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How to make good reproducible pandas examples
Having spent a decent amount of time watching both the r and pandas tags on SO, the impression that I get is that pandas questions are less likely to contain reproducible data. This is something that the R community has been pretty good about encouraging, and thanks to guides like this , newc...
Remove an entire column from a data.frame in R
...S
6 chr1 exon
As pointed out in the comments, here are some other possibilities:
Data[2] <- NULL # Wojciech Sobala
Data[[2]] <- NULL # same as above
Data <- Data[,-2] # Ian Fellows
Data <- Data[-2] # same as above
You can remove multiple columns via:
Data[1:2] <- list(N...
How to use the TextWatcher class in Android?
Can anyone tell me how to mask the substring in EditText or how to change EditText substring input to password type or replace by another character like this 123xxxxxxxxx3455
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How to document class attributes in Python? [closed]
I'm writing a lightweight class whose attributes are intended to be publicly accessible, and only sometimes overridden in specific instantiations. There's no provision in the Python language for creating docstrings for class attributes, or any sort of attributes, for that matter. What is the expec...
JavaScript - cannot set property of undefined
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you never set d[a] to any value.
Because of this, d[a] evaluates to undefined, and you can't set properties on undefined.
If you add d[a] = {} right after d = {} things should work as expected.
Alternatively, you could use an object initializer:
d[a] = {
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Is Ruby pass by reference or by value?
@user object adds errors to the lang_errors variable in the update_lanugages method.
when I perform a save on the @user object I lose the errors that were initially stored in the lang_errors variable.
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Entity Framework - Invalid Column Name '*_ID"
I've narrowed this down to some issue between Code First and Database first EF, but I'm not sure how to fix it. I'll try to be as clear as I can, but I honestly am missing some of the understanding here myself. This is Entity Framework 4.4
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How to get line count of a large file cheaply in Python?
...(hundreds of thousands of lines) in python. What is the most efficient way both memory- and time-wise?
40 Answers
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+ operator for array in PHP?
...e right-hand array appended to the left-hand array; for keys that exist in both arrays, the elements from the left-hand array will be used, and the matching elements from the right-hand array will be ignored.
So if you do
$array1 = ['one', 'two', 'foo' => 'bar'];
$array2 = ['three'...
Strings are objects in Java, so why don't we use 'new' to create them?
We normally create objects using the new keyword, like:
15 Answers
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