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How to detect reliably Mac OS X, iOS, Linux, Windows in C preprocessor? [duplicate]
If there's some cross-platform C/C++ code that should be compiled on Mac OS X, iOS, Linux, Windows, how can I detect them reliably during preprocessor process?
...
SQL query for finding records where count > 1
...p int(11) not null,
dt date not null
);
insert into payment values
(1,123,55555,'2009-12-12'),
(1,123,66666,'2009-12-12'),
(1,123,77777,'2009-12-13'),
(2,456,77777,'2009-12-14'),
(2,456,77777,'2009-12-14'),
(2,789,77777,'2009-12-14'),
(2,789,77777,'2009-12-14');
select foo.user_id, foo.cnt fro...
What is the difference between os.path.basename() and os.path.dirname()?
What is the difference between os.path.basename() and os.path.dirname() ?
2 Answers
...
Retrieving Android API version programmatically
...on, the SDK level (integer) the phone is running is available in:
android.os.Build.VERSION.SDK_INT
The class corresponding to this int is in the android.os.Build.VERSION_CODES class.
Code example:
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP){
// Do some...
Remove duplicated rows using dplyr
...ction for this purpose.
Original answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_nu...
Correct way to write line to file?
...le:
the_file.write('Hello\n')
From The Documentation:
Do not use os.linesep as a line terminator when writing files opened in text mode (the default); use a single '\n' instead, on all platforms.
Some useful reading:
The with statement
open()
'a' is for append, or use
'w' to write wi...
How do I change the working directory in Python?
...
You can change the working directory with:
import os
os.chdir(path)
There are two best practices to follow when using this method:
Catch the exception (WindowsError, OSError) on invalid path. If the exception is thrown, do not perform any recursive operations, especial...
Checking if a string can be converted to float in Python
... ------------
print(isfloat("")) False
print(isfloat("1234567")) True
print(isfloat("NaN")) True nan is also float
print(isfloat("NaNananana BATMAN")) False
print(isfloat("123.456")) True
print(isfloat("123.E4")) ...
Deleting folders in python recursively
...o. As asked, the question was how to delete EMPTY directories.The docs for os.walk give an example that almost exactly matches this question: import os for root, dirs, files in os.walk(top, topdown=False): for name in dirs: os.rmdir(os.path.join(root, name))
...
How do I execute a program from Python? os.system fails due to spaces in path
...
Yes, the os.exec* functions will replace the current process, so your python process won't continue. They're used more on unix where the general method for a shell to launch a command is to fork() and then exec() in the child.
...