1}{0}&quot; +
        &quot;Width: {2}{0}&quot; +
        &quot;Background: {3}&quot;,
        Environment.NewLine,
        height,
        width,
        background);

I can&#39;t find a way to achieve this with string interpolation without having it all one one line:

    var multi3 = $&quot;Height: {height}{Environment.NewLine}Width: {width}{Environment.NewLine}Background: {background}&quot;;

I realise that in this case you could use `\r\n` in place of `Environment.NewLine` (less portable), or pull it out to a local, but there will be cases where you can&#39;t reduce it below one line without losing semantic strength.

Is it simply the case that string interpolation should not be used for long strings?

Should we just string using `StringBuilder` for longer strings?

    var multi4 = new StringBuilder()
        .AppendFormat(&quot;Width: {0}&quot;, width).AppendLine()
        .AppendFormat(&quot;Height: {0}&quot;, height).AppendLine()
        .AppendFormat(&quot;Background: {0}&quot;, background).AppendLine()
        .ToString();

Or is there something more elegant?

Multiline C# interpolated string literal

Am learning swift and am struck in converting the date String to NSDate to string. Am getting the date string in this format &quot;Thu, 22 Oct 2015 07:45:17 +0000&quot;. I need to show the date in the MM-dd-yyyy format. I tried the following code but, it returns &quot;null&quot;.

    let dateFormatter = NSDateFormatter()
    dateFormatter.dateFormat = &quot;MM-dd-yyyy&quot;
    dateFormatter.dateStyle = NSDateFormatterStyle.MediumStyle
    let dateObj = dateFormatter.dateFromString(dateString!)
    print(&quot;Dateobj: \(dateObj)&quot;)

Can anyone please help where am going wrong? Looking forward the help. Thanks in advance.            



How to convert string to date to string in Swift iOS?

I am new to Brackets.io and thought I saw a shortcut key to auto indent/format HTML, however I cannot find a shortcut. Is there a shortcut or add-on that will do this for me?

Brackets.io: Is there a way to auto indent / format &lt;html&gt;

How can I do this format with a Python 3.6 F-String?

    person = {&#39;name&#39;: &#39;Jenne&#39;, &#39;age&#39;: 23}

    print(&#39;My name {0[name]} and my age {1[age]}&#39;.format(person, person))
    print(&#39;My name {0} and my age {1}&#39;.format(person[&#39;name&#39;], person[&#39;age&#39;]))




How can I do a dictionary format with f-string in Python 3 .6?

I have a url that I need to send a request to using date variables. The https address takes the date variables. I&#39;d like to assign the dates to the address string using something like the formatting operator % in Python. Does R have a similar operator or do I need to rely on paste()?

    # Example variables
    year = &quot;2008&quot;
    mnth = &quot;1&quot;
    day = &quot;31&quot;

This is what I would do in Python 2.7:

    url = &quot;https:.../KBOS/%s/%s/%s/DailyHistory.html&quot; % (year, mnth, day)

Or using .format() in 3.+.

The only I&#39;d know to do in R seems verbose and relies on paste:

    url_start = &quot;https:.../KBOS/&quot;
    url_end = &quot;/DailyHistory.html&quot;
    paste(url_start, year, &quot;/&quot;, mnth, &quot;/&quot;, day, url_end) 

Is there a better way of doing this?

Is there a string formatting operator in R similar to Python&#39;s %?

I&#39;m using the [C++ Extension][1] for [VSCode][2] *(Visual Studio Code)*.

Currently, I have the setting `&quot;C_Cpp.clang_format_formatOnSave&quot;` set to `true`.

This format&#39;s my code when I save my C++ file. But the format results in curly braces on new lines rather than on the same line.

**Current C++ VSCode Formatted**

    for (int i = 0; i &lt; 10; i++)
    {
        // ...
    }

**What I Want C++ VSCode Formatted Code to Look Like**

    for (int i = 0; i &lt; 10; i++) {
        // ...
    }

I also have `editor.wrappingIndent` set to `&quot;same&quot;`.

**How can I make curly braces in C++ format on the same line in Visual Studio Code?**

  [1]: https://marketplace.visualstudio.com/items?itemName=ms-vscode.cpptools
  [2]: https://code.visualstudio.com/

Format Curly Braces on Same Line in C++ VSCode

In my project i&#39;m currently using `application.yml` for configuration. Spring Initializr generate `application.properties`? What are the Pro/Cons for each one?

application.yml vs application.properties for Spring Boot

I am learning to localise my app to Simplified Chinese. I am following [this tutorial][1] on how to do this.

Because the tutorial is based on Obj-C, formatted strings can be written like this:

    &quot;Yesterday you sold %@ apps&quot; = &quot;Ayer le vendi&amp;oacute; %@ aplicaciones&quot;;
&quot;You like?&quot; = &quot;~Es bueno?~&quot;;

But I am using Swift. And in Swift I don&#39;t think you can use `%@` to indicate that there is something to be placed there. We have string interpolation right?

My app is kind of related to maths. And I want to display which input(s) is used to compute the result in a detailed label of a table view cell. For example

    --------------
    1234.5678
    From x, y &lt;---- Here is the detailed label
    --------------

Here, `From x, y` means &quot;The result is computed from x and y&quot;. I want to translate this to Chinese:

    从 x, y 得出

Before, I can just use this:

    &quot;From \(someVariable)&quot;

with the strings file:

    &quot;From&quot; = &quot;从 得出&quot;;

And this is how I would use it in code

    &quot;\(NSLocalizedString(&quot;From&quot;, comment: &quot;&quot;)) \(someVariable)&quot;

But if this were used in the Chinese version, the final string will be like this:

    &quot;从 得出 x, y&quot;

I mean I can put the `从` and `得出` in two different entries in the strings file. But is there a better way to do it?


