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Why does direction of index matter in MongoDB?
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edited Apr 21 '13 at 18:09
shlensky
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Select statement to find duplicates on certain fields
...ore information on how to delete the rows.
http://support.microsoft.com/kb/139444
There should be a criterion for deciding how you define "first rows" before you use the approach in the link above. Based on that you'll need to use an order by clause and a sub query if needed. If you can post some sa...
rotating axis labels in R
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doncherry
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answered Dec 1 '09 at 20:56
ShaneShane
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How to switch position of two items in a Python list?
...erk Güder
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Remove duplicated rows using dplyr
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139
Note: dplyr now contains the distinct function for this purpose.
Original answer below:
li...
Subscripts in plots in R
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138
expression is your friend:
plot(1,1, main=expression('title'^2)) #superscript
plot(1,1, main...
Append column to pandas dataframe
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135
It seems in general you're just looking for a join:
> dat1 = pd.DataFrame({'dat1': [9,5]})...
How to find the length of a string in R
... min lq median uq max neval
nchar(x) 11.868 12.776 13.1590 13.6475 41.815 100
str_length(x) 30.715 33.159 33.6825 34.1360 173.400 100
stri_length(x) 2.653 3.281 4.0495 4.5380 19.966 100
and also works fine with NA's
nchar(NA)
## [1] 2
stri_length(NA)
## [1] ...
What does “@@ -1 +1 @@” mean in Git's diff output?
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Todd A. JacobsTodd A. Jacobs
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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
... 块设备 109
第四部分 文件和目录、文件系统、管道 133
第五部分 面向字符的特殊文件 181
下篇 莱昂氏UNIX源代码分析
前言 207
第1章 绪论 209
1.1 UNIX操作系统 209
1.2 公用程序 209
1.3 其他文档 210
1.4 UNIX程序员手...