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Why is a combiner needed for reduce method that converts type in java 8
...ch; int cannot be converted to java.lang.String. Actually, I think passing 0 as the identity value is also wrong here, since a String is expected (T).
Also note that this version of reduce processes a stream of Ts and returns a T, so you can't use it to reduce a stream of String to an int.
The thr...
Convert Unix timestamp to a date string
...
With GNU's date you can do:
date -d "@$TIMESTAMP"
# date -d @0
Wed Dec 31 19:00:00 EST 1969
(From: BASH: Convert Unix Timestamp to a Date)
On OS X, use date -r.
date -r "$TIMESTAMP"
Alternatively, use strftime(). It's not available directly from the shell, but you can access it v...
How to set a default value for a datetime column to record creation time in a migration?
...e is a sample migration:
class CreatePosts < ActiveRecord::Migration[5.0]
def change
create_table :posts do |t|
t.datetime :modified_at, default: -> { 'CURRENT_TIMESTAMP' }
t.timestamps
end
end
end
See discussion at https://github.com/rails/rails/issues/27077 and an...
How do I check CPU and Memory Usage in Java?
...ime.freeMemory();
sb.append("free memory: " + format.format(freeMemory / 1024) + "<br/>");
sb.append("allocated memory: " + format.format(allocatedMemory / 1024) + "<br/>");
sb.append("max memory: " + format.format(maxMemory / 1024) + "<br/>");
sb.append("total free memory: " + fo...
Function for Factorial in Python
...actorial (available in Python 2.6 and above):
import math
math.factorial(1000)
If you want/have to write it yourself, you can use an iterative approach:
def factorial(n):
fact = 1
for num in range(2, n + 1):
fact *= num
return fact
or a recursive approach:
def factorial(n)...
What is Model in ModelAndView from Spring MVC?
...
answered Feb 20 '11 at 5:20
limclimc
35.4k1919 gold badges9292 silver badges139139 bronze badges
...
Convert PDF to clean SVG? [closed]
...
answered Apr 23 '12 at 20:53
Saintt Sheldon PatnettSaintt Sheldon Patnett
1,12388 silver badges88 bronze badges
...
Is there a JavaScript function that can pad a string to get to a determined length?
... solution here and this is for me much much simpler:
var n = 123
String("00000" + n).slice(-5); // returns 00123
("00000" + n).slice(-5); // returns 00123
(" " + n).slice(-5); // returns " 123" (with two spaces)
And here I made an extension to the string object:
String.prototype.paddingLef...
Find the day of a week
...
305
df = data.frame(date=c("2012-02-01", "2012-02-01", "2012-02-02"))
df$day <- weekdays(as.Dat...