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Java String array: is there a size of method?
I come from a php background and in php, there is an array_size() function which tells you how many elements in the array are used.
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Locate current file in IntelliJ
...ructure, file structure etc).
(Note you can also set AutoScroll to Source and AutoScroll from source using the two "boxes with arrows" buttons above the project structure view but this can get annoying when it shoves you into the JDK source because you followed a reference to java.io.File.
The key...
Setting table column width
...group>
<!-- Put <thead>, <tbody>, and <tr>'s here! -->
<tbody>
<tr>
<td style="background-color: #777">15%</td>
<td style="background-color: #aaa">70%</td>
<t...
Default value of a type at Runtime [duplicate]
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There's really only two possibilities: null for reference types and new myType() for value types (which corresponds to 0 for int, float, etc) So you really only need to account for two cases:
object GetDefaultValue(Type t)
{
if (t.IsValueType)
return Activator.CreateInstance(...
Can you make valid Makefiles without tab characters?
...that Makefiles have a tab character preceding the the content of each command line, or it throws a syntax error.
10 Answe...
Efficiently checking if arbitrary object is NaN in Python / numpy / pandas?
...lues. As I iterate over the data set, I need to detect such missing values and handle them in special ways.
2 Answers
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Rails: select unique values from a column
...ing)
Result of this is a collection of Model objects. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (most efficient)
Model.uniq.pluck(:rating)
# rails 5+
Model.distinct.pluck(:rating)
U...
How to get the index of an item in a list in a single step?
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EDIT: If you're only using a List<> and you only need the index, then List.FindIndex is indeed the best approach. I'll leave this answer here for those who need anything different (e.g. on top of any IEnumerable<>).
Use the overload of Select which takes...
How to reverse a 'rails generate'
I want to delete all the files it created and roll back any changes made, but not necessarily to the database, but more to the config files.
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“unmappable character for encoding” warning in Java
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Absolutely. (This is better handled in C#, where unicode escaping is only applied in certain contexts - but then there's the dangerous \x escape sequence as well, which is awful.)
– Jon Skeet
Jan 21 '09 at 11:38
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