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How to use arguments from previous command?
...w see:
$ echo a
without pressing Enter yet, do the following
Press Alt-3 Alt-Ctrl-y
Press Alt-- 2 Alt-Ctrl-y
Now you will see:
$ echo ace
By the way, you could have put the echo on the line by selecting argument 0:
Press Alt-0 Alt-Ctrl-y
Edit:
To answer the question you added to your or...
Reshaping data.frame from wide to long format
...:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
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Reading binary file and looping over each byte
...
396
Python 2.4 and Earlier
f = open("myfile", "rb")
try:
byte = f.read(1)
while byte != "...
How to display unique records from a has_many through relationship?
...ay to display unique records from a has_many, through relationship in Rails3.
4 Answers
...
What is the significance of ProjectTypeGuids tag in the visual studio project file
...
3 Answers
3
Active
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Python integer division yields float
...
Take a look at PEP-238: Changing the Division Operator
The // operator will be available to request floor division unambiguously.
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How to tell Maven to disregard SSL errors (and trusting all certs)?
...
239
You can disable SSL certificate checking by adding one or more of these command line parameters...
What is the difference between an expression and a statement in Python?
...duced to some kind of "value", which can be any Python object. Examples:
3 + 5
map(lambda x: x*x, range(10))
[a.x for a in some_iterable]
yield 7
Statements (see 1, 2), on the other hand, are everything that can make up a line (or several lines) of Python code. Note that expressions are stateme...
What are the differences between vector and list data types in R?
...tors are "atomic vectors" in strict R parlance:
aaa <- vector("list", 3)
is.list(aaa) #TRUE
is.vector(aaa) #TRUE
Lists are a "recursive" type (of vector) whereas atomic vectors are not:
is.recursive(aaa) # TRUE
is.atomic(aaa) # FALSE
You process data objects with different functions...
How can I confirm a database is Oracle & what version it is using SQL?
...---------------------------------------
Oracle Database 10g Release 10.2.0.3.0 - 64bit Production
PL/SQL Release 10.2.0.3.0 - Production
CORE 10.2.0.3.0 Production
TNS for Solaris: Version 10.2.0.3.0 - Production
NLSRTL Version 10.2.0.3.0 - Production
...