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How to delete a row by reference in data.table?
... is all i care about here. something like this:
DT = data.table(col1 = 1:1e6)
cols = paste0('col', 2:100)
for (col in cols){ DT[, (col) := 1:1e6] }
keep.idxs = sample(1e6, 9e5, FALSE) # keep 90% of entries
DT.subset = data.table(col1 = DT[['col1']][keep.idxs]) # this is the subsetted table
for (col...
How do you enable “Enable .NET Framework source stepping”?
...ll say "built by: RTMGDR". Note the version number (for example 4.0.30319.269 built by: RTMGDR)
Now, we want to find the update that created this version. Do this by searching for the dll and version number at support.microsoft.com/kb/
For example, I did the following google search:
site:support.m...
C++并发编程（中文版） - 文档下载 - 清泛网 - 专注C/C++及内核技术
...… 266
9.3 总结… 268
第10章 多线程应用的测试和调试… 269
10.1 与并发相关的错误类型… 269
10.1.1 不必要的阻塞… 269
10.2 定位并发相关的错误的测试和调试技巧… 271
10.2.1 检阅代码定位潜在错误… 271
10.2.2 通过测试定位并行...
How to get the current time in milliseconds from C in Linux?
...LTIME, &spec);
s = spec.tv_sec;
ms = round(spec.tv_nsec / 1.0e6); // Convert nanoseconds to milliseconds
if (ms > 999) {
s++;
ms = 0;
}
printf("Current time: %"PRIdMAX".%03ld seconds since the Epoch\n",
(intmax_t)s, ms);
}
If your goal is to...
How does lombok work?
...
It uses JSR 269 Pluggable Annotation Processing API available in Java 6.
Note that lombok.jar contains a file named /META-INF/services/javax.annotation.processing.Processor. When javac sees this file in a compilation classpath, it runs ...
Moving average or running mean
...n with only 100,000 points
np.random.seed(42)
x = np.random.randn(100000)+1e6
y1 = running_mean_convolve(x, 10)
y2 = running_mean_cumsum(x, 10)
assert np.allclose(y1, y2, rtol=1e-12, atol=0)
the more points you accumulate over the greater the floating point error (so 1e5 points is noticable, 1e6 ...
Get characters after last / in url
...
269
Very simply:
$id = substr($url, strrpos($url, '/') + 1);
strrpos gets the position of the l...
What is difference between Collection.stream().forEach() and Collection.forEach()?
... 10 100 1000 10000
iterator.forEach 95 192 2076 19269 198519
for:each 157 224 2492 25466 248494
for with index 140 368 2084 22294 207092
iterable.stream.forEach 946 687 2206 21697 238457
Java 11 Hotspot VM - 2.8GHz AM...
Angular.js ng-repeat across multiple tr's
...rid_ko tr:nth-child(odd)>td{background-color:#f3f3f3;border-color:#fff #e6e6e6 #e6e6e6 #fff}
#tablegrid_ko tr:nth-child(even)>td{background-color:#ddd;border-color:#eaeaea #d0d0d0 #d0d0d0 #eaeaea}
div.scrollable-table-wrapper{
background:#268;border:1px solid #268;
display:inline-block;height...
Downloading Java JDK on Linux via wget is shown license page instead
...http://download.oracle.com/otn-pub/java/jdk/11+28/55eed80b163941c8885ad9298e6d786a/jdk-11_linux-x64_bin.tar.gz
UPDATED FOR JDK 10.0.2
wget --no-check-certificate -c --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/10.0.2+13/19aef61b38124481863b...