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Extracting numbers from vectors of strings
...
as.numeric(sub("\\D+","",years)). If there were letters before and |or after, then gsub
– Onyambu
Mar 5 '18 at 7:25
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...
How should one use std::optional?
...ng data:
void your_client_code(some_socket_object& socket)
{
char raw_data[1024]; // max 1024 bytes of raw data (for example)
while(socket.read(raw_data, 1024))
{
if(auto block = cache_and_get_block(raw_data))
{
// process *block here
// then ...
Bash: Syntax error: redirection unexpected
...lem from my Dockerfile as I had:
RUN bash < <(curl -s -S -L https://raw.githubusercontent.com/moovweb/gvm/master/binscripts/gvm-installer)
However, according to this issue, it was solved:
The exec form makes it possible to avoid shell string munging, and
to RUN commands using a base ...
onKeyPress Vs. onKeyUp and onKeyDown
...into an input element.
The user selects the text 12345.
The user types the letter A.
When the keypress event fires after entering the letter A, the text box now contains only the letter A.
But:
Field.val() is 12345.
$Field.val().length is 5
The user selection is an empty string (preventing you ...
How to save a git commit message from windows cmd?
...ss Esc several times if you are uncertain)
Type :q! enter
(that is, colon, letter q, exclamation mark, enter), this tells Vim to discard any changes and exit)
Git will then respond:
Aborting commit due to empty commit message
and you are once again free to commit using:
git commit –m "your...
Summarizing multiple columns with dplyr? [duplicate]
...character type
)
df %>% group_by(grp) %>%
summarise_each(.vars = letters[1:4],
.funs = c(mean="mean"))
# `summarise_each()` is deprecated.
# Use `summarise_all()`, `summarise_at()` or `summarise_if()` instead.
# To map `funs` over a selection of variables, use `summarise_a...
How do you do a case insensitive search using a pattern modifier using less?
...ase-insensitive with SmartCasing, i.e if your search contains an uppercase letter, then the search will be case-sensitive, otherwise, it will be case-insensitive. Think of it as :set smartcase in Vim.
E.g.: with -i, a search for 'log' in 'Log,..' will match, whereas 'Log' in 'log,..' will not matc...
Remove non-numeric characters (except periods and commas) from a string
...
If letters are always in the beginning or at the end, you can simply just use trim...no regex needed
$string = trim($string, "a..zA..Z"); // this also take care of lowercase
"AR3,373.31" --> "3,373.31"
"12.322,11T" --> "...
Naming convention for Scala constants?
...style (and I do mean officially) is the first style, camel case with first letter are upper case. It's laid down clearly by Odersky on Programming in Scala.
The style is also followed by the standard library, and has some support in language semantics: identifiers starting with upper case are treat...
Why is using onClick() in HTML a bad practice?
...write:
<button (click)="someAction()">Click Me</button>
In raw js/html the equivalent of this will be
<button onclick="someAction()">Click Me</button>
The difference is that in raw js onclick event is run in the global scope - but the frameworks provide encapsulation.
...