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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly

I have a dataframe with ~300K rows and ~40 columns. I want to find out if any rows contain null values - and put these 'null'-rows into a separate dataframe so that I could explore them easily. ...
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CSS3 Transparency + Gradient

...round-image: -webkit-gradient( linear, left top, left bottom, from(rgba(50,50,50,0.8)), to(rgba(80,80,80,0.2)), color-stop(.5,#333333) ); (src) /* mozilla example - FF3.6+ */ background-image: -moz-linear-gradient( rgba(255, 255, 255, 0.7) 0%, rgba(255, 255, 255, 0) 95% ); (src) Apparent...
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Simple C example of doing an HTTP POST and consuming the response

... +50 A message has a header part and a message body separated by a blank line. The blank line is ALWAYS needed even if there is no message...
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Vagrant reverse port forwarding?

...ROR -o IdentitiesOnly=yes -i ~/.vagrant.d/insecure_private_key vagrant@127.0.0.1 SSH supports forwarding ports in the direction you want with the -R guestport:host:hostport option. So, if you wanted to connect to port 12345 on the guest and have it forwarded to localhost:80, you would use this comm...
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Shortest distance between a point and a line segment

...at l2 = length_squared(v, w); // i.e. |w-v|^2 - avoid a sqrt if (l2 == 0.0) return distance(p, v); // v == w case // Consider the line extending the segment, parameterized as v + t (w - v). // We find projection of point p onto the line. // It falls where t = [(p-v) . (w-v)] / |w-v|^2 ...
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Formula to determine brightness of RGB color

... 20 Answers 20 Active ...
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Mapping two integers to one, in a unique and deterministic way

...sy to define a bijection f : Z -> N, like so: f(n) = n * 2 if n >= 0 f(n) = -n * 2 - 1 if n < 0 share | improve this answer | follow | ...
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How can I check if a string represents an int, without using try/except?

...t;> print RepresentsInt("+123") True >>> print RepresentsInt("10.0") False It's going to be WAY more code to exactly cover all the strings that Python considers integers. I say just be pythonic on this one. sh...
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Why `null >= 0 && null

...ncrements the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined . ...
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Pandas groupby: How to get a union of strings

..._csv(StringIO(data),sep='\s+') In [5]: df Out[5]: A B C 0 1 0.749065 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...