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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
Facebook API “This app is in development mode”
...s%3A%2F%2Fdevelopers.facebook.com%2Fdocs%2Ffacebook-login%2Fios
STEP 2
Select your application
STEP 3
Click the app Review tab.
Change switch value no to yes. See picture below.
After this your app is live.
sha...
How to append a newline to StringBuilder
... edited Mar 15 '19 at 16:20
Charles Giguere
4711 silver badge99 bronze badges
answered Dec 3 '15 at 18:00
...
What is the difference between localStorage, sessionStorage, session and cookies?
...e Mozilla source code we can see that 5120KB (5MB which equals 2.5 Million chars on Chrome) is the default storage size for an entire domain. This gives you considerably more space to work with than a typical 4KB cookie.
The data is not sent back to the server for every HTTP request (HTML, images, J...
What is the in a .vimrc file?
...or example, if you find yourself frequently deleting exactly 3 words and 7 characters, you might find it convenient to map a command via nmap <leader>d 3dw7x so that pressing the leader key followed by d will delete 3 words and 7 characters. Because it uses the leader key as a prefix, you can ...
How to do a join in linq to sql with method syntax?
...eOtherClass
on sc.Property1 equals soc.Property2
select new { SomeClass = sc, SomeOtherClass = soc };
Would be equivalent to:
var result = enumerableOfSomeClass
.Join(enumerableOfSomeOtherClass,
sc => sc.Property1,
soc => soc.Property2,
...
Add 2 hours to current time in MySQL?
...
SELECT *
FROM courses
WHERE DATE_ADD(NOW(), INTERVAL 2 HOUR) > start_time
See Date and Time Functions for other date/time manipulation.
share
...
MySQL CONCAT returns NULL if any field contain NULL
...
convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
...
Input placeholders for Internet Explorer
...n(){
if (input.val() === text) input.css({ color:'lightGrey' }).selectRange(0,0).one('keydown', function(){
input.val("").css({ color:'black' });
});
});
input.blur(function(){
if (input.val() == "" || input.val() === text) input.val(text)...
What does extern inline do?
..., ## s);
//=========== MACRO MAGIC ENDS ============
int main (int argc, char** argv) {
LOG("Greetings StackOverflow! - from enthusiasticgeek\n");
return 0;
}
For multiple files define these macros in a separate header file including the same in each c/cc/cxx/cpp files. Please prefer inlin...