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Get full path of the files in PowerShell
...ach loop, like so:
get-childitem "C:\windows\System32" -recurse | where {$_.extension -eq ".txt"} | % {
Write-Host $_.FullName
}
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When is “i += x” different from “i = i + x” in Python?
...
This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used for modifyi...
NoClassDefFoundError: android.support.v7.internal.view.menu.MenuBuilder
... those conditions and change the app flow:
public static boolean isSamsung_4_2_2() {
String deviceMan = Build.MANUFACTURER;
String deviceRel = Build.VERSION.RELEASE;
return "samsung".equalsIgnoreCase(deviceMan) && deviceRel.startsWith("4.2.2");
}
Then in the activity's onCreat...
How to read the database table name of a Model instance?
...
Found the answer myself: the _meta attribute of an instance has the information:
model_instance._meta.db_table
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Change column type from string to float in Pandas
...
You have four main options for converting types in pandas:
to_numeric() - provides functionality to safely convert non-numeric types (e.g. strings) to a suitable numeric type. (See also to_datetime() and to_timedelta().)
astype() - convert (almost) any type to (almost) any other type ...
Web-scraping JavaScript page with Python
...:
import requests
from bs4 import BeautifulSoup
response = requests.get(my_url)
soup = BeautifulSoup(response.text)
soup.find(id="intro-text")
# Result:
<p id="intro-text">No javascript support</p>
Scraping with JS support:
from selenium import webdriver
driver = webdriver.PhantomJS(...
How to check whether a file or directory exists?
...iven file or directory exists
func exists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil { return true, nil }
if os.IsNotExist(err) { return false, nil }
return false, err
}
Edited to add error handling.
...
Convert Long into Integer
...ong) l;
All three versions generate almost identical byte code:
0 ldc2_w <Long 123> [17]
3 invokestatic java.lang.Long.valueOf(long) : java.lang.Long [19]
6 astore_1 [l]
// first
7 aload_1 [l]
8 invokevirtual java.lang.Long.intValue() : int [25]
11 invokestatic java.lang.Integer...
Add swipe to delete UITableViewCell
... and updating the tableview)
}
}
Swift 3.0:
override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {...
What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...