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How to check for null in Twig?
...
And to check if something is not null, simply do {% if var is not null %}
– J.-B. C.
Sep 6 '12 at 19:31
4...
Pandas groupby: How to get a union of strings
...065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When you apply your own function, there is not automatic exclusions of non-numeric columns...
Sending an HTTP POST request on iOS
... does the server detect my posts (the server does detect posts coming from android)
7 Answers
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Why is git prompting me for a post-pull merge commit message?
...cently, following any git pull , git has started spawning my text editor, and asking for a merge commit message. A commit message is already pre-filled, and I just have to save and close the window to complete the pull.
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When a 'blur' event occurs, how can I find out which element focus went *to*?
...work for focus changes caused by tabbing through fields with the keyboard, and does not work at all in Chrome or Safari. The big problem with using activeElement (except in IE) is that it is not consistently updated until after the blur event has been processed, and may have no valid value at all du...
Error: Cannot pull with rebase: You have unstaged changes
...if you wanted to keep them. After pulling, you would then do git stash pop and your changes would be reapplied.
git status also has how to get rid of changes depending on if the file is staged for commit or not.
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Back to previous page with header( “Location: ” ); in PHP
...['HTTP_REFERER']);
Note that this may not work with secure pages (HTTPS) and it's a pretty bad idea overall as the header can be hijacked, sending the user to some other destination. The header may not even be sent by the browser.
Ideally, you will want to either:
Append the return address to t...
Overwriting my local branch with remote branch [duplicate]
I have completely fubar'd my local branch, and would like to start over. The version on the server is correct.
4 Answers
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What does “yield break;” do in C#?
...t after the loop has completed all its cycles, the last line gets executed and you will see the message in your console app.
Or like this with yield break:
int i = 0;
while (true)
{
if (i < 5)
{
yield return i;
}
else
{
// note that i++ will not be executed a...
send mail from linux terminal in one line [closed]
I know there is the command mail in linux to send emails via command line. How can I send an simple email with one line from the terminal though?
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