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How do I get SUM function in MySQL to return '0' if no values are found?
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307
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
T...
Is there a way to list pip dependencies/requirements?
...m providing an updated answer.
This was tested with pip versions 8.1.2, 9.0.1, 10.0.1, and 18.1.
To get the output without cluttering your current directory on Linux use
pip download [package] -d /tmp --no-binary :all: -v
-d tells pip the directory that download should put files in.
Better, ju...
How to get different colored lines for different plots in a single figure?
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E.g.:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt...
How do I catch a numpy warning like it's an exception (not just for testing)?
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205
It seems that your configuration is using the print option for numpy.seterr:
>>> impo...
Scaling Node.js
...like to know what the general principles are for scaling node up to, say, 20 queries per second.
1 Answer
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How to append rows to an R data frame
...sive insight than system.time:
library(microbenchmark)
microbenchmark(f1(1000), f3(1000), f4(1000), times = 5)
# Unit: milliseconds
# expr min lq median uq max neval
# f1(1000) 1024.539618 1029.693877 1045.972666 1055.25931 1112.769176 5
# f3(1000) ...
Case preserving substitute in Vim
...toMark Lodato
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16
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Could not load file or assembly 'Newtonsoft.Json, Version=4.5.0.0, Culture=neutral, PublicKeyToken=3
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240
In package manager console execute: Update-Package –reinstall Newtonsoft.Json.
UPDATE
I orig...
Programmatically create a UIView with color gradient
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702
Objective-C:
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 50)];
CAGradie...