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How do I combine two data frames?
...
1st dataFrame
train.shape
result:-
(31962, 3)
2nd dataFrame
test.shape
result:-
(17197, 2)
Combine
new_data=train.append(test,ignore_index=True)
Check
new_data.shape
result:-
(49159, 3)
share
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Difference between repository and service?
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If you grok unit testing it might be clearer to think of repositories as the minimal abstraction to minimize the mocking needed to avoid database.
– Henry Heikkinen
Apr 7 '15 at 12:12
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Why do you have to call .items() when iterating over a dictionary in Python?
...he full tuple would be more intuitive for looping, but perhaps less so for testing for membership using in.
if key in counts:
counts[key] += 1
else:
counts[key] = 1
That code wouldn't really work if you had to specify both key and value for in. I am having a hard time imagining use case w...
How to find all the subclasses of a class given its name?
...sses__())
# [<class '__main__.Bar'>, <class '__main__.Baz'>]
Confirmation that the subclasses do indeed list Foo as their base:
for cls in Foo.__subclasses__():
print(cls.__base__)
# <class '__main__.Foo'>
# <class '__main__.Foo'>
Note if you want subsubclasses, you'...
How do I reflect over the members of dynamic object?
...meta object with an implementation of GetDynamicMemberNames without custom testing beyond is IDynamicMetaObjectProvider.
After getting the member names it's a little more work to get the value the right way, but Impromptu does this but it's harder to point to just the interesting bits and have it m...
How to send only one UDP packet with netcat?
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OS X works this: "echo -n "test" | nc -4u -w0 localhost 9999" as SimonW says
– Simon Unsworth
Aug 28 '17 at 17:12
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Possible heap pollution via varargs parameter
...led with List[] non-varargs type.
Here is an example:
public static void testCode(){
List[] b = new List[1];
test(b);
}
@SafeVarargs
public static void test(List<A>... a){
}
As you can see List[] b can contain any type of consumer, and yet this code compiles. If you use varargs, t...
Setting a system environment variable from a Windows batch file?
... where and then the name of the program (so in this case where setx.exe in testing this on a Server 2008 and Server 2008SP2 box I found that in both cases it existed at %windir%\System32\setx.exe
– aolszowka
Sep 20 '13 at 16:34
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Python: Get the first character of the first string in a list?
...tring.
If you have the following structure:
mylist = ['base', 'sample', 'test']
And want to get fist char for the first one string(item):
myList[0][0]
>>> b
If all first chars:
[x[0] for x in myList]
>>> ['b', 's', 't']
If you have a text:
text = 'base sample test'
t...
How do you merge two Git repositories?
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I can confirm that after this, git log rails/somefile will not display that file's commits history except the merge commit. As @artfulrobot suggested, check Greg Hewgill's answer. And you might need to use git filter-branch on the ...