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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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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)...
Is it safe to check floating point values for equality to 0?
...ality between double or decimal type values normally, but I'm wondering if 0 is a special case.
9 Answers
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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...
How to create a UIView bounce animation?
...r alloc] initWithItems:@[self.redSquare]];
elasticityBehavior.elasticity = 0.7f;
[self.animator addBehavior:elasticityBehavior];
And here are the results
UIKit Dynamics is a really powerful and easy to use addition to iOS7 and you can get some great looking UI from it.
Other examples:
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How to linebreak an svg text within javascript?
... occur, you can break your text into multiple <tspan>s, each with x="0" and dy="1.4em" to simulate actual lines of text. For example:
<g transform="translate(123 456)"><!-- replace with your target upper left corner coordinates -->
<text x="0" y="0">
<tspan x="0" dy...
Should I return EXIT_SUCCESS or 0 from main()?
...eing conflicting answers: should the main routine of a C++ program return 0 or EXIT_SUCCESS ?
8 Answers
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Calling a Method From a String With the Method's Name in Ruby
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answered Sep 10 '09 at 20:17
Colin GravillColin Gravill
3,85311 gold badge1818 silver badges1616 bronze badges
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How to smooth a curve in the right way?
...bove.
import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0,2*np.pi,100)
y = np.sin(x) + np.random.random(100) * 0.2
yhat = savitzky_golay(y, 51, 3) # window size 51, polynomial order 3
plt.plot(x,y)
plt.plot(x,yhat, color='red')
plt.show()
UPDATE: It has come to my attention t...
What's the point of malloc(0)?
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According to the specifications, malloc(0) will return either "a null pointer or a unique pointer that can be successfully passed to free()".
This basically lets you allocate nothing, but still pass the "artist" variable to a call to free() without worry. For pra...