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Declaring variables inside or outside of a loop
...lity.
Performance doesn't matter for today's compilers.(in this scenario)
From a maintenance perspective, 2nd option is better.
Declare and initialize variables in the same place, in the narrowest scope possible.
As Donald Ervin Knuth told:
"We should forget about small efficiencies, say about...
Converting bytes to megabytes
I've seen three ways of doing conversion from bytes to megabytes:
9 Answers
9
...
How do I list the functions defined in my shell?
... supply filenames/line#s even when extdebug is enabled, which is not clear from the documentation, nor is it particularly intuitive, IMO.
– Ron Burk
May 16 '17 at 8:35
...
What are the differences between vector and list data types in R?
... of a specific type.
Another use is when representing a model: the result from lm returns a list that contains a bunch of useful objects.
d <- data.frame(a=11:13, b=21:23)
is.list(d) # TRUE
str(d)
m <- lm(a ~ b, data=d)
is.list(m) # TRUE
str(m)
Atomic vectors (non-list like, but numeric, ...
Removing a model in rails (reverse of “rails g model Title…”)
...
Ye thanks. I restored the migration from the Trash but it turns out I had another missing migration too so I'm going to do what you suggest
– Mike T
Jul 23 '13 at 7:03
...
Convert floating point number to a certain precision, and then copy to string
...r more information on option two, I suggest this link on string formatting from the Python documentation.
And for more information on option one, this link will suffice and has info on the various flags.
Python 3.6 (officially released in December of 2016), added the f string literal, see more inf...
When should I use the assets as opposed to raw resources in Android?
... that will act as a reference to
a file, meaning it can be easily accessed from other Android classes
and methods and even in Android XML files. Using the automatically
generated ID is the fastest way to have access to a file in Android.
The assets folder is an “appendix” directory. The R class...
How to find out the number of CPUs using python
...except (KeyError, ValueError):
pass
# jython
try:
from java.lang import Runtime
runtime = Runtime.getRuntime()
res = runtime.availableProcessors()
if res > 0:
return res
except ImportError:
pass
# BSD
try:
s...
Converting PKCS#12 certificate into PEM using OpenSSL
I have OpenSSL x64 on Windows 7 which I downloaded from openssl-for-windows on Google Code . I'm attempting to run:
5 Answ...
PowerShell: Setting an environment variable for a single command only
...v:FOO='BAR'; .\myscript; Remove-Item Env:\FOO
Just summarized information from other answers (thank you folks) which don't contain pure one-liners for some reason.
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