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_=> what does this underscore mean in Lambda expressions?
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ChaosPandionChaosPandion
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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
An example of how to use getopts in bash
I want to call myscript file in this way:
7 Answers
7
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How can I expand the full path of the current file to pass to a command in Vim?
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162
:!mycommand %:p
Related:
:!cd %:p:h
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Is there a max array length limit in C++?
...se memory is full. For example, a vector<int> of a given size n typically takes multiple times as much memory as an array of type vector<char> (minus a small constant value), since int is usually bigger than char. Therefore, a vector<char> may contain more items than a vector<in...
Is it possible to implement dynamic getters/setters in JavaScript?
...Here's a simple example that turns any property values that are strings to all caps on retrieval:
"use strict";
if (typeof Proxy == "undefined") {
throw new Error("This browser doesn't support Proxy");
}
let original = {
"foo": "bar"
};
let proxy = new Proxy(original, {
get(...
Count Rows in Doctrine QueryBuilder
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He accepted your answer so I guess all is well. I was under the impression that he only wanted a count without the overhead of actually retrieving the rows which my example shows. There is of course no reason why where conditions could not be added.
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ActiveModel::ForbiddenAttributesError when creating new user
...mit(:what, :ever)
end
Update:
Here's a continuation project for CanCan called CanCanCan, which looks promising:
CanCanCan
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Where is the WPF Numeric UpDown control?
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answered Feb 18 '13 at 16:01
StackedStacked
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PHP code to convert a MySQL query to CSV [closed]
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SELECT * INTO OUTFILE "c:/mydata.csv"
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $sel...