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Create an empty data.frame
... Nice solution, however I found that I get a data frame with 0 rows. In order to keep the size of the data frame the same, I suggest new_df = df[NA,]. This also allows to store any previous column into the new data frame. For example to obtain the "Date" column from original df (while keeping res...
Block Declaration Syntax List
...at this is distinct from "Blocks as Parameters"; in this instance, you're calling a method that wants a block argument with an anonymous block. If you have already declared a block variable, it is sufficient to pass the variable name as the argument.
[someObject doSomethingWithBlock: ^return_type (...
How to change root logging level programmatically for logback
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How to make a background 20% transparent on Android
...way, instead of CC use 33 which is the hexadecimal for 255 * 0.2 = 51.
In order to calculate the proper value for an alpha transparency value you can follow this procedure:
Given a transparency percentage, for example 20%, you know the opaque percentage value is 80% (this is 100-20=80)
The range ...
How to check for valid email address? [duplicate]
...ere is no point. Even if you can verify that the email address is syntactically valid, you'll still need to check that it was not mistyped, and that it actually goes to the person you think it does. The only way to do that is to send them an email and have them click a link to verify.
Therefore, a ...
Large, persistent DataFrame in pandas
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Why use iterators instead of array indices?
...t the stream iterators and think about what == has been perverted to do in order to fit the pattern, and then tell me iterators are not broken! Or for linked lists. Even for arrays, having to specify one past the end is a broken C style idea -- pointer into the never never. They should be like Ja...
How to Decrease Image Brightness in CSS
...ond, Firefox jumped straight into non-prefixed filter, third, you have the order wrong, non-prefixed should be the last one, fourth, syntax for IE's -ms-filter is different (progid:DXImageTransform, etc), fifth, syntax for Firefox is different and requires SVG ( See docs ), sixth, new features aren'...
How to grant permission to users for a directory using command line in Windows?
...21) -
User astark recommends replacing Everyone with the term *S-1-1-0 in order for the command to be language independent. I only have an English install of Windows, so I can't test this proposal, but it seems reasonable.
Initial size for the ArrayList
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if you want to use Collections.fill(list, obj); in order to fill the list with a repeated object alternatively you can use
ArrayList<Integer> arr=new ArrayList<Integer>(Collections.nCopies(10, 0));
the line copies 10 times 0 in to your ArrayList
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