Use [`datetime.datetime.fromtimestamp`][1]:

    &gt;&gt;&gt; import datetime
    &gt;&gt;&gt; s = 1236472051807 / 1000.0
    &gt;&gt;&gt; datetime.datetime.fromtimestamp(s).strftime(&#39;%Y-%m-%d %H:%M:%S.%f&#39;)
    &#39;2009-03-08 09:27:31.807000&#39;

`%f` directive is only supported by [`datetime.datetime.strftime`][2], not by [`time.strftime`][3].


**UPDATE** Alternative using [`%`][4], [`str.format`][5]:

    &gt;&gt;&gt; import time
    &gt;&gt;&gt; s, ms = divmod(1236472051807, 1000)  # (1236472051, 807)
    &gt;&gt;&gt; &#39;%s.%03d&#39; % (time.strftime(&#39;%Y-%m-%d %H:%M:%S&#39;, time.gmtime(s)), ms)
    &#39;2009-03-08 00:27:31.807&#39;
    &gt;&gt;&gt; &#39;{}.{:03d}&#39;.format(time.strftime(&#39;%Y-%m-%d %H:%M:%S&#39;, time.gmtime(s)), ms)
    &#39;2009-03-08 00:27:31.807&#39;


  [1]: http://docs.python.org/2/library/datetime.html#datetime.datetime.fromtimestamp
  [2]: http://docs.python.org/2/library/datetime.html#datetime.datetime.strftime
  [3]: http://docs.python.org/2/library/time.html#time.strftime
  [4]: http://docs.python.org/2/library/stdtypes.html#string-formatting-operations
  [5]: http://docs.python.org/2/library/stdtypes.html#str.format

those are miliseconds, just divide them by 1000, since gmtime expects seconds ...

    time.strftime(&#39;%Y-%m-%d %H:%M:%S&#39;, time.gmtime(1236472051807/1000.0))

I&#39;m a pendulum fan... so...

```python
import pendulum
pendulum.from_timestamp(1236472051807/1000.0,tz=&#39;America/Toronto&#39;)
```

outputs:

&gt; `DateTime(2019, 12, 20, 10, 55, 10, tzinfo=Timezone(&#39;America/Toronto&#39;))`

For all the searches looking for `internalDate` for the Gmail API... the above is what works for me and is more accurate than the `Date` header.

I have the following CATransition for a UIView called `finalScoreView`, which makes it enter the screen from the top:

    CATransition *animation = [CATransition animation];
    animation.duration = 0.2;
    animation.type = kCATransitionPush;
    animation.subtype = kCATransitionFromBottom;
    animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
    
    [gameOver.layer addAnimation:animation forKey:@&quot;changeTextTransition&quot;];
    [finalScoreView.layer addAnimation:animation forKey:@&quot;changeTextTransition&quot;];

How do I make it so it bounces once after it comes down, then stays still?  It should still enter the screen from the top but then bounce when it comes down.

Any help would be much appreciated, thanks!

How to create a UIView bounce animation?

This bothers me for my whole IT life - I worked with 7 different versions of Excel over 20 years now, with big changes in each version, forcing me to search where the old features are hidden in the new version - but one single thing stays solid as a rock: the disability to open two files with the same name.

&gt; Sorry, Excel can&#39;t open two workbooks with the same name at the same time.

So I&#39;m really longing for an insight here, why this is still the case in Excel 2013, which was not even necessary to implement in Excel 95? Is there any technical or design reason within the Excel data structures or internal processings that it can&#39;t handle two File objects with diffenrent paths but the same file name? I don&#39;t want no Microsoft bashing here, I just want to understand the reason behind it.


Why on earth can&#39;t Excel handle 2 files with the same name?

