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Passing arrays as parameters in bash
...y at all, but a list of its elements, which are re-assembled into an array by called_function(), but it worked for me. Somewhat later Ken posted his solution, but I kept mine here for "historic" reference.
calling_function()
{
variable="a"
array=( "x", "y", "z" )
called_function "${vari...
Check if event is triggered by a human
...ttached to an event and I would like it to execute only if it is triggered by a human, and not by a trigger() method. How do I tell the difference?
...
What is .sln.docstates file created by Visual Studio Productivity Power Tools?
....docstates file new in this
release of the Pro Power Tools. It is
used by the Document Tab Well
extension to persist and hydrate the
state of the floating tab wells. This
information was being stored in the
hidden .suo file but we
had to move it to a separate file to
fix a set of cra...
How can one display images side by side in a GitHub README.md?
...etween two photos in my README.md which is why I want to display them side-by-side. Here is how the two images are placed currently. I want to show the two Solarized color schemes side by side instead of top and bottom. Help would be much appreciated, thanks!
...
typedef fixed length array
...that it's an array type. If used as a function argument, it will be passed by reference, not by value, and the sizeof for it will then be wrong.
A better solution would be
typedef struct type24 { char x[3]; } type24;
You probably also want to be using unsigned char instead of char, since the lat...
Is char signed or unsigned by default?
In the book "Complete Reference of C" it is mentioned that char is by default unsigned.
7 Answers
...
Invalid default value for 'create_date' timestamp field
...d].
and set sql_mode to the following:
NO_ZERO_IN_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
Save and then restart mysql service by doing:
sudo service mysql restart
share
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...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
....table/wiki
library(data.table)
df2 <- setDT(df1)[, lapply(.SD, sum), by=.(year, month), .SDcols=c("x1","x2")]
setDF(df2) # convert back to dataframe
Using the plyr package
require(plyr)
df2 <- ddply(df1, c("year", "month"), function(x) colSums(x[c("x1", "x2")]))
Using summarize() from ...
Sourcemaps off by one line in Chrome, with Ruby on Rails, Webpack, and React JS
I'm having an issue where the sourcemaps generated by Webpack using the inline-source-map configuration setting are off by one line when I use the Chrome devtools debugger.
Webpack is set up inside a Ruby on Rails application to generate a concatenated, unminified JavaScript file composed of a cou...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...ROM boss
LEFT JOIN subordinate on subordinate.boss_id = boss.boss_id
GROUP BY boss.id
But don't use COUNT(*) for LEFT joins, as that will return 1 even if the subordinate table doesn't match anything from parent table
SELECT boss.boss_id, COUNT(*)
FROM boss
LEFT JOIN subordinate on subordinate.bo...