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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...
How to write a simple database engine [closed]
...ny, so I am hoping someone else can point me in the right direction. Basically, I would like information on the following:
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Accessing Session Using ASP.NET Web API
...ed bonus that we can fetch the base URL in javascript for making the AJAX calls:
_Layout.cshtml
<body>
@RenderBody()
<script type="text/javascript">
var apiBaseUrl = '@Url.Content(ProjectNameSpace.WebApiConfig.UrlPrefixRelative)';
</script>
@RenderSectio...
Git pull after forced update
... the working tree since <commit> are discarded.
If you want to actually keep whatever changes you've got locally - do a --soft reset instead. Which will update the commit history for the branch, but not change any files in the working directory (and you can then commit them).
Rebase
You ca...
How to fix corrupted git repository?
... have a corrupted local repo, but a trusted remote.
# This script replaces all your history with that of the remote.
# If there is a .git, it is backed up as .git_old, removing the last backup.
# This does not affect your working tree.
#
# This does not currently work with submodules!
# This will ab...
Embedded MongoDB when running integration tests
...ed mongo for each test fails most of the tests. Its better to start before all the tests and shutdown once all have executed
– DBS
Apr 30 '19 at 5:36
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Looping over arrays, printing both index and value
...., not splitting them on whitespace. If foo=(x 'y z'), then f "${foo[@]}" calls f with two arguments, x and 'y z'. Metadata queries like "${!foo[@]}" and "${#foo[@]}" similarly act on foo as an array.
– BallpointBen
Sep 5 '18 at 1:23
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Replace non-ASCII characters with a single space
I need to replace all non-ASCII (\x00-\x7F) characters with a space. I'm surprised that this is not dead-easy in Python, unless I'm missing something. The following function simply removes all non-ASCII characters:
...
Is there a difference between foreach and map?
...important point to mention (this is particularly true in Scala) is that a call to map does not result in the execution of its underlying logic until when the expected transformed list is summoned. In contrast, foreach's operation is computed immediately.
– solimant
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How to apply bindValue method in LIMIT clause?
...
@Ross I cannot specifically answer this- but I can point out that LIMIT and OFFSET are features that were glued on AFTER all this PHP/MYSQL/PDO madness hit the dev circuit... In fact, I believe it was Lerdorf himself who oversaw LIMIT implementatio...