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How to test if list element exists?
...es(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[["a"]] is safer than foo$a, since the latter uses partial matching and thus might also match a longer name:
x <- list(abc=4)
x$a # 4, since it partially matches abc
x[["a"]] # NULL, no match
[UPDATE] So, back t...
How to store a dataframe using Pandas
... it back using:
df = pd.read_pickle(file_name)
Note: before 0.11.1 save and load were the only way to do this (they are now deprecated in favor of to_pickle and read_pickle respectively).
Another popular choice is to use HDF5 (pytables) which offers very fast access times for large datasets:
...
What are the differences between git remote prune, git prune, git fetch --prune, etc
...ed under refs/remotes/...)
(e.g., local repo, refs/remotes/origin/master)
And a local branch that might be tracking the remote branch
(e.g., local repo, refs/heads/master)
Let's start with git prune. This removes objects that are no longer being referenced, it does not remove references. In yo...
How do I calculate percentiles with python/numpy?
...ed in the SciPy Stats package. It has the percentile function you're after and many other statistical goodies.
percentile() is available in numpy too.
import numpy as np
a = np.array([1,2,3,4,5])
p = np.percentile(a, 50) # return 50th percentile, e.g median.
print p
3.0
This ticket leads me to b...
Which .NET Dependency Injection frameworks are worth looking into? [closed]
Which C#/.NET Dependency Injection frameworks are worth looking into?
And what can you say about their complexity and speed.
...
How can I properly handle 404 in ASP.NET MVC?
.../shay/archive/2009/03/06/real-world-error-hadnling-in-asp-net-mvc-rc2.aspx and works in ASP.net MVC 1.0 as well
Here's how I handle http exceptions:
protected void Application_Error(object sender, EventArgs e)
{
Exception exception = Server.GetLastError();
// Log the exception.
ILogger ...
How to create a density plot in matplotlib?
...hat you generated with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the function covariance_factor of the gaussian_kde class. First, here is what you get without changing that function:
However, if I use the follo...
Crontab Day of the Week syntax
...
0 and 7 both stand for Sunday, you can use the one you want, so writing 0-6 or 1-7 has the same result.
Also, as suggested by @Henrik, it is possible to replace numbers by shortened name of days, such as MON, THU, etc:
0 - Su...
Convert integer into byte array (Java)
...order ensures that result[0] == 0xAA, result[1] == 0xBB, result[2] == 0xCC and result[3] == 0xDD.
Or alternatively, you could do it manually:
byte[] toBytes(int i)
{
byte[] result = new byte[4];
result[0] = (byte) (i >> 24);
result[1] = (byte) (i >> 16);
result[2] = (byte) (i ...
With MySQL, how can I generate a column containing the record index in a table?
...rt allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE league_girl (position int, username varchar(10), score int);
INSERT INTO league_girl VALUES (1, 'a', 10);
INSERT INTO league_girl VALUES (2, 'b', 25);
INSERT INTO league_girl VALUES (3, 'c', 75)...