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Selecting a row of pandas series/dataframe by integer index
...
echoing @HYRY, see the new docs in 0.11
http://pandas.pydata.org/pandas-docs/stable/indexing.html
Here we have new operators, .iloc to explicity support only integer indexing, and .loc to explicity support only label indexing
e.g. imagine this scenario
In ...
Scaling Node.js
...like to know what the general principles are for scaling node up to, say, 20 queries per second.
1 Answer
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How to calculate cumulative normal distribution?
...le:
>>> from scipy.stats import norm
>>> norm.cdf(1.96)
0.9750021048517795
>>> norm.cdf(-1.96)
0.024997895148220435
In other words, approximately 95% of the standard normal interval lies within two standard deviations, centered on a standard mean of zero.
If you need t...
Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data fr...
Can someone explain this 'double negative' trick? [duplicate]
...ue.
The "falsey" values are:
false
NaN
undefined
null
"" (empty string)
0
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How to sort a list in Scala by two fields?
...g.String) ).
– senia
Jun 18 '14 at 10:16
5
@SachinK: You could implement customOrdering as Orderi...
how to mysqldump remote db from local machine
...
250
As I haven't seen it at serverfault yet, and the answer is quite simple:
Change:
ssh -f -L3310...
Default value to a parameter while passing by reference in C++
...
104
You can do it for a const reference, but not for a non-const one. This is because C++ does not ...
How would I extract a single file (or changes to a file) from a git stash?
...D when the
stash was created.
So you can treat stash (e.g. stash@{0} is first / topmost stash) as a merge commit, and use:
$ git diff stash@{0}^1 stash@{0} -- <filename>
Explanation: stash@{0}^1 means the first parent of the given stash, which as stated in the explanation above is ...
How to position a DIV in a specific coordinates?
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answered Jul 23 '11 at 20:01
Michael BerkowskiMichael Berkowski
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