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Can I install Python 3.x and 2.x on the same Windows computer?
... run a program on the command line. Will this break if I install a 2.x and 3.x version of Python on the same machine?
20 An...
How to store standard error in a variable
...
93
It would be neater to capture the error file thus:
ERROR=$(</tmp/Error)
The shell recogniz...
Frequency table for a single variable
...
153
Maybe .value_counts()?
>>> import pandas
>>> my_series = pandas.Series([1,2,2...
If vs. Switch Speed
...
answered Jan 14 '09 at 23:16
Konrad RudolphKonrad Rudolph
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What is the optimal Jewish toenail cutting algorithm?
...mport ifilter, permutations
validseqs = ifilter(isValid, permutations([1,2,3,4,5]))
for i in validseqs:
print i
(1, 3, 5, 2, 4)
(1, 4, 2, 5, 3)
(2, 4, 1, 3, 5)
(2, 4, 1, 5, 3)
(2, 5, 3, 1, 4)
(3, 1, 4, 2, 5)
(3, 1, 5, 2, 4)
(3, 5, 1, 4, 2)
(3, 5, 2, 4, 1)
(4, 1, 3, 5, 2)
(4, 2, 5, 1, 3)
(4, 2, ...
How to join two sets in one line without using “|”
...
320
You can use union method for sets: set.union(other_set)
Note that it returns a new set i.e it...
Maven dependency for Servlet 3.0 API?
How can I tell Maven 2 to load the Servlet 3.0 API?
10 Answers
10
...
How to select the row with the maximum value in each group
...t]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
If you'd like just the first max value of pt:
group[group[, .I[which.max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
In this case, it ...
Optional Parameters with C++ Macros
...S(message, size) PrintString(message, size, 0)
#define PRINT_STRING_3_ARGS(message, size, style) PrintString(message, size, style)
#define GET_4TH_ARG(arg1, arg2, arg3, arg4, ...) arg4
#define PRINT_STRING_MACRO_CHOOSER(...) \
GET_4TH_ARG(__VA_ARGS__, PRINT_STRING_3_ARGS, \
...
莱昂氏unix源代码分析 PDF - 文档下载 - 清泛网 - 专注C/C++及内核技术
...篇 UNIX操作系统版本6源代码
UNIX操作系统过程分类索引 3
UNIX操作系统文件及过程 5
UNIX操作系统定义的符号列表 7
UNIX操作系统源代码交叉引用列表 9
第一部分 初始化、进程初始化 25
第二部分 陷入、中断、系统调用和
...