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Why isn't my Pandas 'apply' function referencing multiple columns working? [closed]

...[44]: df Out[44]: a b c Value 0 -1.674308 foo 0.343801 0.044698 1 -2.163236 bar -2.046438 -0.116798 2 -0.199115 foo -0.458050 -0.199115 3 0.918646 bar -0.007185 -0.001006 4 1.336830 foo 0.534292 0.268245 ...
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Rails: call another controller action from a controller

I need to call the create action in controller A, from controller B. 9 Answers 9 ...
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Grep characters before and after match?

... characters after $> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}' 23_string_and share | improve this answer | follow | ...
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Compare floats in php

...ou need to use a smallest acceptable difference: if (abs(($a-$b)/$b) < 0.00001) { echo "same"; } Something like that. share | improve this answer | follow ...
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How to check if an int is a null

... An int is not null, it may be 0 if not initialized. If you want an integer to be able to be null, you need to use Integer instead of int. Integer id; String name; public Integer getId() { return id; } Besides the statement if(person.equals(null)) can...
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Why is there a `null` value in JavaScript?

... @EricElliott: typeof lies - read the spec or try returning null from a constructor – Christoph Apr 13 '13 at 11:59 5 ...
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Get Substring - everything before certain char

...exOf(stopAt, StringComparison.Ordinal); if (charLocation > 0) { return text.Substring(0, charLocation); } } return String.Empty; } } Results: 223232 443 34443553 344 34 ...
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What programming practice that you once liked have you since changed your mind about? [closed]

...once kept me awake and in a glorious programming mood, where the code flew from my fingers with feverous fluidity. Now it does nothing, and if I don't have it I get a headache. share ...
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CSS to set A4 paper size

... the width of ~196mm and then scale the whole content up to the width of 210mm ~ but strangely exactly the same scaling factor is applied to contents with any width smaller than 210mm). To fix this problem you can simply in the print media rule assign the A4 paper width and hight to html, body or di...
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PHP mail function doesn't complete sending of e-mail

...traced at the server maillogs (the location of server of mail log can vary from server to server, as explained above). In case you are on a shared hosting server, the ports 25 and 587 remain blocked by default. This block is been purposely done by your hosting provider. This is true even for some of...