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Applying a function to every row of a table using dplyr?
...rows
How we add the output of the function is controlled by the .collate param. There's three options: list, rows, cols. When our output has length 1, it doesn't matter whether we use rows or cols.
iris %>%
by_row(.collate = "cols", ..f = function(this_row) {
this_row[1:4] %>% unlist...
Perform an action in every sub-directory using Bash
...
Also, note you need to tweak the find params if you want recursive or non-recursive behavior.
– Chris Tonkinson
Oct 23 '10 at 16:34
33
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AngularJS Directive Restrict A vs E
...n html elements will make html validation fail.
Directives with equal one parameter can done like this:
<div data-my-directive="ValueOfTheFirstParameter"></div>
Instead of this:
<my-directive my-param="ValueOfTheFirstParameter"></my-directive>
We dont use custom html el...
What's the difference between a mock & stub?
... passed around but never actually used. Usually they are just used to fill parameter lists.
Fake objects actually have working implementations, but usually take some shortcut which makes them not suitable for production (an in memory database is a good example).
Stubs provide canned answers to c...
Extract hostname name from string
...tename.com:1234/dir/file.txt"));
console.log(extractHostname("example.com?param=value"));
console.log(extractHostname("https://facebook.github.io/jest/"));
console.log(extractHostname("//youtube.com/watch?v=ClkQA2Lb_iE"));
console.log(extractHostname("http://localhost:4200/watch?v=ClkQA2Lb_iE"))...
Getting attributes of Enum's value
... attribute on an enum field value
/// </summary>
/// <typeparam name="T">The type of the attribute you want to retrieve</typeparam>
/// <param name="enumVal">The enum value</param>
/// <returns>The attribute of type T that exists on the enum value&...
Passing an array to a query using a WHERE clause
...($in);
SQL;
$statement = $mysqli->prepare($select);
$statement->bind_param(str_repeat('i', count($ids)), ...$ids);
$statement->execute();
$result = $statement->get_result();
Explanation:
Use the SQL IN() operator to check if a value exists in a given list.
In general it looks like this...
Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
... String.Concat in Reflector, you'll see it:
// while looping through the parameters
strArray[i] = (str == null) ? Empty : str;
// then concatenate that string array
(MSDN mentions it, too: http://msdn.microsoft.com/en-us/library/k9c94ey1.aspx)
On the other hand, ToString() is an instance meth...
Can a Byte[] Array be written to a file in C#?
.../ Convert the Binary AnyFile to Byte[] format
/// </summary>
/// <param name="image"></param>
/// <returns></returns>
public static byte[] ConvertANYFileToBytes(HttpPostedFileBase image)
{
byte[] imageBytes = null;
BinaryReader reader = new BinaryReader(image.In...
Is there a way to make a PowerShell script work by double clicking a .ps1 file?
...icted. Note the change at the end of the command which allows zero or more parameters to be passed to the PowerShell script. Quotation marks and spacing around the percent signs should be exactly as shown.
– Glenn Slayden
Nov 16 '16 at 22:39
...