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How to take column-slices of dataframe in pandas
...th the following columns:
foo, bar, quz, ant, cat, sat, dat.
# selects all rows and all columns beginning at 'foo' up to and including 'sat'
df.loc[:, 'foo':'sat']
# foo bar quz ant cat sat
.loc accepts the same slice notation that Python lists do for both row and columns. Slice notation being...
An algorithm for inflating/deflating (offsetting, buffering) polygons
...re written in Delphi, C++ and C#. It has a very unencumbered Boost license allowing it to be used in both freeware and commercial applications without charge.
Polygon offsetting can be performed using one of three offset styles - squared, round and mitered.
...
How do I delete all untracked files from my working directory in Mercurial?
Is it possible to delete all untracked files from my working directory? Let's say I added a bunch of files to my working directory, didn't add them via 'hg add' and now want to get rid of those new files entirely?
...
Showing line numbers in IPython/Jupyter Notebooks
...l line numbers. In more recent notebook versions Shift-L should toggle for all cells.
If you can't remember the shortcut, bring up the command palette Ctrl-Shift+P (Cmd+Shift+P on Mac), and search for "line numbers"), it should allow to toggle and show you the shortcut.
...
Get all table names of a particular database by SQL query?
... Server and MySQL 2) INFORMATION_SCHEMA.TABLES exists only in MySQL 3) I really wonder how comes you got so many upvotes for this ...
– Apostolos
Dec 14 '18 at 11:04
...
What can you use Python generator functions for?
...in them. I want to know what types of problems that these functions are really good at solving.
16 Answers
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Is optimisation level -O3 dangerous in g++?
...n undefined behavior, due to relying more strictly on the rules, and especially corner cases, of the language(s).
As a personal note, I am running production software in the financial sector for many years now with -O3 and have not yet encountered a bug that would not have been there if I would hav...
Use email address as primary key?
...u store is going to take up space in RAM.
– Jonathan Allen
Mar 11 '15 at 8:40
In case any one wonders, as I did, a GUI...
How do I add files without dots in them (all extension-less files) to the gitignore file?
...**/
!*.*
That gitignore exclusion rule (a negated pattern) should ignore all files, except the ones with an extension.
As mentioned below by Mad Physicist, the rule is:
It is not possible to re-include a file if a parent directory of that file is excluded. (*)
(*: unless certain conditions are m...
CSS image resize percentage of itself?
...img.fake is the same image.
Browser support note: This method will work in all browsers, because all browsers support css properties used in method.
The method works in this way:
#wrap and #wrap img.fake have flow
#wrap has overflow: hidden so that its dimensions are identical to inner image (img.f...