大约有 5,000 项符合查询结果（耗时：0.0149秒） [XML]
Python Pandas: Get index of rows which column matches certain value
...
Your suggestion indices = np.flatnonzero(df[col_name] == category_name) gets me exactly what the title of the question asks for, which is surprisingly difficult to find on the Internet.
– ClimbsRocks
Apr 14 '17 at 18:14
...
How to save a PNG image server-side, from a base64 data string
...rings that this tool generates, into actual PNG files on the server, using PHP.
15 Answers
...
LINQ: Distinct values
... id = (int) element.Attribute("id"),
category = (int) element.Attribute("cat") })
.Distinct();
If you're trying to get a distinct set of values of a "larger" type, but only looking at some subset of properties for the distinctness aspect, you pr...
What does $$ (dollar dollar or double dollar) mean in PHP?
...
It's a variable's variable.
<?php
$a = 'hello';
$$a = 'world'; // now makes $hello a variable that holds 'world'
echo "$a ${$a}"; // "hello world"
echo "$a $hello"; // "hello world"
?>
...
Convert DateTime to String PHP
I have already researched a lot of site on how can I convert PHP DateTime object to String. I always see "String to DateTime" and not "DateTime to String"
...
Best way to clear a PHP array's values
...o I wrote it that way because of the authors question "Best way to clear a PHP array's values". It sais 'clear', not 'new instance'. Using unset will clear $foo from the symbol table. I we are talking about very large tables I'd probably recommend $foo = null; unset($foo); since that also would clea...
How to import load a .sql or .csv file into SQLite?
...
Try doing it from the command like:
cat dump.sql | sqlite3 database.db
This will obviously only work with SQL statements in dump.sql. I'm not sure how to import a CSV.
share
...
Are “elseif” and “else if” completely synonymous?
...
From the PHP manual:
In PHP, you can also write 'else if' (in two words) and the behavior would be identical to the one of 'elseif' (in a single word). The syntactic meaning is slightly different (if you're familiar with C, this i...
How do I remove  from the beginning of a file?
...S file that looks fine when I open it using gedit , but when it's read by PHP (to merge all the CSS files into one), this CSS has the following characters prepended to it: 
...
How do I select a merge strategy for a git rebase?
...es are there; they just have to decide exactly how they're going to communicate from rebase to merge.
– Cascabel
Jun 24 '10 at 16:06
...