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Numpy how to iterate over columns of array?
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– Ibrahim Muhammad
Sep 23 '13 at 17:08
49
For those wondering, array.T isn't costly, as it just c...
MongoDB副本集详解 优于以往的主从模式 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...g/downloads
实验环境使用的Mongodb版本为mongodb-linux-x86_64-2.6.0
由三台虚拟机搭建，配置为单核,1G内存。实验环境如下:
MongoDB的副本集不同于以往的主从模式。
在集群Master故障的时候，副本集可以自动投票，选举出新的Master，并...
Group by multiple columns in dplyr, using string vector input
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data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>%...
Underscore: sortBy() based on multiple attributes
...dArray = _(patients).chain().sortBy(function(patient) {
return patient[0].name;
}).sortBy(function(patient) {
return patient[0].roomNumber;
}).value();
When the second sortBy finds that John and Lisa have the same room number it will keep them in the order it found them, which the first so...
How to check if BigDecimal variable == 0 in java?
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10 Answers
10
Active
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CGContextDrawImage draws image upside down when passed UIImage.CGImage
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Instead of
CGContextDrawImage(context, CGRectMake(0, 0, 145, 15), image.CGImage);
Use
[image drawInRect:CGRectMake(0, 0, 145, 15)];
In the middle of your begin/end CGcontext methods.
This will draw the image with the correct orientation into your current image context...
Changing font size and direction of axes text in ggplot2
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301
Use theme():
d <- data.frame(x=gl(10, 1, 10, labels=paste("long text label ", letters[1:10]...
How does the algorithm to color the song list in iTunes 11 work? [closed]
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+50
I approximated the iTunes 11 color algorithm in Mathematica given the album cover as input:
How I did it
Through trial and error...
How does this CSS produce a circle?
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How does a border of 180 pixels with height/width-> 0px become a circle with a radius of 180 pixels?
Let's reformulate that into two questions:
Where do width and height actually apply?
Let's have a look at the areas of a typical box (source...
How to base64 encode image in linux bash / shell
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You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the filename itself.
test="$(cat DSC_0251.JPG | base64)"
However, base64 can read from the file itself:
test=$( base64 DSC_0251.JPG )
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