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How do we control web page caching, across all browsers?
...revalidate
Pragma: no-cache
Expires: 0
The Cache-Control is per the HTTP 1.1 spec for clients and proxies (and implicitly required by some clients next to Expires). The Pragma is per the HTTP 1.0 spec for prehistoric clients. The Expires is per the HTTP 1.0 and 1.1 specs for clients and proxies. I...
Format a number as 2.5K if a thousand or more, otherwise 900
I need to show a currency value in the format of 1K of equal to one thousand, or 1.1K, 1.2K, 1.9K etc, if its not an even thousands, otherwise if under a thousand, display normal 500, 100, 250 etc, using javascript to format the number?
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Moving decimal places over in a double
So I have a double set to equal 1234, I want to move a decimal place over to make it 12.34
9 Answers
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How can I apply a function to every row/column of a matrix in MATLAB?
...an apply a function to every item in a vector by saying, for example, v + 1 , or you can use the function arrayfun . How can I do it for every row/column of a matrix without using a for loop?
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Emulate ggplot2 default color palette
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It is just equally spaced hues around the color wheel, starting from 15:
gg_color_hue <- function(n) {
hues = seq(15, 375, length = n + 1)
hcl(h = hues, l = 65, c = 100)[1:n]
}
For example:
n = 4
cols = gg_color_hue(n)
dev.new(width = 4, height = 4)
plot(1:n, pch = 16, cex = 2, col...
Plot a legend outside of the plotting area in base graphics?
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10 Answers
10
Active
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Convert column classes in data.table
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105
For a single column:
dtnew <- dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘...
App Inventor 2 数学代码块 · App Inventor 2 中文网
...最多的元素 (mode)
案例：指定将二进制的某一位(Bit)改为1
案例：指定将二进制的某一位(Bit)改为0
基础数字块 ( 0 )
进制数字块 ( 0 )
等于 ( = )
不等于 ( ≠ )
大于 ( > )
大于等于 ( ≥ )
小于 ( < )
小于等于 ( ≤ )
加 (...
How to sort an array in descending order in Ruby
... Here's what I found out:
#!/usr/bin/ruby
require 'benchmark'
ary = []
1000.times {
ary << {:bar => rand(1000)}
}
n = 500
Benchmark.bm(20) do |x|
x.report("sort") { n.times { ary.sort{ |a,b| b[:bar] <=> a[:bar] } } }
x.report("sort reverse") { n.times ...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
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216
sqrtss gives a correctly rounded result. rsqrtss gives an approximation to the reciprocal, acc...