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Efficient evaluation of a function at every cell of a NumPy array
...t be faster than the "manual" double loop iteration and assignment through all the array elements. Especially, because it stores the result to a newly created variable (and not directly to the initial input). Thanks a lot for your reply though:)
– Peter
Oct 9 '...
How to select rows from a DataFrame based on column values?
...have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar one 1 2
3 bar three 3 6
6 foo one 6 12
7 foo three 7 14
Note,...
How would I run an async Task method synchronously?
I'm learning about async/await, and ran into a situation where I need to call an async method synchronously. How can I do that?
...
Is there a command to refresh environment variables from the command prompt in Windows?
... environment variables with a vbs script, but you need a bat script to actually change the current environment variables, so this is a combined solution.
Create a file named resetvars.vbs containing this code, and save it on the path:
Set oShell = WScript.CreateObject("WScript.Shell")
filename =...
Error Dropping Database (Can't rmdir '.test\', errno: 17)
Basically, I was taught on how to create a root password using the "mysqladmin -u root -p password" command, this was done all through the windows command editor. Now, the next process was to display the default databases (info. schema, mysql and test) which was achieved by using "SHOW DATABASES;"
...
Any way to properly pretty-print ordered dictionaries?
...well if you don't care about the order of the keys. Personally, I wish the __repr__ for OrderedDict would produce output like this but preserve the order of the keys.
– ws_e_c421
Sep 24 '15 at 15:54
...
How do you create nested dict in Python?
...he following:
d = {} # can use defaultdict(dict) instead
for row in file_map:
# derive row key from something
# when using defaultdict, we can skip the next step creating a dictionary on row_key
d[row_key] = {}
for idx, col in enumerate(row):
d[row_key][idx] = col
Ac...
iOS UIImagePickerController result image orientation after upload
...uite similar to this one) that includes a lengthy discussion of what's actually going on.
– Gallymon
Nov 29 '13 at 4:30
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show 21 more comme...
C++中判断文件、目录是否存在的几种方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
if(fh == NULL)
{
printf("%s","can not open the file");
}
三、_access
当然C中还有一种方式是直接调用c的函数库。
就是函数 int _access(const char* path,int mode);
这个函数的功能十分强大。
可以看看msdn的详细介绍
#include <io.h>
#include ...
Getting the name of a child class in the parent class (static context)
...ot possible. in php4 you could implement a terrible hack (examine the debug_backtrace()) but that method does not work in PHP5. references:
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edit: an example of late static binding in PHP 5.3 (mentioned in comments). note there are potential problems in it's current implementat...