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How do I delete rows in a data frame?
...s that you wanted to delete. However, at some later point, you go into the raw data and have a look around and reorder the data. Your row deletion code will now delete the wrong rows, and worse, you are unlikely to get any errors warning you that this has occurred.
Better strategy
A better strateg...
Logical operators (“and”, “or”) in DOS batch
... The 'or' condition you describe is slick and works great for a range of numbers, but what if I am comparing 2 independent values, and not a range? For example, if this file exists or filename == ""
– bakoyaro
Dec 14 '17 at 21:10
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How to import the class within the same directory or sub directory?
... What do you do if the module you're trying to import has no classes? Just raw functions? In python 2 all I had to do was 'import module'. Doesn't work in python 3, neither does 'import .module'
– Frikster
Sep 26 '16 at 4:23
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How can I check if an element exists in the visible DOM?
...he project I'm working on, I'm not able to use a library. Good-ol' fashion raw code only. I'm aware of that jQuery method, but it does not work on elements not wrapped in the jQuery container. For example, $('#elementId')[0].length would not produce the same result.
– Justin Bu...
The tilde operator in Python
... with s[len(s) - 2].
As for your other question, this can be useful for a range of bitwise hacks.
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Convert base64 string to ArrayBuffer
...lso called a binary string) which is a string containing characters in the range 0-255. If your string has characters outside that range, btoa will throw an error.
– GetFree
Nov 16 '19 at 10:13
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What's the best way to convert a number to a string in JavaScript? [closed]
...like this for simple convenience, over 1,000s of iterations it appears for raw speed there is an advantage for .toString()
See Performance tests here (not by me, but found when I went to write my own):
http://jsben.ch/#/ghQYR
Fastest based on the JSPerf test above: str = num.toString();
It should...
How to get Ruby / Homebrew / RVM to work on Yosemite?
...mand line tools for Xcode 6
Reinstall brew:
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
Once brew is installed, rvm will work:
rvm install ruby
Worked for me, yahoo!
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Windows recursive grep command-line
...r in set
[^class] Inverse class: any one character not in set
[x-y] Range: any characters within the specified range
\x Escape: literal use of metacharacter x
\<xyz Word position: beginning of word
xyz\> Word position: end of word
For full information on FINDSTR regul...
Create a date from day month and year with T-SQL
...st and simplest. And it does not throw an error when day values are out of range either. Altho depending on the circumstance, an error may be desired, so just be aware that this silences day and month values that are out of expected range.
– Shawn Kovac
May 7 '...