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What is :: (double colon) in Python when subscripting sequences?
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10 Answers
10
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Python assigning multiple variables to same value? list behavior
...y the behavior, I expect to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
9 Answers
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Regular expression for floating point numbers
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TL;DR
Use [.] instead of \. and [0-9] instead of \d to avoid escaping issues in some languages (like Java).
Thanks to the nameless one for originally recognizing this.
One relatively simple pattern for matching a floating point number is
[+-]?([0-9]*[.])...
Numpy: Get random set of rows from 2D array
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200
>>> A = np.random.randint(5, size=(10,3))
>>> A
array([[1, 3, 0],
[3, ...
Suppress warning CS1998: This async method lacks 'await'
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107
I've got an interface with some async functions.
Methods returning Task, I believe. async ...
Integrate ZXing in Android Studio
...ependencies {
implementation 'com.journeyapps:zxing-android-embedded:3.0.2@aar'
implementation 'com.google.zxing:core:3.2.0'
}
and Gradle does all the magic to compile the code and makes it accessible in your app.
To start the Scanner afterwards, use this class/method:
From the Activity:
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
... compares the numbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/html_nod...
Delete the first three rows of a dataframe in pandas
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edited Oct 17 '18 at 1:06
Acumenus
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answered...
Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data fr...
Finding local IP addresses using Python's stdlib
How can I find local IP addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?
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