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Dynamically select data frame columns using $ and a character value
... a reproducible example below:
# set seed for reproducibility
set.seed(123)
df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. Sec...
pandas: How do I split text in a column into multiple rows?
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This splits the Seatblocks by space and gives each its own row.
In [43]: df
Out[43]:
CustNum CustomerName ItemQty Item Seatblocks ItemExt
0 32363 McCartney, Paul 3 F04 2:218:10:4,6 60
1 31316 Lennon, John 25 F01 1:13:36:1...
Logic to test that 3 of 4 are True
I want to return True if and only if 3 out of 4 boolean values are true.
27 Answers
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Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
I have a string that is up to 3 characters long when it's first created in SQL Server 2008 R2.
17 Answers
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How can I index a MATLAB array returned by a function without first assigning it to a local variable
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386
It actually is possible to do what you want, but you have to use the functional form of the in...
How to remove element from an array in JavaScript?
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355
For a more flexible solution, use the splice() function. It allows you to remove any item in ...
Maven Install on Mac OS X
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OS X prior to Mavericks (10.9) actually comes with Maven 3 built in.
If you're on OS X Lion, you won't have java installed by default. Just run java by itself and it'll prompt you to install it.
Assuming qualifications are met, run mvn -version and see some output like this:
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How do I change Bootstrap 3 column order on mobile layout?
...ith a top fixed navbar. Underneath I have two columns, one for a sidebar (3), and one for content (9). Which on desktop looks like this
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C++ preprocessor __VA_ARGS__ number of arguments
....) \
PP_ARG_N(__VA_ARGS__)
#define PP_ARG_N( \
_1, _2, _3, _4, _5, _6, _7, _8, _9,_10, \
_11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
_21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
_31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \
_41,_42,_43,_44,_45,_46,_47...
Convert a row of a data frame to vector
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edited Oct 30 '19 at 16:15
answered Jan 23 '13 at 16:42
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