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Getting a list of all subdirectories in the current directory
...differences between os.walk and os.listdir+os.path.isdir solutions: I just tested on a directory with 10,000 subdirectories (with millions of files in the hierarchy below) and the performance differences are negligible. os.walk: "10 loops, best of 3: 44.6 msec per loop" and os.listdir+os.path.isdir:...
Measuring code execution time
...want to know how much time a procedure/function/order takes to finish, for testing purposes.
7 Answers
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Rails layouts per action?
...trollers in many levels. I have used method before, but wasn't thinking of testing that when I had the problem now, thanks again.
– 244an
Oct 1 '15 at 15:07
...
Try-finally block prevents StackOverflowError
... @assylias: if there's not enough space, you will return from the latest foo() invocation, and invoke foo() in the finally block of your current foo() invocation.
– ninjalj
Sep 15 '12 at 16:10
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When does static class initialization happen?
...extual order as defined in the class.
Consider the example:
public class Test {
static String sayHello() {
return a;
}
static String b = sayHello(); // a static method is called to assign value to b.
// but its a has not been initialized yet.
...
Large-scale design in Haskell? [closed]
...Int, Address)
Good data structures (like zippers) can make some classes of testing needless, as they rule out e.g. out of bounds errors statically.
The profiler
Provide objective evidence of your program's heap and time profiles.
Heap profiling, in particular, is the best way to ensure no unnece...
Avoid trailing zeroes in printf()
...ld widths, then format the number using a format string based on that. The test harness main() shows this in action:
40.00000000000000000000 -> 40.000
359.01335000000000263753 -> 359.013
-359.00999000000001615263 -> -359.010
359.00999999999999090505 -> 359.010
3.01357000000000008...
How do you check whether a number is divisible by another number (Python)?
I need to test whether each number from 1 to 1000 is a multiple of 3 or a multiple of 5. The way I thought I'd do this would be to divide the number by 3, and if the result is an integer then it would be a multiple of 3. Same with 5.
...
What is the difference between a map and a dictionary?
...lements that can support the insertion and deletion of elements as well as test for membership
For example, we have a set of elements { A, B, C, D... } that we've been able to insert and could start deleting, and we're able to query "is C present?".
The Computing Science notion of map though is b...
How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
...
Note this is not standard SQL. An example from the manual:
CREATE TABLE test (
id INT UNSIGNED NOT NULL AUTO_INCREMENT,
data VARCHAR(64) DEFAULT NULL,
ts TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (id)
);
mysql> REPLACE INTO test VALUES (1, '...