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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
... (4). In particular, (3) applies directly to the code I have above: if you transform the declaration of MAP to:
public static volatile HashMap<Object, Object> MAP;
then everything is kosher: readers who see a non-null value necessarily have a happens-before relationship with the store to MA...
Cluster analysis in R: determine the optimal number of clusters
...ges("bclust")
library(bclust)
x <- as.matrix(d)
d.bclus <- bclust(x, transformed.par = c(0, -50, log(16), 0, 0, 0))
viplot(imp(d.bclus)$var); plot(d.bclus); ditplot(d.bclus)
dptplot(d.bclus, scale = 20, horizbar.plot = TRUE,varimp = imp(d.bclus)$var, horizbar.distance = 0, dendrogram.lwd = 2)
...
How to prove that a problem is NP complete?
... time)
Select a known NP-complete problem L'
Describe an algorithm f that transforms L' into L
Prove that your algorithm is correct (formally: x ∈ L' if and only if f(x) ∈ L )
Prove that algo f runs in polynomial time
...
Best practices for exception management in Java or C# [closed]
...exceptions, or
you would have to catch exception D in
the new foo, and transform the D into
an A, B, or C.
Bill Venners: But aren't you breaking
their code in that case anyway, even
in a language without checked
exceptions? If the new version of foo
is going to throw a new excepti...
Can dplyr package be used for conditional mutating?
...| c==4, 3L, NA_integer_)))
}
BASE_fun <- function(DF) { # R v3.1.0
transform(DF, g = ifelse(a %in% c(2,5,7) | (a==1 & b==4), 2L,
ifelse(a %in% c(0,1,3,4) | c==4, 3L, NA_integer_)))
}
system.time(ans1 <- DT_fun(DT))
# user system elapsed
# 2.659 0.420 3.107
sys...
Interface Builder: What are the UIView's Layout iOS 6/7 Deltas for?
...orking with. If you're editing for iOS 6, the deltas there are in order to transform the element correctly for iOS 7 (the reverse of the example above).
In order to view the different styles, you can change the way Interface Builder presents it based on the OS it would be running on. This is contai...
Moving matplotlib legend outside of the axis makes it cutoff by the figure box
...', bbox_to_anchor=(0.5,-0.1))
text = ax.text(-0.2,1.05, "Aribitrary text", transform=ax.transAxes)
ax.set_title("Trigonometry")
ax.grid('on')
fig.savefig('samplefigure', bbox_extra_artists=(lgd,text), bbox_inches='tight')
This produces:
[edit] The intent of this question was to completely avoid...
What is the difference between a string and a byte string?
...the browser in UTF-8 encoding) and display the string.
In python3, you can transform string and byte string to each other:
>>> print('中文'.encode('utf-8'))
b'\xe4\xb8\xad\xe6\x96\x87'
>>> print(b'\xe4\xb8\xad\xe6\x96\x87'.decode('utf-8'))
中文
In a word, string is for displa...
ASP.NET Web Site or ASP.NET Web Application?
...iles.
Another nice feature introduced in Visual Studio 2010 is Web.config transformation. This is also not available in Web Sites. Now works with Web Sites in VS 2013.
Building a Web Application is faster than building a Web Site, specially for large sites. This is mainly because Web Applications ...
Is mathematics necessary for programming? [closed]
...rd year Calculus(Diff EQ, volume integrations, Series, Fourier and Laplace transforms) and a Numerical Analysis course.
I find that my math is incredibly lacking for computer programming. There are entire areas of Discrete math and logic that I am missing, and I only survive due to an extensive li...