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Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...nd places it behind the content of another.
If we have
list1 = [0, 1, 2, 3, 4]
list2 = [5, 6, 7, 8, 9]
Then
list1 + list2
Is the same as
[0, 1, 2, 3, 4] + [5, 6, 7, 8, 9]
Which evaluates to
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Much like
"abdcde" + "fghijk"
Produces
"abdcdefghijk"
...
How can I make pandas dataframe column headers all lowercase?
...x in data.columns]
example:
>>> data = pd.DataFrame({'A':range(3), 'B':range(3,0,-1), 'C':list('abc')})
>>> data
A B C
0 0 3 a
1 1 2 b
2 2 1 c
>>> data.columns = map(str.lower, data.columns)
>>> data
a b c
0 0 3 a
1 1 2 b
2 2 1 c
...
How do I call setattr() on the current module?
...
223
import sys
thismodule = sys.modules[__name__]
setattr(thismodule, name, value)
or, without u...
Error in : object of type 'closure' is not subsettable
....
library(shiny)
reactive_df <- reactive({
data.frame(col1 = c(1,2,3),
col2 = c(4,5,6))
})
While we often work with reactive expressions in shiny as if they were data frames, they are actually functions that return data frames (or other objects).
isolate({
print(reactiv...
How to redirect output with subprocess in Python?
...
UPDATE: os.system is discouraged, albeit still available in Python 3.
Use os.system:
os.system(my_cmd)
If you really want to use subprocess, here's the solution (mostly lifted from the documentation for subprocess):
p = subprocess.Popen(my_cmd, shell=True)
os.waitpid(p.pid, 0)
OTOH,...
`new function()` with lower case “f” in JavaScript
...
3 Answers
3
Active
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Using isKindOfClass with Swift
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answered Jun 14 '14 at 13:29
KPMKPM
10k33 gold badges4141 silver badges6363 bronze badges
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What is the difference between assert, expect and should in Chai?
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edited May 23 '17 at 12:10
Community♦
111 silver badge
answered Jan 28 '14 at 12:01
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Rails ActionMailer - format sender and recipient name/email address
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237
If you are taking user input for name and email, then unless you very carefully validate or esc...
How many GCC optimization levels are there?
...n level is specified)
-O1 (optimize minimally)
-O2 (optimize more)
-O3 (optimize even more)
-Ofast (optimize very aggressively to the point of breaking standard compliance)
-Og (Optimize debugging experience. -Og enables optimizations that do not interfere with debugging. It should be t...