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A numeric string as array key in PHP
... the value with a string key doesn't work, though. Add this line to your example: echo $data['12'];. It will give the error, "Notice: Undefined offset: 12 in - on line 5".
– L S
May 29 '16 at 9:47
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Dynamically select data frame columns using $ and a character value
...different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , ne...
Converting String to Int with Swift
...se a formula to calculate acceleration. However, since the values in the text boxes are string, I am unable to convert them to integers.
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Python multiprocessing PicklingError: Can't pickle
I am sorry that I can't reproduce the error with a simpler example, and my code is too complicated to post. If I run the program in IPython shell instead of the regular Python, things work out well.
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Are Javascript arrays sparse?
That is, if I use the current time as an index into the array:
7 Answers
7
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What is the best way to test for an empty string in Go?
...r enough. It is more a matter of personal taste and about clarity.
Russ Cox writes in a golang-nuts thread:
The one that makes the code clear.
If I'm about to look at element x I typically write
len(s) > x, even for x == 0, but if I care about
"is it this specific string" I tend to wri...
Why do people still use primitive types in Java?
Since Java 5, we've had boxing/unboxing of primitive types so that int is wrapped to be java.lang.Integer , and so and and so forth.
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How to use ADB to send touch events to device using sendevent command?
...simulate miscellaneous input events. To simulate tapping, it's:
input tap x y
You can use the adb shell ( > 2.3.5) to run the command remotely:
adb shell input tap x y
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Clean ways to write multiple 'for' loops
...ns, we usually need to write a for loop for each of its dimensions. For example:
16 Answers
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How do I clone a generic list in C#?
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You can use an extension method.
static class Extensions
{
public static IList<T> Clone<T>(this IList<T> listToClone) where T: ICloneable
{
return listToClone.Select(item => (T)item.Clone()).ToList();
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