大约有 42,000 项符合查询结果(耗时:0.0410秒) [XML]
What is the equivalent of MATLAB's repmat in NumPy
...h multiple dimensions and gives a similar result to matlab. (Numpy gives a 3d output array as you would expect - matlab for some reason gives 2d output - but the content is the same).
Matlab:
>> repmat([1;1],[1,1,1])
ans =
1
1
Python:
In [46]: a = np.array([[1],[1]])
In [47]: n...
How to swap keys and values in a hash
... (in essence, by letting you access keys through values):
{a: 1, b: 2, c: 3}.key(1)
=> :a
If you want to keep the inverted hash, then Hash#invert should work for most situations:
{a: 1, b: 2, c: 3}.invert
=> {1=>:a, 2=>:b, 3=>:c}
BUT...
If you have duplicate values, invert will...
Javascript - remove an array item by value [duplicate]
...
223
You'll want to use JavaScript's Array splice method:
var tag_story = [1,3,56,6,8,90],
id_ta...
Bootstrap 3 breakpoints and media queries
On the Bootstrap 3 media queries documentation it says:
10 Answers
10
...
How to Correctly Use Lists in R?
...:
Why do these two expressions not return the same result?
x = list(1, 2, 3, 4); x2 = list(1:4)
A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different ...
HTML5 Canvas Resize (Downscale) Image High Quality?
...e. )
Here's an example of canvas scale vs my pixel perfect scale on a 1/3 scale of a zombat.
Notice that the picture might get scaled in your Browser, and is .jpegized by S.O..
Yet we see that there's much less noise especially in the grass behind the wombat, and the branches on its right. The n...
Read user input inside a loop
...
answered Jul 30 '11 at 13:42
dankdank
1,13411 gold badge77 silver badges22 bronze badges
...
Bootstrap 3 Glyphicons are not working
I downloaded bootstrap 3.0 and can't get the glyphicons to work. I get some kind of "E003" error. Any ideas why this is happening? I tried both locally and online and I still get the same problem.
...
How to update Identity Column in SQL Server?
...n the identity column
INSERT INTO YourTable(IdentityCol, otherCol) VALUES(13,'myValue')
GO
-- Delete the old row of which you have inserted a copy (above) (make sure about FK's)
DELETE FROM YourTable WHERE ID=3
GO
--Now set the idenetity_insert OFF to back to the previous track
SET IDENTITY_INSERT Y...
Pass a data.frame column name to a function
... just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[,column])
}
fun1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function(x, colu...