  [1]: http://www.raywenderlich.com/64401/internationalization-tutorial-for-ios-2014

How to format localised strings in Swift?

I&#39;m trying out Python 3.6. Going through new code, I stumbled upon this new syntax:

    f&quot;My formatting string!&quot;

It seems we can do things like this:

    &gt;&gt;&gt; name = &quot;George&quot;
    &gt;&gt;&gt; print(f&quot;My cool string is called {name}.&quot;)
    My cool string is called George.

Can anyone shed some light on the inner workings of this? In particular what is the scope of the variables that an f-prefixed string can take?

    

String with &#39;f&#39; prefix in python-3.6

This is what I know

    str = String.Format(&quot;Her name is {0} and she&#39;s {1} years old&quot;, &quot;Lisa&quot;, &quot;10&quot;);

But I want something like

    str = String(&quot;Her name is @name and she&#39;s @age years old&quot;);
    str.addParameter(@name, &quot;Lisa&quot;);
    str.addParameter(@age, 10);

Is there a &quot;String.Format&quot; that can accept named input parameters instead of index placeholders?

I&#39;m trying to write a small script that will automate some PHP boilerplate that I need to write. It should write a copy of the string `code` to the output file with the various replacement fields filled in for each dict in the `fields` list.

However, I&#39;m getting the error:

    Traceback (most recent call last):
        File &quot;writefields.py&quot;, line 43, in &lt;module&gt;
            formatted = code.format(**field)
    ValueError: unexpected &#39;{&#39; in field name
As far as I can tell, there are no extra braces in either the replacement fields or the dicts that should be causing issues, so any help would be appreciated.

    code = &#39;&#39;&#39;
    // {label}
    add_filter( &#39;submit_job_form_fields&#39;, &#39;frontend_add_{fieldname}_field&#39; );
    function frontend_add_{fieldname}_field($fields) {
    	$fields[&#39;job&#39;][&#39;job_{fieldname}&#39;] = array(
    		&#39;label&#39; =&gt; __(&#39;{label}&#39;, &#39;job_manager&#39;),
    		&#39;type&#39; =&gt; &#39;text&#39;,
    		&#39;required&#39; =&gt; {required},
    		&#39;priority&#39; =&gt; 7,
    		&#39;placeholder&#39; =&gt; &#39;{placeholder}&#39;
    	);
    	return $fields;
    }
    add_filter( &#39;job_manager_job_listing_data_fields&#39;, &#39;admin_add_{fieldname}_field&#39; );
    function admin_add_{fieldname}_field( $fields ) {
      $fields[&#39;_job_{fieldname}&#39;] = array(
        &#39;label&#39;       =&gt; __( &#39;{label}&#39;, &#39;job_manager&#39; ),
        &#39;type&#39;        =&gt; &#39;text&#39;,
        &#39;placeholder&#39; =&gt; &#39;{placeholder}&#39;,
        &#39;description&#39; =&gt; &#39;&#39;
      );
      return $fields;
    }
    &#39;&#39;&#39;
    
    fields = [
    	{
    		&#39;fieldname&#39;: &#39;salary&#39;,
    		&#39;label&#39;: &#39;Salary ($)&#39;,
    		&#39;required&#39;: &#39;true&#39;,
    		&#39;placeholder&#39;: &#39;e.g. 20000&#39;,
    	},
    	{
    		&#39;fieldname&#39;: &#39;test&#39;,
    		&#39;label&#39;: &#39;Test Field&#39;,
    		&#39;required&#39;: &#39;true&#39;,
    		&#39;placeholder&#39;: &#39;&#39;,
    	}
    ]
    
    with open(&#39;field-out.txt&#39;, &#39;w&#39;) as f:
    	for field in fields:
    		formatted = code.format(**field)
    		f.write(formatted)
    		f.write(&#39;\n&#39;)

Unexpected &#39;{&#39; in field name when doing string formatting

Thanks to [David Beazley&#39;s tweet][1], I&#39;ve recently found out that the new [Python 3.6 f-strings][2] can also be nested:

    &gt;&gt;&gt; price = 478.23
    &gt;&gt;&gt; f&quot;{f&#39;${price:0.2f}&#39;:*&gt;20s}&quot;
    &#39;*************$478.23&#39;

Or:

    &gt;&gt;&gt; x = 42
    &gt;&gt;&gt; f&#39;&#39;&#39;-{f&quot;&quot;&quot;*{f&quot;+{f&#39;.{x}.&#39;}+&quot;}*&quot;&quot;&quot;}-&#39;&#39;&#39;
    &#39;-*+.42.+*-&#39;

While I am surprised that this is possible, I am missing on how practical is that, when would nesting f-strings be useful? What use cases can this cover?

Note: The PEP itself does not mention nesting f-strings, but there is a [specific test case][3].


  [1]: https://twitter.com/dabeaz/status/810217326293479425?lang=en
  [2]: https://www.python.org/dev/peps/pep-0536/
  [3]: https://github.com/python/cpython/blob/master/Lib/test/test_fstring.py#L536

Content Type	Original Author	Original Content on Stackoverflow
Question	b_pcakes	View Question on Stackoverflow
Solution 1 - Python	Martijn Pieters	View Answer on Stackoverflow

What is the difference between !r and %r in Python?

Python Problem Overview

Python Solutions

Solution 1 - Python

Configure webpack to output images/fonts in a separate subfolders

Xcode 7: App installation failed: A valid provisioning profile for this executable was not found

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