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How do I get the row count of a pandas DataFrame?
...s @Dan Allen noted in the comments len(df.index) and df[0].count() are not interchangeable as count excludes NaNs,
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Creating instance of type without default constructor in C# using reflection
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I originally posted this answer here, but here is a reprint since this isn't the exact same question but has the same answer:
FormatterServices.GetUninitializedObject() will create an instance without calling a constructor. I found this class by using Reflector and digging throu...
Why doesn't delete set the pointer to NULL?
I always wondered why automatic setting of the pointer to NULL after delete is not part of the standard. If this gets taken care of then many of the crashes due to an invalid pointer would not occur. But having said that I can think of couple of reasons why the standard would have restricted this:...
Android: ScrollView force to bottom
...lastChild = scrollLayout.getChildAt(scrollLayout.getChildCount() - 1);
int bottom = lastChild.getBottom() + scrollLayout.getPaddingBottom();
int sy = scrollLayout.getScrollY();
int sh = scrollLayout.getHeight();
int delta = bottom - (sy + sh);
scrollLayout.smoothScrollBy(0, delt...
How to choose the id generation strategy when using JPA and Hibernate
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The API Doc are very clear on this.
All generators implement the interface org.hibernate.id.IdentifierGenerator. This is a very simple interface. Some applications can choose to provide their own specialized implementations, however, Hibernate provides a range of built-in implementations. ...
Dialog with transparent background in Android
...r/transparent</item>
<item name="android:colorBackgroundCacheHint">@null</item>
</style>
One can set this theme to dialog as below
final Dialog dialog = new Dialog(this, R.style.DialogCustomTheme);
Enjoy!!
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Differences in auto-unboxing between Java 6 vs Java 7
...is explained in this email:
Bottom line: If the spec. allows (Object)(int) it must also be allowing (int)(Object).
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Delete duplicate records in SQL Server?
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and T1.uniqueField > T2.uniqueField
(this assumes that you have an integer based unique field)
Personally though I'd say you were better off trying to correct the fact that duplicate entries are being added to the database before it occurs rather than as a post fix-it operation.
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How to set tint for an image view programmatically in android?
Need to set tint for an image view... I am using it the following way:
22 Answers
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Map Tiling Algorithm
...to me. I'm dealing with a case where some tiles cannot transition directly into others. For example, the "dirt" tiles can transition into "light grass" and "light grass" can transition into "medium grass." Tiled (mapeditor.org) does a great job of handling this by implementing some type of tree sear...