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Selecting with complex criteria from pandas.DataFrame
...5 9 30 900
6 2 80 700
7 2 80 400
8 5 80 300
9 7 70 800
We can apply column operations and get boolean Series objects:
>>> df["B"] > 50
0 False
1 True
2 True
3 True
4 False
5 False
6 True
7 True
8 True
9 True
Name: B
>>> (df[...
Changing the size of a column referenced by a schema-bound view in SQL Server
...e or tables. When
SCHEMABINDING is specified, the base
table or tables cannot be modified in
a way that would affect the view
definition. The view definition itself
must first be modified or dropped to
remove dependencies on the table that
is to be modified.
...
How to access accelerometer/gyroscope data from Javascript?
...leOrientation, true);
After registering your event listener (in this case, a JavaScript
function called handleOrientation()), your listener function
periodically gets called with updated orientation data.
The orientation event contains four values:
DeviceOrientationEvent.absol...
How to add an extra source directory for maven to compile and include in the build jar?
...
You can use the Build Helper Plugin, e.g:
<project>
...
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugi...
What does the caret operator (^) in Python do?
I ran across the caret operator in python today and trying it out, I got the following output:
5 Answers
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Android preferences onclick event
...
Badr,
You need to set android:key for the item, Then in your code you can do...
Assuming you use the following in your XML:
<Preference android:title="About" android:key="myKey"></Preference>
Then you can do the following in your code:
Preference myPref = (Preference) findPrefe...
Why does ~True result in -2?
...
@ofcapl Just wanted to say: Although int('1') is also 1 but ~'1' be a typeerror exception whereas ~True is not this is because bool is a subclass of int @ Martijn added this information in his answer.
– Gri...
Format a date using the new date time API
...
LocalDate represents just a date, not a DateTime. So "HH:mm:ss" make no sense when formatting a LocalDate. Use a LocalDateTime instead, assuming you want to represent both a date and time.
...
Can I set a breakpoint on 'memory access' in GDB?
I am running an application through gdb and I want to set a breakpoint for any time a specific variable is accessed / changed. Is there a good method for doing this? I would also be interested in other ways to monitor a variable in C/C++ to see if/when it changes.
...
What difference is there between WebClient and HTTPWebRequest classes in .NET?
...sing statements from both examples for brevity. You should definitely take care to dispose your web request objects properly.
In general, WebClient is good for quick and dirty simple requests and HttpWebRequest is good for when you need more control over the entire request.
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