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postgresql - add boolean column to table set default
... into steps:
ALTER TABLE users ADD COLUMN priv_user BOOLEAN;
UPDATE users SET priv_user = 'f';
ALTER TABLE users ALTER COLUMN priv_user SET NOT NULL;
ALTER TABLE users ALTER COLUMN priv_user SET DEFAULT FALSE;
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How to avoid overflow in expr. A * B - C * D
... +1 You're the only one to notice this. The only tricky part is setting the compiler to do wrap-around overflow and checking if the correct result actually does fit into a long long.
– Mysticial
Nov 5 '12 at 18:27
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What is “point free” style (in Functional Programming)?
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Retrieve database or any other file from the Internal Storage using run-as
On a non-rooted android device, I can navigate to the data folder containing the database using the run-as command with my package name. Most files types I am content with just viewing, but with the database I would like to pull if from the android device.
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OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
...esponsible to iterate on every channel of the image. For instance, you can set it to iterate on only one channel :) Don't forget to up vote.
– karlphillip
Nov 27 '12 at 17:45
3
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Is there a difference between x++ and ++x in java?
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1: istore_1 // Pop the value on top of the operand stack (`2`) and set the
// value of the local variable at index `1` (`y`) to this value.
2: iload_1 // Push the value (`2`) of the local variable at index `1` (`y`)
// onto the operand stack
3: ...
How do I select elements of an array given condition?
...'],
dtype='|S1')
And equivalent way to do this is with np.all() by setting the axis argument appropriately.
>>> output = y[np.all([x > 1, x < 5], axis=0)] # desired output is ['o','o','a']
>>> output
array(['o', 'o', 'a'],
dtype='|S1')
by the numbers:
>&g...
EOL conversion in notepad ++
...on for even quicker finding (or different language versions)
You can also set the default EOL in notepad++ via "Settings" -> "Preferences" -> "New Document/Default Directory" then select "Unix/OSX" under the Format box.
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How do I keep track of pip-installed packages in an Anaconda (Conda) environment?
...ges that were either installed using the pip installer itself or they used setuptools in their setup.py so conda build generated the egg information. So you have basically three options.
You can take the union of the conda list and pip freeze and manage packages that were installed using conda (th...
np.mean() vs np.average() in Python NumPy?
...verage do not take in account masks, so compute the average over the whole set of data.
mean takes in account masks, so compute the mean only over unmasked values.
g = [1,2,3,55,66,77]
f = np.ma.masked_greater(g,5)
np.average(f)
Out: 34.0
np.mean(f)
Out: 2.0
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