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Integrate ZXing in Android Studio
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234
I was integrating ZXING into an Android application and there were no good sources for the inpu...
How to initialize all members of an array to the same value in Swift?
...ue like this:
With old Swift version:
var threeDoubles = [Double](count: 3, repeatedValue: 0.0)
Since Swift 3.0:
var threeDoubles = [Double](repeating: 0.0, count: 3)
which would give:
[0.0, 0.0, 0.0]
share
...
Pandas dataframe get first row of each group
...;> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6...
Read user input inside a loop
...
answered Jul 30 '11 at 13:42
dankdank
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...
Pass a variable into a partial, rails 3?
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237
Try this:
<% @posts.each do |post| %>
<%= render 'middle', :post => post %>
&...
Should I use encoding declaration in Python 3?
Python 3 uses UTF-8 encoding for source-code files by default. Should I still use the encoding declaration at the beginning of every source file? Like # -*- coding: utf-8 -*-
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Scala: what is the best way to append an element to an Array?
...
3 Answers
3
Active
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How to add a new row to an empty numpy array
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237
The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty ...
Python pandas Filtering out nan from a data selection of a column of strings
...NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob NaN NaN
5 lob NaN NaN
[5 rows x 3 columns]
In [89]:
nms = nms.dropna(thresh=2)
In [90]:
nms[nms.name.notnull()]
Out[90]:
movie name rating
0...