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Logic to test that 3 of 4 are True
... (§4.7/4) indicates that converting bool to int gives the expected values 0 or 1.
In Java and C#, you can use the following construct:
if ((a?1:0) + (b?1:0) + (c?1:0) + (d?1:0) == 3)
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Creating a zero-filled pandas data frame
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You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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How to use Active Support core extensions
I have Active Support 3.0.3 installed and Rails 3.0.3 with Ruby 1.8.7.
5 Answers
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Using bitwise OR 0 to floor a number
...egers only
Odd Comparative behavior: Math.floor(NaN) === NaN, while (NaN | 0) === 0
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Which method performs better: .Any() vs .Count() > 0?
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edited Nov 20 '08 at 12:51
answered Nov 20 '08 at 12:37
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Is there any boolean type in Oracle databases?
...read on asktom. From recommending CHAR(1) 'Y'/'N' they switch to NUMBER(1) 0/1 when someone points out that 'Y'/'N' depends on the English language, while e.g. German programmers might use 'J'/'N' instead.
The worst thing is that they defend this stupid decision just like they defend the ''=NULL st...
How can I easily view the contents of a datatable or dataview in the immediate window
...Set, expand the quick watch, view the Tables, expand that, then view Table[0] (for example). You will see something like {Table1} in the quick watch, but notice that there is also a magnifying glass icon. Click on that icon and your DataTable will open up in a grid view.
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How to format strings in Java
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In addition to String.format, also take a look java.text.MessageFormat. The format less terse a...
MFC CListCtrl使用方法详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
....microsoft.com/library/default.asp?url=/library/en-us/wceshellui5/html/wce50lrflistviewstyles.asp
3. 插入数据
m_list.InsertColumn( 0, "ID", LVCFMT_LEFT, 40 ); //插入列
m_list.InsertColumn( 1, "NAME", LVCFMT_LEFT, 50 );
int nRow = m_list.InsertItem(0, "11"); //插...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...