I have used a ruby script to convert iso time stamp to epoch, the files that I am parsing has following time stamp structure: 

    2009-03-08T00:27:31.807

Since I want to keep milliseconds I used following ruby code to convert it to epoch time: 

    irb(main):010:0&gt; DateTime.parse(&#39;2009-03-08T00:27:31.807&#39;).strftime(&quot;%Q&quot;)
    =&gt; &quot;1236472051807&quot;

But In python I tried following: 

    import time 
    time.strftime(&#39;%Y-%m-%d %H:%M:%S&#39;, time.gmtime(1236472051807))

But I don&#39;t get the original time date time back, 

    &gt;&gt;&gt; time.strftime(&#39;%Y-%m-%d %H:%M:%S&#39;, time.gmtime(1236472051807))
    &#39;41152-03-29 02:50:07&#39;
    &gt;&gt;&gt; 

I wonder is it related to how I am formatting? 

Converting epoch time with milliseconds to datetime

I have used a ruby script to convert iso time stamp to epoch, the files that I am parsing has following time stamp structure:
<pre><code class="hljs language-makefile">2009-03-08T00:27:31.807
</code></pre>
Since I want to keep milliseconds I used following ruby code to convert it to epoch time:
<pre><code class="hljs language-ruby">irb(main):010:0> DateTime.parse('2009-03-08T00:27:31.807').strftime("%Q")
=> "1236472051807"
</code></pre>
But In python I tried following:
<pre><code class="hljs language-lua">import time 
time.strftime('%Y-%m-%d %H:%M:%S', time.gmtime(1236472051807))
</code></pre>
But I don't get the original time date time back,
<pre><code class="hljs language-python-repl">>>> time.strftime('%Y-%m-%d %H:%M:%S', time.gmtime(1236472051807))
'41152-03-29 02:50:07'
>>> 
</code></pre>
I wonder is it related to how I am formatting?

I am working on Scrapy 0.20 with Python 2.7. I found PyCharm has a good Python debugger. I want to test my Scrapy spiders using it. Anyone knows how to do that please?

&lt;h3&gt; What I have tried&lt;/h3&gt;
Actually I tried to run the spider as a script. As a result, I built that script. Then, I tried to add my Scrapy project to PyCharm as a model like this:

    File-&gt;Setting-&gt;Project structure-&gt;Add content root.

But I don&#39;t know what else I have to do

How to use PyCharm to debug Scrapy projects

Given a DataFrame with a column &quot;BoolCol&quot;, we want to find the indexes of the DataFrame in which the values for &quot;BoolCol&quot; == True

I currently have the iterating way to do it, which works perfectly:

    for i in range(100,3000):
        if df.iloc[i][&#39;BoolCol&#39;]== True:
             print i,df.iloc[i][&#39;BoolCol&#39;]

But this is not the correct panda&#39;s way to do it.
After some research, I am currently using this code:

    df[df[&#39;BoolCol&#39;] == True].index.tolist()

This one gives me a list of indexes, but they dont match, when I check them by doing:

    df.iloc[i][&#39;BoolCol&#39;]

The result is actually False!!

Which would be the correct Pandas way to do this?


Python Pandas: Get index of rows which column matches certain value

I&#39;m using opencv 2.4.2, python 2.7
The following simple code created a window of the correct name, but its content is just blank and doesn&#39;t show the image:

    import cv2
    img=cv2.imread(&#39;C:/Python27/03323_HD.jpg&#39;)
    cv2.imshow(&#39;ImageWindow&#39;,img)

does anyone knows about this issue?

cv2.imshow command doesn&#39;t work properly in opencv-python

What&#39;s the difference between a namespace Python package (no ``__init__.py``) and a regular Python package (has an ``__init__.py``), especially when ``__init__.py`` is empty for a regular package?

I am curious because recently I&#39;ve been forgetting to make ``__init__.py`` in packages I make, and I never noticed any problems.  In fact, they seem to behave identically to regular packages.

Edit: Namespace packages only supported from Python 3.3 ([see PEP 420](http://legacy.python.org/dev/peps/pep-0420/)), so naturally, this question only applies to Python 3.

