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How to write multiple line string using Bash with variables?
...command used (echo) is wrong.
Correct would be:
#!/bin/bash
kernel="2.6.39"
distro="xyz"
cat >/etc/myconfig.conf <<EOL
line 1, ${kernel}
line 2,
line 3, ${distro}
line 4 line
...
EOL
cat /etc/myconfig.conf
This construction is referred to as a Here Document and can be found in the B...
Easiest way to upgrade eclipse 3.7 to 4.2 (Juno)
So since Eclipse juno is based on 4.2 instead of 3.7, what is the easiest way to upgrade to it, short of installing a separate copy of juno and re-installing all my existing plugins from 3.7 into it?
...
Why does the order of the loops affect performance when iterating over a 2D array?
...mensional. So while you imagine your array like this:
0,0 | 0,1 | 0,2 | 0,3
----+-----+-----+----
1,0 | 1,1 | 1,2 | 1,3
----+-----+-----+----
2,0 | 2,1 | 2,2 | 2,3
Your computer stores it in memory as a single line:
0,0 | 0,1 | 0,2 | 0,3 | 1,0 | 1,1 | 1,2 | 1,3 | 2,0 | 2,1 | 2,2 | 2,3
In the 2...
Double vs. BigDecimal?
...
463
A BigDecimal is an exact way of representing numbers. A Double has a certain precision. Working ...
Homebrew install specific version of formula?
...a, it puts it in a versioned directory like /usr/local/Cellar/postgresql/9.3.1. Only symbolic links to this folder are then installed globally. In principle, this makes it pretty easy to switch between two installed versions. (*)
If you have been using homebrew for longer and never removed older ve...
Repeat each row of data.frame the number of times specified in a column
...), 1:2]
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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When to use ' (or quote) in Lisp?
... passed to it are evaluated. This means you can write this:
(* (+ a 2)
3)
Which in turn evaluates (+ a 2), by evaluating a and 2. The value of the symbol a is looked up in the current variable binding set, and then replaced. Say a is currently bound to the value 3:
(let ((a 3))
(* (+ a 2)
...
Difference between a Seq and a List in Scala
... |
edited Sep 6 '18 at 14:39
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answered Jun 2 '12 at 23:48
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Best way to find the intersection of multiple sets?
...tiple arguments to set.intersection(), like
u = set.intersection(s1, s2, s3)
If the sets are in a list, this translates to:
u = set.intersection(*setlist)
where *a_list is list expansion
Note that set.intersection is not a static method, but this uses the functional notation to apply intersec...