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Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
.Net picking wrong referenced assembly version
...r assembly you are using is referencing the old dll. Are you familiar with all of the other project references being used and do any of them have a reference to the Telerik dlls?
Can you put in a binding redirect in your web.config file like this?
<dependentAssembly>
<assemblyIdentity na...
If strings are immutable in .NET, then why does Substring take O(n) time?
...t tiny substrings from tiny strings, so how the complexity grows asymptotically is completely irrelevant.
The long answer is:
An immutable data structure built such that operations on an instance permit re-use of the memory of the original with only a small amount (typically O(1) or O(lg n)) of co...
Create new tmux session from inside a tmux session
... Thanks for the very complete answer, this answered a few of my questions all at once!
– mdekkers
Jun 1 '18 at 4:33
add a comment
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...
Pass a data.frame column name to a function
...l_name,col1,col2){
df$col_name <- df$col1 + df$col2
df
}
#Call foo() like this:
foo(dat,z,x,y)
The problem here is that df$col1 doesn't evaluate the expression col1. It simply looks for a column in df literally called col1. This behavior is described in ?Extract under the secti...
Record file copy operation with Git
...n (-C implies -M), and you can request more expensive copy detection among all files with --find-copies-harder or -C -C (which implies -C, which implies -M). See the git-diff manpage.
You can also configure git to always do rename detection by setting diff.renames to a boolean true value (e.g. true...
seek() function?
...
Regarding seek() there's not too much to worry about.
First of all, it is useful when operating over an open file.
It's important to note that its syntax is as follows:
fp.seek(offset, from_what)
where fp is the file pointer you're working with; offset means how many positions you wi...
Nodejs - Redirect url
...'/login') merely sends the login.html content in the response of the ajax call made. How do I rather open the page?
– Tarun
Oct 24 '16 at 20:03
...
Python: TypeError: cannot concatenate 'str' and 'int' objects [duplicate]
...ed by the last print statement.
You can assign the result of the str(c) call to c as correctly shown by @jamylak and then concatenate all of the strings, or you can replace the last print simply with this:
print "a + b as integers: ", c # note the comma here
in which case
str(c)
isn't nece...
contenteditable, set caret at the end of the text (cross-browser)
...
The following function will do it in all major browsers:
function placeCaretAtEnd(el) {
el.focus();
if (typeof window.getSelection != "undefined"
&& typeof document.createRange != "undefined") {
var range = document.c...