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How to calculate the number of occurrence of a given character in each row of a column of strings?
...ng, fixed = "a")
# [1] 2 1 0
benchmark
Compared to the fastest approach from @42-'s answer and to the equivalent function from the stringr package for a vector with 30.000 elements.
library(microbenchmark)
benchmark <- microbenchmark(
stringi = stringi::stri_count(test.data$string, fixed =...
Can a C++ enum class have methods?
...ass isn't a class.
Usually the need to have methods for an enum results from the reason that it's not a regular (just incrementing) enum, but kind of bitwise definition of values to be masked or need other bit-arithmetic operations:
enum class Flags : unsigned char {
Flag1 = 0x01 , // Bit #0...
Python import csv to list
...
How to use your 1st solution but with only some columns from the csv file?
– Sigur
May 6 '17 at 3:13
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show 5 more commen...
include antiforgerytoken in ajax post ASP.NET MVC
...ighlight is all messed up. It ends up like this (removed the single-quotes from the returned result too, so that it behaves like any MVC helper, for instance @Url): '@Html.AntiForgeryTokenName' : '@Html.AntiForgeryTokenValue'
– Askolein
Mar 18 '14 at 9:05
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How can I generate an MD5 hash?
...
From Java 11 on, you can use hashtext = "0".repeat(32 - hashtext.length()) + hashtext instead of the while, so the editors won't give you a warning that you're doing string concatenation inside a loop.
–...
Shards and replicas in Elasticsearch
...age to understand it. If I download Elasticsearch and run the script, then from what I know I have started a cluster with a single node. Now this node (my PC) have 5 shards (?) and some replicas (?).
...
JavaScript blob filename without link
...er than a particular threshold. e.g-> 2 MB for chrome. This size varies from browser to browser.
– manojadams
Sep 2 '17 at 15:58
5
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How to use double or single brackets, parentheses, curly braces
...mp;1; date; } | tee logfile
# now we can calculate the duration of a build from the logfile
There is a subtle syntactic difference with ( ), though (see bash reference) ; essentially, a semicolon ; after the last command within braces is a must, and the braces {, } must be surrounded by spaces.
...
What is the use of “assert” in Python?
...ch easier to track down and fix bugs in your programs.
Here’s a summary from a tutorial on Python’s assertions I wrote:
Python’s assert statement is a debugging aid, not a mechanism for handling run-time errors. The goal of using assertions is to let developers find the likely root cause ...
How do you commit code as a different user?
...
Check out the --author option for git commit:
From the man page:
--author=<author>
Override the commit author. Specify an explicit author
using the standard A U Thor <author@example.com> format. Otherwise
<author> is assumed to be a pattern...