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How do I make a list of data frames?
How do I make a list of data frames and how do I access each of those data frames from the list?
8 Answers
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Why do enum permissions often have 0, 1, 2, 4 values?
Why are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ?
7 Answers
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Which is faster: while(1) or while(2)?
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jmp .L2
.seh_endproc
.ident "GCC: (tdm64-2) 4.8.1"
With -O2 and -O3 (same output):
.file "main.c"
.intel_syntax noprefix
.def __main; .scl 2; .type 32; .endef
.section .text.startup,"x"
.p2align 4,,15
.globl main
.def main; .scl 2; ....
In Ruby, is there an Array method that combines 'select' and 'map'?
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I usually use map and compact together along with my selection criteria as a postfix if. compact gets rid of the nils.
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}
=> [3, 3, 3, nil, nil, nil]
jruby-1.5.0 > [1,1,1,2,3,4].m...
Generate a random point within a circle (uniformly)
I need to generate a uniformly random point within a circle of radius R .
21 Answers
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Where can I find the TypeScript version installed in Visual Studio?
Maybe it's obvious, but I checked everywhere (besides the right place) and googled it. Nothing.
14 Answers
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Difference between map, applymap and apply methods in Pandas
...rame’s apply method does exactly this:
In [116]: frame = DataFrame(np.random.randn(4, 3), columns=list('bde'), index=['Utah', 'Ohio', 'Texas', 'Oregon'])
In [117]: frame
Out[117]:
b d e
Utah -0.029638 1.081563 1.280300
Ohio 0.647747 0.831136 -1.549481
Tex...
Adding a column to a data.frame
...xt, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, ...
What would cause an algorithm to have O(log n) complexity?
My knowledge of big-O is limited, and when log terms show up in the equation it throws me off even more.
6 Answers
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Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
...which I can clean a database in SQl Server 2005 by dropping all the tables and deleting stored procedures, triggers, constraints and all the dependencies in one SQL statement?
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