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How to delete multiple values from a vector?
...vector like: a = c(1:10) and I need to remove multiple values, like: 2, 3, 5
8 Answers
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How to update Python?
...will stop receiving official updates from python.org in 2020. Also, Python-3.7 has been released. Check out Python-Future on how to make your Python-2 code compatible with Python-3. For updating conda, the documentation now recommends using conda update --all in each of your conda environments to up...
The $.param( ) inverse function in JavaScript / jQuery
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answered Jun 9 '11 at 19:23
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
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13 Answers
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Find integer index of rows with NaN in pandas dataframe
...n use to index back into df, e.g.:
df['a'].ix[index[0]]
>>> 1.452354
For the integer index:
df_index = df.index.values.tolist()
[df_index.index(i) for i in index]
>>> [3, 6]
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What's the difference between RANK() and DENSE_RANK() functions in oracle?
... assigned the same rank, with the next ranking(s) skipped. So, if you have 3 items at rank 2, the next rank listed would be ranked 5.
DENSE_RANK again gives you the ranking within your ordered partition, but the ranks are consecutive. No ranks are skipped if there are ranks with multiple items.
As...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
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Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 1...
What is an alternative to execfile in Python 3?
It seems they canceled in Python 3 all the easy way to quickly load a script by removing execfile()
12 Answers
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How to check if a float value is a whole number
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13 Answers
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Flatten an Array of Arrays in Swift
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Swift >= 3.0
reduce:
let numbers = [[1,2,3],[4],[5,6,7,8,9]]
let reduced = numbers.reduce([], +)
flatMap:
let numbers = [[1,2,3],[4],[5,6,7,8,9]]
let flattened = numbers.flatMap { $0 }
joined:
let numbers = [[1,2,3],[4],[5,6,7...