大约有 47,000 项符合查询结果（耗时：0.0518秒） [XML]
Group by multiple columns in dplyr, using string vector input
...
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 %>%...
what is faster: in_array or isset? [closed]
...t-in function.
These can be demonstrated by using an array with values (10,000 in the test below), forcing in_array to do more searching.
isset: 0.009623
in_array: 1.738441
This builds on Jason's benchmark by filling in some random values and occasionally finding a value that exists in the a...
Drawable image on a canvas
...|
edited Dec 15 '18 at 12:07
answered Apr 8 '14 at 8:36
Gá...
Numpy how to iterate over columns of array?
...
– Ibrahim Muhammad
Sep 23 '13 at 17:08
49
For those wondering, array.T isn't costly, as it just c...
How to get 0-padded binary representation of an integer in java?
...
201
I think this is a suboptimal solution, but you could do
String.format("%16s", Integer.toBinary...
Programmatically set left drawable in a TextView
...DrawablesWithIntrinsicBounds(int left, int top, int right, int bottom)
set 0 where you don't want images
Example for Drawable on the left:
TextView textView = (TextView) findViewById(R.id.myTxtView);
textView.setCompoundDrawablesWithIntrinsicBounds(R.drawable.icon, 0, 0, 0);
Alternatively, you can ...
How does this CSS produce a circle?
...
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...
CGContextDrawImage draws image upside down when passed UIImage.CGImage
...
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...
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 base64 encode image in linux bash / shell
...
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 )
...