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How to import a module given its name as string?
...e importlib.import_module for Python 2 and and Python 3.
You can use exec if you want to as well.
Or using __import__ you can import a list of modules by doing this:
>>> moduleNames = ['sys', 'os', 're', 'unittest']
>>> moduleNames
['sys', 'os', 're', 'unittest']
>>> m...
To find whether a column exists in data frame or not
...and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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How does the main() method work in C?
I know there are two different signatures to write the main method -
9 Answers
9
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Create instance of generic type whose constructor requires a parameter?
If BaseFruit has a constructor that accepts an int weight , can I instantiate a piece of fruit in a generic method like this?
...
How do I get the full path of the current file's directory?
... script being run:
import os
os.path.dirname(os.path.abspath(__file__))
If you mean the current working directory:
import os
os.path.abspath(os.getcwd())
Note that before and after file is two underscores, not just one.
Also note that if you are running interactively or have loaded code from...
How to remove elements from a generic list while iterating over it?
...umerable.Range(1, 10));
for (int i = list.Count - 1; i >= 0; i--)
{
if (list[i] > 5)
list.RemoveAt(i);
}
list.ForEach(i => Console.WriteLine(i));
Alternately, you can use the RemoveAll method with a predicate to test against:
safePendingList.RemoveAll(item => item.Value ==...
MVC 5 Seed Users and Roles
...d override void Seed(SecurityModule.DataContexts.IdentityDb context)
{
if (!context.Roles.Any(r => r.Name == "AppAdmin"))
{
var store = new RoleStore<IdentityRole>(context);
var manager = new RoleManager<IdentityRole>(store);
var role = new IdentityRole...
What is the difference between Xamarin.Form's LayoutOptions, especially Fill and Expand?
...alignment within its space.
Expand defines whether it occupies more space if available.
Theory
The structure LayoutOptions controls two distinct behaviors:
Alignment: How is the view aligned within the parent view?
Start: For vertical alignment the view is moved to the top. For horizontal ali...
How to get distinct values from an array of objects in JavaScript?
...
If this were PHP I'd build an array with the keys and take array_keys at the end, but JS has no such luxury. Instead, try this:
var flags = [], output = [], l = array.length, i;
for( i=0; i<l; i++) {
if( flags[array[i...
annotation to make a private method public only for test classes [duplicate]
...
If you use FindBugs, I've built a plugin that can actually verify for you that @VisibleForTesting methods are not being used outside test classes.
– Johnco
Jul 23 '15 at 14:40
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