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Python: avoid new line with print command [duplicate]
...ork on 3.x, you suppress using print('whateverhere', end='') where end normally defaults to '\n'
– Jon Clements♦
Jun 29 '12 at 17:19
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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
How can I get a precise time, for example in milliseconds in Objective-C?
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Actually this is precise enough for the general use case.
– logancautrell
Jul 2 '12 at 12:30
4
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When should I use the Visitor Design Pattern? [closed]
...want to make the fewest possible modifications to it.
The Visitor pattern allows you to move each new operation in a suitable class, and you need to extend the hierarchy's interface only once. Let's do it. First, we define an abstract operation (the "Visitor" class in GoF) which has a method for ev...
INSERT INTO…SELECT for all MySQL columns
... syntax, it looks like this (leave out the column list to implicitly mean "all")
INSERT INTO this_table_archive
SELECT *
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00'
For avoiding primary key errors if you already have data in the archive table
INSERT INTO this_table_archive
SELECT...
What is the syntax rule for having trailing commas in tuple definitions?
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In all cases except the empty tuple the comma is the important thing. Parentheses are only required when required for other syntactic reasons: to distinguish a tuple from a set of function arguments, operator precedence, or to a...
Django TemplateDoesNotExist?
... assuming that you have the apps configured in settings.py like this:
INSTALLED_APPS = (
'appname1',
'appname2',
'appname3',
)
By default Django will load the templates under templates/ directory under every installed apps. So with your directory structure, we want to move our templat...
Installing Python 3 on RHEL
I'm trying to install python3 on RHEL using the following steps:
19 Answers
19
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What is your preferred style for naming variables in R? [closed]
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Good previous answers so just a little to add here:
underscores are really annoying for ESS users; given that ESS is pretty widely used you won't see many underscores in code authored by ESS users (and that set includes a bunch of R Core as well as CRAN authors, excptions like Hadley notwithsta...
SqlAlchemy - Filtering by Relationship Attribute
...ts = Patient.query.filter(Patient.mother.has(phenoscore=10))
or join (usually faster):
patients = Patient.query.join(Patient.mother, aliased=True)\
.filter_by(phenoscore=10)
share
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