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Given an emacs command name, how would you find key-bindings ? (and vice versa)
...ble. Key-maps are kept in variables, however the key codes are stored in a raw format. Try C-h v isearch-mode-map for an example.
For more help on getting help, you can type
C-h ?
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improv...
Extracting text OpenCV
....CHAIN_APPROX_NONE)
mask = np.zeros(bw.shape, dtype=np.uint8)
for idx in range(len(contours)):
x, y, w, h = cv2.boundingRect(contours[idx])
mask[y:y+h, x:x+w] = 0
cv2.drawContours(mask, contours, idx, (255, 255, 255), -1)
r = float(cv2.countNonZero(mask[y:y+h, x:x+w])) / (w * h)
...
How to loop through file names returned by find?
...
You should use the -r option to read: -r raw input - disables interpretion of backslash escapes and line-continuation in the read data
– Daira Hopwood
Jan 17 '15 at 0:45
...
What's the opposite of chr() in Ruby?
... 1.9.x - 2.1.x portable replacements:
[22] pry(main)> "\u0221".ord.chr
RangeError: 545 out of char range
from (pry):2:in 'chr'
[23] pry(main)> x = "\u0221".unpack('U')[0]
=> 545
[24] pry(main)> [x].pack('U')
=> "ȡ"
[25] pry(main)>
...
How to un-submodule a Git submodule?
... Bash 2.20.1.1 on Windows 10 with latest version from github: curl https://raw.githubusercontent.com/jeremysears/scripts/master/bin/git-submodule-rewrite > git-submodule-rewrite.sh and ./git-submodule-rewrite.sh <submodule-name>
– Alexey
Dec 6 '19 at 1...
What is “Argument-Dependent Lookup” (aka ADL, or “Koenig Lookup”)?
...unfortunate behavior.
ADL is responsible for a major overhaul of the for-range loop in C++11. To understand why ADL can sometimes have unintended effects, consider that not only the namespaces where the arguments are defined are considered, but also the arguments of template arguments of the argum...
What is in your Mathematica tool bag? [closed]
...the z-axis
In[2] := rots = RotationTransform[#, {0, 0, 1}] & /@ (Pi/2 Range[0, 3]);
Using SelectEquivalents we can group the points that produce the same set of images under these operations, i.e. they're equivalent, using the following
In[3] := SelectEquivalents[ pts, Union[Through[rots[#] ...
How can I get a count of the total number of digits in a number?
...
If your number range includes negatives, you'll need to use Math.Floor(Math.Log10(Math.Abs(n)) + 1);
– mrcrowl
Jun 6 '12 at 3:35
...
Parse rfc3339 date strings in Python? [duplicate]
...since it requires the caller to provide format strings for the rather wide range of ISO 8601 variants (unless one likes ValueError if the seconds are omitted, e.g). The dateutil parser, on the other hand, handles these much better.
– Alex North-Keys
Apr 25 '17...
How to iterate over rows in a DataFrame in Pandas
...n make arbitrarily complex things work through the simplicity and speed of raw Python code.
Caveats
List comprehensions assume that your data is easy to work with - what that means is your data types are consistent and you don't have NaNs, but this cannot always be guaranteed.
The first one is more...