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Pandas read_csv low_memory and dtype options
...etermine what dtype a column should have once the whole file is read. This means nothing can really be parsed before the whole file is read unless you risk having to change the dtype of that column when you read the last value.
Consider the example of one file which has a column called user_id.
It c...
What is the exact meaning of Git Bash?
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i want to know just meaning about that!
– DRAJI
Jul 24 '13 at 5:10
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Is it smart to replace boost::thread and boost::mutex with c++11 equivalents?
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@Anthony are you sure you don't mean interrupt() for boost::thread? Also it appears that it's an original proposal, which changed since 2007.
– Alex B
Aug 30 '11 at 11:16
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Delete commits from a branch in Git
...t, then this command will wack it...
git reset --hard HEAD~1
The HEAD~1 means the commit before head.
Or, you could look at the output of git log, find the commit id of the commit you want to back up to, and then do this:
git reset --hard <sha1-commit-id>
If you already pushed it, you...
How to develop a soft keyboard for Android? [closed]
...ys (like the
// shift/ctrl/alt)?
// NOTE What does android:keyEdgeFlags do/mean
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Why does Clojure have “keywords” in addition to “symbols”?
...:bar, when the symbol FOO is in the package BAR
For keyword symbols that means that :foo, keyword:foo and keyword::foo are all the same symbol. Thus the latter two notations are usually not used.
So :foo is just parsed to be in the package KEYWORD, assuming that giving no package name before the...
How to debug Lock wait timeout exceeded on MySQL?
...ch the scan are released after the STATEMENT completes.
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This means that in READ COMMITTED other transactions are free to update rows that they would not have been able to update (in REPEATABLE READ) once the UPDATE statement completes.
Therefore: The more restrictive the isolation le...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...meit df["A1"], df["A2"] = calculate(df['a'])
2.65 ms ± 92.4 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
%timeit df["A1"], df["A2"] = zip(*df["a"].apply(calculate))
159 ms ± 5.24 ms per loop (mean ± std. dev. of 7 runs, 10 loops each)
60x faster than zip
In general, avoid usin...
When should I use OWIN Katana?
...the application. OWIN abstracts web servers and framework components. That means that your application code will now be aware of the OWIN interface, but not of the webserver that is serving the request.
In return, applications can be more easily ported between hosts and potentially entire platforms...
Using printf with a non-null terminated string
...t. Specifying a maximum length does not make NULL lose its "end-of-string" meaning for printf.
– DarkDust
Feb 17 '19 at 8:59
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