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PostgreSQL: Difference between text and varchar (character varying)
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There is no difference, under the hood it's all varlena (variable length array).
Check this article from Depesz: http://www.depesz.com/index.php/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/
A couple of highlights:
To sum it all up:
char(n) – takes t...
How to round a number to n decimal places in Java
...ues into account. Floating point values have a binary representation internally. That means that a value like 2.7735 does not actually have that exact value internally. It can be slightly larger or slightly smaller. If the internal value is slightly smaller, then it will not round up to 2.7740. To r...
pandas: filter rows of DataFrame with operator chaining
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That is a really nice solution - I wasn't even aware that you could jury-rig methods like that in python. A function like this would be really nice to have in Pandas itself.
– naught101
Mar 3 '17 at...
Python: How would you save a simple settings/config file?
...) as f:
sample_config = f.read()
config = ConfigParser.RawConfigParser(allow_no_value=True)
config.readfp(io.BytesIO(sample_config))
# List all contents
print("List all contents")
for section in config.sections():
print("Section: %s" % section)
for options in config.options(section):
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Java logical operator short-circuiting
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In fact, to be really complete, all of &&, ||, & and | evaluate left to right. For a set of booleans b1, b2, ..., bn, the short circuit versions will cease evaluation when the first of these booleans is true (||) or false (&&a...
How to create a directory if it doesn't exist using Node.js?
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using *Sync methods is usually a no-no: don't want to block the event loop
– Max Heiber
Feb 13 '17 at 21:23
16
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JavaScript function similar to Python range()
...uple of additional defensive checks - ensure that the arguments passed are all coercible to numbers and ensure that stop is greater than start (and swap them if not).
– Russ Cam
Nov 25 '11 at 18:46
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How to assert two list contain the same elements in Python? [duplicate]
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Thanks. But downright misleading, I would have called it!
– Wild Pottok
Oct 22 '18 at 16:18
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Git: fatal: Pathspec is in submodule
I'm trying to get TravisCI to automatically deploy my Hakyll static site, according to this guide .
5 Answers
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Character reading from file in Python
... print repr(line)
It's also possible to open files in update mode, allowing both reading and writing:
with codecs.open('test', encoding='utf-8', mode='w+') as f:
f.write(u'\u4500 blah blah blah\n')
f.seek(0)
print repr(f.readline()[:1])
EDIT: I'm assuming that your intended go...