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Which is more efficient, a for-each loop, or an iterator?
... there is no difference between using an iterator or the new for loop syntax, as the new syntax just uses the iterator underwater.
If however, you mean by loop the old "c-style" loop:
for(int i=0; i<list.size(); i++) {
Object o = list.get(i);
}
Then the new for loop, or iterator, can be a ...
postgresql - sql - count of `true` values
...select count(*) filter (where myCol)
from tbl;
The above query is a bad example in that a simple WHERE clause would suffice, and is for demonstrating the syntax only. Where the FILTER clause shines is that it is easy to combine with other aggregates:
select count(*), -- all
count(myCol), ...
What is the correct way to document a **kwargs parameter?
I'm using sphinx and the autodoc plugin to generate API documentation for my Python modules. Whilst I can see how to nicely document specific parameters, I cannot find an example of how to document a **kwargs parameter.
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postgresql port confusion 5433 or 5432?
I have installed postgresql on OSX. When I run psql, I get
7 Answers
7
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Heatmap in matplotlib with pcolor?
..."http://datasets.flowingdata.com/ppg2008.csv")
nba = pd.read_csv(page, index_col=0)
# Normalize data columns
nba_norm = (nba - nba.mean()) / (nba.max() - nba.min())
# Sort data according to Points, lowest to highest
# This was just a design choice made by Yau
# inplace=False (default) ->thanks ...
How to merge lists into a list of tuples?
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@Adrien: cheers for your applicable comment. For Python 2.x, s/zip_longest()/izip_longest(). Renamed in Python 3.x to zip_longest().
– mechanical_meat
Jul 10 '11 at 19:13
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How to wait in a batch script? [duplicate]
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You can ping an address that surely doesn't exist and specify the desired timeout:
ping 192.0.2.2 -n 1 -w 10000 > nul
And since the address does not exists, it'll wait 10,000 ms (10 seconds) and returns.
The -w 10000 part specifies the desired timeout in millise...
How to make connection to Postgres via Node.js
.../usr/local/pgsql/data now how can I interact with this through node? For example, what would the connectionstring be, or how am I able to find out what it is.
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Why are Python's 'private' methods not actually private?
...rscores to the name, like this: __myPrivateMethod() . How, then, can one explain this
12 Answers
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How many double numbers are there between 0.0 and 1.0?
...it fraction; between any two adjacent powers of two (inclusive of one and exclusive of the next one), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 of them). For example, that's the number of distinct doubles between 0.5 included and 1.0 excluded, and exactly...