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Why can't I assign a *Struct to an *Interface?
... var pi *Interface
pi = new(Interface)
*pi = ps
_, _ = pi, ps
}
Compiles OK. See also here.
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List comprehension: Returning two (or more) items for each item
...bda x: x + 2
>>> g = lambda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_itera...
Using CookieContainer with WebClient class
... limited functionalty. Before I knew about this option, I wrote lots of really painful code at the HttpWebRequest layer because WebClient almost, but not quite, did what I needed. Derivation is much easier.
Another option is to use the regular WebClient class, but manually populate the Cookie he...
How to make Entity Framework Data Context Readonly
...nsumer.
public class ReadOnlyDataContext
{
private readonly DbContext _dbContext;
public ReadOnlyDataContext(DbContext dbContext)
{
_dbContext = dbContext;
}
public IQueryable<TEntity> Set<TEntity>() where TEntity : class
{
return _dbContext.Set...
ImportError: numpy.core.multiarray failed to import
... following command in my Mac terminal:
python -c "import numpy;print(numpy.__version__);print(numpy.__file__)";
This command gave me the version and location of numpy that I was using (turned out it was 1.6.2). I went to this location and manually replaced it with the numpy folder for 1.8, which re...
Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
mysql :: insert into table, data from another table?
...
INSERT INTO action_2_members (campaign_id, mobile, vote, vote_date)
SELECT campaign_id, from_number, received_msg, date_received
FROM `received_txts`
WHERE `campaign_id` = '8'
...
Git push/clone to new server
...s something I can't work out. After creating and using a git repository locally on my Mac, can I push a copy to another server somewhere else? I am behind a firewall so unfortunately I can't run git clone from the other machine.
...
How to get default gateway in Mac OSX
...sult thus looks like this:
192.168.195.1
In this case, netstat displays all result, grep only selects the line with 'default' in it, and awk further matches the pattern to display the second column in the text.
You can similarly use route -n get default command to get the required result. The fu...
Setting environment variables for accessing in PHP when using Apache
I have a Linux environment and I have a PHP Web Application that conditionally runs based on environment variables using getenv in PHP. I need to know how these environment variables need to be set for the application to work correctly. I am not sure how to set this up on Apache.
...