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How to clone a case class instance and change just one field in Scala?
Let's say I have a case class that represents personas, people on different social networks. Instances of that class are fully immutable, and are held in immutable collections, to be eventually modified by an Akka actor.
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Creating a zero-filled pandas data frame
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Note that you may run into int/float issue if you will be doing something like d.set_value(params) after initializing d to contain 0's. An easy fix is: d = pd.DataFrame(0.0, index=np.arange(len(data)), columns=feature_list).
– ximiki
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How to delete a word and go into insert mode in Vim?
... "a" commands are great in Vim, also try "ci{" inside a {} block, or "ca{" if you also wish to remove the {} characters too. To translate these commands to English to remember them better, try: "change inner { block" and "change a { block".
Documentation at http://vimdoc.sourceforge.net/htmldoc/mo...
How to convert an entire MySQL database characterset and collation to UTF-8?
...ablename CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
Or if you're still on MySQL 5.5.2 or older which didn't support 4-byte UTF-8, use utf8 instead of utf8mb4:
ALTER DATABASE databasename CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE tablename CONVERT TO CHARACTER SET u...
How do I use itertools.groupby()?
...tor to iterate over each individual item in that group.
Here's a slightly different example with the same data, using a list comprehension:
for key, group in groupby(things, lambda x: x[0]):
listOfThings = " and ".join([thing[1] for thing in group])
print(key + "s: " + listOfThings + ".")
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Can enums be subclassed to add new elements?
...it - which defeats the point of an enum being a well-known set of values.
If you could tell us more about how you want to use this, we could potentially suggest alternative solutions.
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impro...
postgresql - replace all instances of a string within text field
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The Regular Expression Way
If you need stricter replacement matching, PostgreSQL's regexp_replace function can match using POSIX regular expression patterns. It has the syntax regexp_replace(source, pattern, replacement [, flags ]).
I will use flags i...
What is the difference between the OAuth Authorization Code and Implicit workflows? When to use each
...rity consideration of implicit flow is that access_code should have short life so it can't be used on server to server. OK, but the refresh token solve this problem. Why we should use an auth_code flow and request access_token by that on server to obtain access_code?
– Mohammad...
Argparse optional positional arguments?
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Use nargs='?' (or nargs='*' if you will need more than one dir)
parser.add_argument('dir', nargs='?', default=os.getcwd())
extended example:
>>> import os, argparse
>>> parser = argparse.ArgumentParser()
>>> parser.add_arg...
Split list into multiple lists with fixed number of elements
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I have a weird question. For the same case if i convert the data to a sequence, I get a Stream Object. Why is that?
– Rakshith
Jun 23 '16 at 10:26
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