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What is the pythonic way to avoid default parameters that are empty lists?
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print(working_list)
The docs say you should use None as the default and explicitly test for it in the body of the function.
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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)...
Rails 4: List of available datatypes
...t, 2016-Sep-19:
There's a lot more postgres specific datatypes in Rails 4 and even more in Rails 5.
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HTML-encoding lost when attribute read from input field
I’m using JavaScript to pull a value out from a hidden field and display it in a textbox. The value in the hidden field is encoded.
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Get difference between 2 dates in JavaScript? [duplicate]
...e in quotes. The rest of the code gets the time difference in milliseconds and then divides to get the number of days. Date expects mm/dd/yyyy format.
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What is the best way to deal with the NSDateFormatter locale “feechur”?
...to self = [self init]; causes the NSDateFormatter initialization to occur, and setLocale is happy again.
Here is the "final" source for the category's .m:
#import "NSDateFormatter+Locale.h"
@implementation NSDateFormatter (Locale)
- (id)initWithSafeLocale {
static NSLocale* en_US_POSIX = nil;
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Android Fragments and animation
...Fragment Transaction.
Within each Fragment Transaction you can specify in and out animations that will be used for show and hide respectively (or both when replace is used).
The following code shows how you would replace a fragment by sliding out one fragment and sliding the other one in it's pla...
Activity restart on rotation Android
In my Android application, when I rotate the device (slide out the keyboard) then my Activity is restarted ( onCreate is called). Now, this is probably how it's supposed to be, but I do a lot of initial setting up in the onCreate method, so I need either:
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搭建高可用mongodb集群（一）——配置mongodb - 大数据 & AI - 清泛网 - 专...
...r
输出日志如下，成功！
[initandlisten] MongoDB starting : pid=18285 port=27017 dbpath=/data/mongodbtest/master master=1
#日志显示主节点参数
[initandlisten] options: { dbpath: “/data/mongodbtest/master”, master: true }
……..
[initandlisten] waiting for connections ...
How to check if a string is a valid hex color representation?
...beginning
# -> a hash
[0-9A-F] -> any integer from 0 to 9 and any letter from A to F
{6} -> the previous group appears exactly 6 times
$ -> match end
i -> ignore case
If you need support for 3-character HEX codes, use the following:
/^#([0-9A-F]{...