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Best practice for Python assert
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To be able to automatically throw an error when x become less than zero throughout the function. You can use class descriptors. Here is an example:
class LessThanZeroException(Exception):
pass
class variable(object):
def __init__(self, va...
What is the entry point of swift code execution?
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The entry point in a plain Swift module is the file in the module called main.swift. main.swift is the only file which is allowed to have expressions and statements at the top level (all other Swift files in the module can only contain declarations).
Cocoa Touch uses the @UIApplicationMain ...
How can a LEFT OUTER JOIN return more records than exist in the left table?
I have a very basic LEFT OUTER JOIN to return all results from the left table and some additional information from a much bigger table. The left table contains 4935 records yet when I LEFT OUTER JOIN it to an additional table the record count is significantly larger.
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
27.4k66 gold badges6060 silver badges6060 bronze badges
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iOS: Compare two dates
...nclution that the best way of doing it is like this:
- (BOOL)isEndDateIsSmallerThanCurrent:(NSDate *)checkEndDate
{
NSDate* enddate = checkEndDate;
NSDate* currentdate = [NSDate date];
NSTimeInterval distanceBetweenDates = [enddate timeIntervalSinceDate:currentdate];
double secondsI...
Erlang's 99.9999999% (nine nines) reliability
...ntime, the author can state "nine nines reliability" for AXD301 (which was all he ever said, avoiding specifics). It doesn't necessarily mean Erlang is the only cause of such high reliability.
EDIT: In fact, "20 years" itself seems like a misinterpretation. Joe mentions a figure of 20 years in the s...
How do I associate file types with an iPhone application?
...t -application:didFinishLaunchingWithOptions: in the app delegate is only called if your app was not backgrounded when it's opened to handle a file.
– memmons
Oct 10 '11 at 18:32
3...
Extract public/private key from PKCS12 file for later use in SSH-PK-Authentication
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This is possible with a bit of format conversion.
To extract the private key in a format openssh can use:
openssl pkcs12 -in pkcs12.pfx -nocerts -nodes | openssl rsa > id_rsa
To convert the private key to a public key:
openssl...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
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int may be as small as 16 bits on some platforms. It may not be sufficient for your application.
uint32_t is not guaranteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactl...
Truncating all tables in a Postgres database
I regularly need to delete all the data from my PostgreSQL database before a rebuild. How would I do this directly in SQL?
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