Namespace vs regular package

    
I can&#39;t figure out the difference between Pandas `.aggregate` and `.apply` functions.    
Take the following as an example: I load a dataset, do a `groupby`, define a simple function,
and either user `.agg` or `.apply`.

As you may see, the printing statement within my function results in the same output
after using `.agg` and `.apply`. The result, on the other hand is different. Why is that?
    
    import pandas
    import pandas as pd
    iris = pd.read_csv(&#39;iris.csv&#39;)
    by_species = iris.groupby(&#39;Species&#39;)
    def f(x):
        ...:     print type(x)
        ...:     print x.head(3)
        ...:     return 1


Using `apply`:


    by_species.apply(f)
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #   Sepal.Length  Sepal.Width  Petal.Length  Petal.Width Species
    #0           5.1          3.5           1.4          0.2  setosa
    #1           4.9          3.0           1.4          0.2  setosa
    #2           4.7          3.2           1.3          0.2  setosa
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #   Sepal.Length  Sepal.Width  Petal.Length  Petal.Width Species
    #0           5.1          3.5           1.4          0.2  setosa
    #1           4.9          3.0           1.4          0.2  setosa
    #2           4.7          3.2           1.3          0.2  setosa
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #    Sepal.Length  Sepal.Width  Petal.Length  Petal.Width     Species
    #50           7.0          3.2           4.7          1.4  versicolor
    #51           6.4          3.2           4.5          1.5  versicolor
    #52           6.9          3.1           4.9          1.5  versicolor
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #     Sepal.Length  Sepal.Width  Petal.Length  Petal.Width    Species
    #100           6.3          3.3           6.0          2.5  virginica
    #101           5.8          2.7           5.1          1.9  virginica
    #102           7.1          3.0           5.9          2.1  virginica
    #Out[33]: 
    #Species
    #setosa        1
    #versicolor    1
    #virginica     1
    #dtype: int64

Using `agg`    
    
    by_species.agg(f)
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #   Sepal.Length  Sepal.Width  Petal.Length  Petal.Width Species
    #0           5.1          3.5           1.4          0.2  setosa
    #1           4.9          3.0           1.4          0.2  setosa
    #2           4.7          3.2           1.3          0.2  setosa
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #    Sepal.Length  Sepal.Width  Petal.Length  Petal.Width     Species
    #50           7.0          3.2           4.7          1.4  versicolor
    #51           6.4          3.2           4.5          1.5  versicolor
    #52           6.9          3.1           4.9          1.5  versicolor
    #&lt;class &#39;pandas.core.frame.DataFrame&#39;&gt;
    #     Sepal.Length  Sepal.Width  Petal.Length  Petal.Width    Species
    #100           6.3          3.3           6.0          2.5  virginica
    #101           5.8          2.7           5.1          1.9  virginica
    #102           7.1          3.0           5.9          2.1  virginica
    #Out[34]: 
    #           Sepal.Length  Sepal.Width  Petal.Length  Petal.Width
    #Species                                                         
    #setosa                 1            1             1            1
    #versicolor             1            1             1            1
    #virginica              1            1             1            1




What is the difference between pandas agg and apply function?

I&#39;m trying to overwrite a getter method for an ActiveRecord model. I have an attribute called `name` in the model `Category`, and I&#39;d like to be able to do something like this:

    def name
      name_trans || name
    end

If `name_trans` attribute is not nil, then return it, else return `name` attribute. How would I do this?

This should then be called normally like this:

    @category.name


How can I overwrite a getter method in an ActiveRecord model?

