大约有 3,516 项符合查询结果（耗时：0.0145秒） [XML]
Return multiple columns from pandas apply()
...bellow, I got 4x faster.
import pandas as pd
dat = [ [i, 10*i] for i in range(1000)]
df = pd.DataFrame(dat, columns = ["a","b"])
def add_and_sub(row):
add = row["a"] + row["b"]
sub = row["a"] - row["b"]
return add, sub
df[["add", "sub"]] = df.apply(add_and_sub, axis=1, result_type=...
Erasing elements from a vector
...ing of the vector and returns the iterator to the first element after that range. Then erase removes these elements (whose value is unspecified).
share
|
improve this answer
|
...
Explain Morris inorder tree traversal without using stacks or recursion
... will visually display random binary trees
import binarytree as b
for _ in range(10):
print()
print("Example #",_)
tree=b.tree()
print(tree)
MorrisTraversal(tree)
share
|
improv...
Why is enum class preferred over plain enum?
...
Specifying the underlying type if a field have an expression out of the range of this type the compiler will complain instead of changing the underlying type.
I think that this is a good safety improvement.
So Why is enum class preferred over plain enum?, if we can choose the underlying type fo...
How to use double or single brackets, parentheses, curly braces
...construct
Array[1]=element1 Array initialization
[a-z] Range of characters within a Regular Expression
$[ expression ] A non-standard & obsolete version of $(( expression )) [1]
[1] http://wiki.bash-hackers.org/scripting/obsolete
Curly Braces
${variable} ...
techniques for obscuring sensitive strings in C++
... you could for instance make sure that the key is not within the printable range.
Obscuring key with XOR
For instance, you could use XOR to split the key into two byte arrays:
key = key1 XOR key2
If you create key1 with the same byte-length as key you can use (completely) random byte values and...
How to convert a data frame column to numeric type?
...
Something that has helped me: if you have ranges of variables to convert (or just more then one), you can use sapply.
A bit nonsensical but just for example:
data(cars)
cars[, 1:2] <- sapply(cars[, 1:2], as.factor)
Say columns 3, 6-15 and 37 of you dataframe n...
Transactions in .net
...0, the TransactionScope object (System.Transactions.dll) allows use over a range of operations (suitable providers will automatically enlist in the ambient transaction). This makes it easy to retro-fit into existing (non-transactional) code, and to talk to multiple providers (although DTC will get i...
Circle-Rectangle collision detection (intersection)
...er direction) that an intersection is guaranteed. This corresponds to the orange and grey sections in the image. Note that this step must be done after step 2 for the logic to make sense.
The remaining lines calculate the difficult case where the circle may intersect the corner of the rectangle. To ...
Determine distance from the top of a div to top of window with javascript
... variable to see if it's value is 120 but I would recommend checking for a range instead of an exact number. If for instance you scroll with a mouse-wheel, you might very well skip over 120. So if you are trying to apply some CSS or something when the element is within 120px of the top-fold, then ma...