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Python: using a recursive algorithm as a generator
...],string[:i]+string[i+1:] pairs. Then it would be: for letter,rest in first_letter_options(string): for perm in getPermuations(rest): yield letter+perm
– Thomas Andrews
Oct 14 '16 at 19:04
...
How to bind an enum to a combobox control in WPF?
... an optional blank value for default/no selection
[Description("")]
NOT_SET = 0,
[Description("Sunday")]
SUNDAY,
[Description("Monday")]
MONDAY,
...
}
First I created helper class with a couple methods to deal with enums. One method gets a description for a specific value, the other ...
Git cherry pick vs rebase
... /
D---E---F---G master
Cherry-pick:
$ git checkout master -b topic_new
$ git cherry-pick A^..C
You get:
A---B---C topic
/
D---E---F---G master
\
A'--B'--C' topic_new
for more info about git this book has most of it (http://git-scm.com/book)
...
iOS JavaScript bridge
...riptObject
@interface WebScriptBridge: NSObject
- (void)someEvent: (uint64_t)foo :(NSString *)bar;
- (void)testfoo;
+ (BOOL)isKeyExcludedFromWebScript:(const char *)name;
+ (BOOL)isSelectorExcludedFromWebScript:(SEL)aSelector;
+ (WebScriptBridge*)getWebScriptBridge;
@end
static WebScriptBridge *gW...
How to rename a file using Python
...3.7 ubuntu, works for me using relative paths
– toing_toing
Feb 28 '19 at 15:51
2
@toing_toing of...
How to turn off INFO logging in Spark?
...
Inspired by the pyspark/tests.py I did
def quiet_logs(sc):
logger = sc._jvm.org.apache.log4j
logger.LogManager.getLogger("org"). setLevel( logger.Level.ERROR )
logger.LogManager.getLogger("akka").setLevel( logger.Level.ERROR )
Calling this just after creating...
How do I concatenate two lists in Python?
...>>> l1 = [1, 2, 3]
>>> l2 = [4, 5, 6]
>>> joined_list = [*l1, *l2] # unpack both iterables in a list literal
>>> print(joined_list)
[1, 2, 3, 4, 5, 6]
This functionality was defined for Python 3.5 it hasn't been backported to previous versions in the 3.x family...
Getting time elapsed in Objective-C
...er to use Apple's function CACurrentMediaTime!
I also benchmarked the mach_timebase_info call and it takes approximately 19ns on my iPhone 6, so I removed the (not threadsafe) code which was caching the output of that call.
#include <mach/mach.h>
#include <mach/mach_time.h>
uint64_t g...
Pandas aggregate count distinct
...
How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
Create unique constraint with null columns
...
Create two partial indexes:
CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id)
WHERE menu_id IS NOT NULL;
CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id)
WHERE menu_id IS NULL;
This way, there can only be one combination...