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Relative frequencies / proportions with dplyr
...
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vigne...
How to uninstall Python 2.7 on a Mac OS X 10.6.4?
... PATH variable by reverting my .bash_profile . But I also want to remove all directories, files, symlinks, and entries that got installed by the Python 2.7 install package. I've got the install package from http://www.python.org/ . What directories/files/configuration file entries do I need to re...
What's the difference between Task.Start/Wait and Async/Await?
...ot. How would you like it if waiting for a Task that takes 10 ms would actually execute a 10 hour-long Task on your thread, thus blocking you for the whole 10 hours?
– svick
Apr 20 '13 at 11:10
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Glorified classes in the Java language
... lot of different answers, so I thought it would be useful to collect them all (and add some):
Classes
AutoBoxing classes - the compiler only allows for specific classes
Class - has its own literals (int.class for instance). I would also add its generic typing without creating new instances.
Stri...
How to customize a Spinner in Android
...er"
android:src="@mipmap/drop" />
</RelativeLayout>
Finally looks like below image and it is everywhere clickable in round area and no need to write click Lister for imageView.
Step3: For drop-down design, remove the line from Dropdown ListView and change the background color,...
How do I inspect the view hierarchy in iOS?
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I've got: error: cannot find interface declaration for '$__lldb_objc_class' any ideas? (lldb) po [[UIWindow keyWindow] recursiveDescription] error: cannot find interface declaration for '$__lldb_objc_class' error: cannot find interface declaration for '$__lldb_objc_class' error:...
Are there any suggestions for developing a C# coding standards / best practices document? [closed]
...recent AI graduate (circa 2 years) working for a modest operation. It has fallen to me (primarily as I'm the first 'adopter' in the department) to create a basic (read useful?) C# coding standards document.
...
CListCtrl 扩展风格设置方法：SetExtendedStyle和ModifyStyleEx 区别 - C++...
...常常想到用ModifyStyleEx 来设定，代码如下：ModifyStyleEx(0,LVS_EX_GRIDLINES)
这是不正确的，正确的设定应该是：SetExtendedStyle(LVS_EX_GRIDLINES)
那么，ModifyStyleEx和SetExtendedStyle区别在哪里？实际上，ModifyStyleEx只是对窗...
UISegmentedControl below UINavigationbar in iOS 7
...WillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self _moveHairline:YES];
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
[self _moveHairline:NO];
}
- (void)_moveHairline:(BOOL)appearing
{
// move the hairline below the segmentbar
...
When and why JPA entities should implement Serializable interface?
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This usually happens if you mix HQL and native SQL queries. In HQL, Hibernate maps the types you pass in to whatever the DB understands. When you run native SQL, then you must do the mapping yourself. If you don't, then the default m...