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round() for float in C++
...offers a simple set of rounding functions.
#include <boost/math/special_functions/round.hpp>
double a = boost::math::round(1.5); // Yields 2.0
int b = boost::math::iround(1.5); // Yields 2 as an integer
For more information, see the Boost documentation.
Edit: Since C++11, there are std::r...
How do you debug PHP scripts? [closed]
...step into the code is a much better way to debug then the old method of var_dump and print at various points to see where your flow goes wrong. When all else fails though and all I have is SSH and vim I still var_dump()/die() to find where the code goes south.
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Alternatives to gprof [closed]
... in this way:
g++ -m64 -fno-omit-frame-pointer -g main.cpp -L. -ltcmalloc_minimal -o my_test
I use libmalloc_minimial.so since it is compiled with -fno-omit-frame-pointer while libc malloc seems to be compiled without this option.
Then I run my test program
./my_test 100000000
Then I record ...
How do I wait for an asynchronously dispatched block to finish?
...synchronous request"];
NSURL *url = [NSURL URLWithString:@"http://www.apple.com"];
NSURLSessionTask *task = [self.session dataTaskWithURL:url completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
XCTAssertNil(error, @"dataTaskWithURL error %@", error);
...
How to plot two columns of a pandas data frame using points?
...specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(10)}
df = pd.DataFrame(d)
df....
What is the best method to merge two PHP objects?
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If your objects only contain fields (no methods), this works:
$obj_merged = (object) array_merge((array) $obj1, (array) $obj2);
This actually also works when objects have methods. (tested with PHP 5.3 and 5.6)
sha...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
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Or set column as unique from the SQL Query window:
alter table location_key drop constraint pinky;
alter table your_table add constraint pinky unique(yourcolumn);
Changes take effect immediately:
Command(s) completed successfully.
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Find the nth occurrence of substring in a string
... more Pythonic version of the straightforward iterative solution:
def find_nth(haystack, needle, n):
start = haystack.find(needle)
while start >= 0 and n > 1:
start = haystack.find(needle, start+len(needle))
n -= 1
return start
Example:
>>> find_nth("fo...
Tracking the script execution time in PHP
...amount of CPU time a particular script has used in order to enforce the max_execution_time limit.
18 Answers
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ADB Shell Input Events
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By adb shell input keyevent, either an event_code or a string will be sent to the device.
usage: input [text|keyevent]
input text <string>
input keyevent <event_code>
Some possible values for event_code are:
0 --> "KEYCODE_UNKNOWN"
1 --> "K...