I&#39;m getting this error when I try to upload using paperclip with my rails blogging app.
Not sure what it is referring to when it says &quot;MissingRequiredValidatorError&quot;
I thought that by updating post_params and giving it :image it would be fine, as both create and update use post_params

    Paperclip::Errors::MissingRequiredValidatorError in PostsController#create
    Paperclip::Errors::MissingRequiredValidatorError

    Extracted source (around line #30):

    def create
      @post = Post.new(post_params)


This is my posts_controller.rb      

    def update
      @post = Post.find(params[:id])
   
      if @post.update(post_params)
        redirect_to action: :show, id: @post.id
      else
        render &#39;edit&#39;
      end
    end

    def new
      @post = Post.new
    end
      
    def create
      @post = Post.new(post_params)
   
      if @post.save
        redirect_to action: :show, id: @post.id
      else
        render &#39;new&#39;
      end
    end
    #...

    private
   
    def post_params
      params.require(:post).permit(:title, :text, :image)
    end    
       

and this is my posts helper 


    module PostsHelper
      def post_params
        params.require(:post).permit(:title, :body, :tag_list, :image)
      end
    end

Please let me know if I can supplement extra material to help you help me.


Paperclip::Errors::MissingRequiredValidatorError with Rails 4

There is the following code:

    def index
    	@car_types = car_brand.car_types
    end
    
    def car_brand
    	CarBrand.find(params[:car_brand_id])
    	rescue ActiveRecord::RecordNotFound
    		raise Errors::CarBrandNotFound.new 
    end

I want to test it through RSpec. My code is:

    it &#39;raises CarBrandNotFound exception&#39; do
    	get :index, car_brand_id: 0
    	expect(response).to raise_error(Errors::CarBrandNotFound)
    end

CarBrand with id equaling 0 doesn&#39;t exist, therefore my controller code raises Errors::CarBrandNotFound, but my test code tells me that nothing was raised. How can I fix it? What do I wrong? 

How to test exception raising in Rails/RSpec?

I&#39;m new-ish to Ruby and Rails.  I am looking for a purely objective list of features and advantages/disadvantages of each.  In an effort to keep preference out of this, please refrain from answering unless you have used all 3 systems. 

What are the differences between rbenv, rvm, and chruby?

I am posting a date to an API and the required format is as follows:

    2014-12-01T01:29:18

I can get the date from the model like so:

    Model.created_at.to_s

That returns:

    2014-12-01 01:29:18 -0500

How can I use Rails or Ruby to format it like the required format with the T and removing the -0500?

Rails formatting date

As I was looking into solutions for another question, I found myself wondering whether it was possible to use .NET&#39;s [`Calendar`](http://msdn.microsoft.com/en-us/library/system.globalization.calendar%28v=vs.110%29.aspx) class to implement a calendar that wasn&#39;t based on Earthly conventions.

For instance, [Mars&#39; day](http://en.wikipedia.org/wiki/Timekeeping_on_Mars) is about 2.7% longer than a day here on Earth:
&gt; A convention used by spacecraft lander projects to date has been to keep track of local solar time using a 24 hour &quot;Mars clock&quot; on which the hours, minutes and seconds are 2.7% longer than their standard (Earth) durations.

Is there any good way to implement a `MarsCalendar` such that the length of a second is different from the standard `GregorianCalendar`, and thus be able to use `DateTime` objects based on it for all the standard `AddDays()`, `AddHours()`, etc. functions?  &lt;sub&gt;(Note: Ideally, a solution - if one exists - would be applicable to any form of planetary object for which it is possible to define both &quot;1 day&quot; and &quot;1 year&quot; of consistent lengths. Mars makes for a great example, though)&lt;/sub&gt;

Implementing a non-terrestrial calendar

I have a Pandas `DataFrame` indexed by date. There a number of columns but many columns are only populated for part of the time series. I&#39;d like to find where the first and last values non-`NaN` values are located so that I can extracts the dates and see how long the time series is for a particular column.

Could somebody point me in the right direction as to how I could go about doing something like this? Thanks in advance.

Locate first and last non NaN values in a Pandas DataFrame

Java 8 added a new [*java.time*][1] API for working with dates and times ([JSR 310][2]).

