大约有 40,000 项符合查询结果（耗时：0.0605秒） [XML]
Converting strings to floats in a DataFrame
...newer version of pandas (0.17 and up), you can use to_numeric function. It allows you to convert the whole dataframe or just individual columns. It also gives you an ability to select how to treat stuff that can't be converted to numeric values:
import pandas as pd
s = pd.Series(['1.0', '2', -3])
p...
Why does sudo change the PATH?
...
Yeah, but it's totally counterintuitive. It probably fools the good guys more than the bad guys.
– Brian Armstrong
Jun 20 '09 at 2:24
...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
...
I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
Delete all tags from a Git repository
I want to delete all the tags from a Git repository. How can I do that?
11 Answers
11
...
Random number generation in C++11: how to generate, how does it work? [closed]
...ad about it (what is that engine , maths term like distribution , "where all integers produced are equally likely ").
2...
How to initialize a vector in C++ [duplicate]
...p;arr[0]+N; }
And then you can do this without having to repeat the size all over:
int vv[] = { 12,43 };
std::vector<int> v(begin(vv), end(vv));
share
|
improve this answer
|
...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
How to abandon a hg merge?
...
Ah that is a good detail to know... actually I'm going to delete my comment claiming leaving off -r . is the same
– Thymine
Mar 1 '16 at 15:56
...
How does one generate a random number in Apple's Swift language?
... introduces new easy-to-use random functions for many data types.
You can call the random() method on numeric types.
let randomInt = Int.random(in: 0..<6)
let randomDouble = Double.random(in: 2.71828...3.14159)
let randomBool = Bool.random()
...
What's the best way to unit test protected & private methods in Ruby?
...e: Never mind the send! thing, it was revoked long ago, send/__send__ can call methods of all visibility - redmine.ruby-lang.org/repositories/revision/1?rev=13824
– dolzenko
May 18 '10 at 5:41
...