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How to convert a data frame column to numeric type?
... convert to numeric. I suggest that you should apply transform function in order to complete your task.
Now I'm about to demonstrate certain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
fac ...
What does (function($) {})(jQuery); mean?
...
Type 3, in order to work would have to look like this:
(function($){
//Attach this new method to jQuery
$.fn.extend({
//This is where you write your plugin's name
'pluginname': function(_options) {
...
Can you control how an SVG's stroke-width is drawn?
...
You can use CSS to style the order of stroke and fills. That is, stroke first and then fill second, and get the desired effect.
MDN on paint-order: https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/paint-order
CSS code:
paint-order: stroke;
...
must appear in the GROUP BY clause or be used in an aggregate function
...ax:
SELECT DISTINCT ON (cname)
cname, wmname, avg
FROM
makerar
ORDER BY
cname, avg DESC ;
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How can I make an entire HTML form “readonly”?
...ion to just list the 'selected' items, without checkboxes. Like on a pizza order confirmation: just list all the ingredients you selected.
– marc82ch
Feb 20 '15 at 12:53
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Efficient paging in SQLite with millions of records
...
Please note that you always have to use an ORDER BY clause; otherwise, the order is arbitrary.
To do efficient paging, save the first/last displayed values of the ordered field(s), and continue just after them when displaying the next page:
SELECT *
FROM MyTable
WHE...
My Understanding of HTTP Polling, Long Polling, HTTP Streaming and WebSockets
..., long poll, streaming.
Bi-direcitonal: WebSockets, plugin networking
In order of increasing latency (approximate):
WebSockets
Plugin networking
HTTP streaming
HTTP long-poll
HTTP polling
CORS (cross-origin support):
WebSockets: yes
Plugin networking: Flash via policy request (not sure about...
403 Forbidden vs 401 Unauthorized HTTP responses
... (or 3xx: redirection)
Checks are usually done in this order:
404 if resource is public and does not exist or 3xx redirection
OTHERWISE:
401 if not logged-in or session expired
403 if user does not have permission to access resource (file, json, ...)
404 if resource does not ex...
Grunt watch error - Waiting…Fatal error: watch ENOSPC
...the below command.
echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p
For Arch Linux add this line to /etc/sysctl.d/99-sysctl.conf:
fs.inotify.max_user_watches=524288
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Git cherry pick vs rebase
...nto it.
Tries to apply each of the saved commits (as if with git apply) in order. In our toy example it's just one commit, C3. Let's say its application will produce a commit C3'.
If all went well, the "experiment" reference is updated to point to the commit resulted from applying the last saved com...