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cartesian product in pandas
...rom pandas import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6...
How to set versionName in APK filename using gradle?
...
229
I only have to change the version name in one place. The code is simple too.
The examples belo...
Get full path without filename from path that includes filename
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244
Path.GetDirectoryName()... but you need to know that the path you are passing to it does conta...
Why isn't String.Empty a constant?
...ated by Microsoft here in the Shared Source Common Language Infrastructure 2.0 Release. The file to look at is sscli20\clr\src\bcl\system\string.cs.
The Empty constant holds the empty
string value. We need to call the
String constructor so that the
compiler doesn't mark this as a
literal...
Guava: Why is there no Lists.filter() function?
...
dimo414
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answered Dec 10 '11 at 22:16
Dimitris AndreouDimitris Andreou...
How to create an object property from a variable value in JavaScript? [duplicate]
...a new property to 'myObj', name it 'string1' and give it a value of 'string2', but when I do it it returns 'undefined:
9 An...
Which version of C# am I using
...ndows\Microsoft.NET\Framework\v4.0.30319>csc /?
Microsoft (R) Visual C# 2010 Compiler version 4.0.30319.1
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Difference between objectForKey and valueForKey?
...an do the following:
NSNumber *anAccountNumber = [NSNumber numberWithInt:12345];
Account *newAccount = [[Account alloc] init];
[newAccount setAccountNumber:anAccountNUmber];
NSNumber *anotherAccountNumber = [newAccount accountNumber];
Using KVC, I can access the property dynamically:
NSNumber ...
Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
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126
Short of closing and reopening your tty (i.e. logging off and back on, which may also terminate...
I don't understand -Wl,-rpath -Wl,
...
286
The -Wl,xxx option for gcc passes a comma-separated list of tokens as a space-separated list o...