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List comprehension vs. lambda + filter
I happened to find myself having a basic filtering need: I have a list and I have to filter it by an attribute of the items.
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How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
17
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Status bar won't disappear
I'm creating an application and I want the status bar hidden. When I test the app, the status bar is hidden whilst the splash screen is shown, but once the app is fully loaded, the status bar reappears.
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How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
Understanding Fragment's setRetainInstance(boolean)
...you leave the Activity by pressing the back button (thus, calling finish() and effectively destroying the Activity), all of the Activitys attached Fragments will also be destroyed.
Why doesn't it work with fragments on the back stack?
There are probably multiple reasons why it's not supported,...
How do I Sort a Multidimensional Array in PHP [duplicate]
...a loaded into a multidimensional array. In this way each "row" is a record and each "column" contains the same type of data. I am using the function below to load my CSV file.
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How do you test private methods with NUnit?
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+1 I've just come up against this issue and in my case there's a "mapping" algorithm that happens in between the private and the public meaning if I were to Unit Test the public, it would actually be an integration test. In this scenario I think it trying to write ...
Using GCC to produce readable assembly?
...source code with disassembly
-l, --line-numbers Include line numbers and filenames in output
objdump -drwC -Mintel is nice:
-r shows symbol names on relocations (so you'd see puts in the call instruction below)
-R shows dynamic-linking relocations / symbol names (useful on shared libraries...
Set up a scheduled job?
I've been working on a web app using Django, and I'm curious if there is a way to schedule a job to run periodically.
24 A...
Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) fro...