I have date and time as string (e.g. `&quot;2014-04-08 12:30&quot;`). How can I obtain a [`LocalDateTime`][3] instance from the given string?

After I finished working with the `LocalDateTime` object: How can I then convert the `LocalDateTime` instance back to a string with the same format as shown above?


  [1]: https://docs.oracle.com/javase/8/docs/api/java/time/package-summary.html
  [2]: https://jcp.org/en/jsr/detail?id=310
  [3]: https://docs.oracle.com/javase/8/docs/api/java/time/LocalDateTime.html

How to parse/format dates with LocalDateTime? (Java 8)

I have a table TEST with a `DATETIME` field, like this:

```lang-none
ID NAME DATE
1 TESTING 2014-03-19 20:05:20.000
```

What I need a query returning this row and every row with date 03/19/2014, no matter what the time is. I tried using

```lang-sql
select * from test where date = &#39;03/19/2014&#39;;
```

But it returns no rows. The only way to make it work that I found is to also provide the time portion of the date:

```lang-sql
select * from test where date = &#39;03/19/2014 20:03:02.000&#39;;
```

How to query DATETIME field using only date in Microsoft SQL Server?

I&#39;m trying to pass a UTC date as a query string parameter to a Web API method. The URL looks like 

    /api/order?endDate=2014-04-01T00:00:00Z&amp;zoneId=4

The signature of the method looks like

    [HttpGet]
    public object Index(int zoneId, DateTime? endDate = null)

The date is coming in as `31/03/2014 8:00:00 PM` but I&#39;d like it to come in as `01/04/2014 12:00:00 AM`

My `JsonFormatter.SerializerSettings` looks like this

    new JsonSerializerSettings
    {
        ContractResolver = new CamelCasePropertyNamesContractResolver(),
        DateTimeZoneHandling = DateTimeZoneHandling.Utc,
        DateFormatHandling = DateFormatHandling.IsoDateFormat
    };

EDIT #1:
I&#39;ve noticed when I POST `2014-04-01T00:00:00Z` it will serialize to the UTC DateTime kind in C#. However I&#39;ve found a work around of doing `endDate.Value.ToUniversalTime()` to convert it although I find it odd how it works for a POST but not a GET.

Passing UTC DateTime to Web API HttpGet Method results in local time

How do I extract the epoch value to `Long` from instances of `LocalDateTime` or `LocalDate`? I&#39;ve tried 
the following, but it gives me other results:

    LocalDateTime time = LocalDateTime.parse(&quot;04.02.2014  19:51:01&quot;, DateTimeFormatter.ofPattern(&quot;dd.MM.yyyy  HH:mm:ss&quot;));
    System.out.println(time.getLong(ChronoField.SECOND_OF_DAY)); // gives 71461
    System.out.println(time.getLong(ChronoField.EPOCH_DAY)); // gives 16105
What I want is simply the value `1391539861` for the local datetime `&quot;04.02.2014  19:51:01&quot;`.
My timezone is `Europe/Oslo` UTC+1 with daylight saving time.

How to extract epoch from LocalDate and LocalDateTime?

Java 8&#39;s `LocalDateTime` has an `ofEpochSecond` method. Unfortunately, there is no such method in the `ZonedDateTime`. Now, I have an Epoch value and an explicit `ZoneId` given. How do I get a `ZonedDateTime` out of these?

Java 8: How to create a ZonedDateTime from an Epoch value?

I have a sheet with a column of unix epoch times (in seconds): 1500598288

How can I convert these into normal dates?

Content Type	Original Author	Original Content on Stackoverflow
Question	add-semi-colons	View Question on Stackoverflow
Solution 1 - Python	falsetru	View Answer on Stackoverflow
Solution 2 - Python	Joran Beasley	View Answer on Stackoverflow
Solution 3 - Python	rjmoggach	View Answer on Stackoverflow

Converting epoch time with milliseconds to datetime

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Why on earth can't Excel handle 2 files with the same name?

How to create a UIView bounce animation?

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