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Stream vs Views vs Iterators
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First, they are all non-strict. That has a particular mathematical meaning related to functions, but, basically, means they are computed on-demand instead of in advance.
Stream is a lazy list indeed. In fact, in Scala, a Stream is a List wh...
Specifying colClasses in the read.csv
... the read.csv function in R. In my data, the first column "time" is basically a character vector while the rest of the columns are numeric.
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What is the difference between “#!/usr/bin/env bash” and “#!/usr/bin/bash”?
...en Ubuntu 16.04 if not later).
Another downside is that since you aren't calling an explicit executable, it's got the potential for mistakes, and on multiuser systems security problems (if someone managed to get their executable called bash in your path, for example).
#!/usr/bin/env bash #lends yo...
Should __init__() call the parent class's __init__()?
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In Python, calling the super-class' __init__ is optional. If you call it, it is then also optional whether to use the super identifier, or whether to explicitly name the super class:
object.__init__(self)
In case of object, calling th...
Center image in div horizontally [duplicate]
.../* for the img inside your div */
display: block;
margin: 0 auto;
That's all.
Note, that you'll also have to set an initial min-width for your outer div.
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Reference: Comparing PHP's print and echo
...hat while they appear to users as two distinct constructs, they are both really shades of echo if you get down to basics, i.e. look at the internal source code. That source code involves the parser as well as opcode handlers. Consider a simple action such as displaying the number zero. Whether you ...
Why `null >= 0 && null
... number and assigns 0 to the variable if not, where the variable is initially null or undefined .
5 Answers
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How do I avoid capturing self in blocks when implementing an API?
...ied inside the block (we're not doing that) but also they are not automatically retained when the block is retained (unless you are using ARC). If you do this, you must be sure that nothing else is going to try to execute the block after the MyDataProcessor instance is released. (Given the structure...
Checkout remote branch using git svn
... svn show-ignore >> .git/info/exclude
You should now be able to see all the Subversion branches on the git side:
git branch -r
Say the name of the branch in Subversion is waldo. On the git side, you'd run
git checkout -b waldo-svn remotes/waldo
The -svn suffix is to avoid warnings of the ...
Replace one character with another in Bash
.... Example:
foo=" "
# replace first blank only
bar=${foo/ /.}
# replace all blanks
bar=${foo// /.}
See http://tldp.org/LDP/abs/html/string-manipulation.html for more details.
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