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Best way to handle list.index(might-not-exist) in python?
...except clause. This is the pythonic way. ValueError will be raised by the .index method only, because it's the only code you have there!
To answer the comment:
In Python, easier to ask forgiveness than to get permission philosophy is well established, and no index will not raise this type of error ...
How to insert element into arrays at specific position?
...Also, using array_merge as TMS suggested won't require you to use a unique index. EXAMPLE: Add "new-value" to an existing array: $b = array_merge( array_slice( $a, 0, 1, true ), array( 'new-value' ), array_slice( $a, 1, null, true ) );
– Radley Sustaire
Jun 20 ...
What are the best practices for using a GUID as a primary key, specifically regarding performance?
...ario.
the clustering key (the column or columns that define the "clustered index" on the table) - this is a physical storage-related thing, and here, a small, stable, ever-increasing data type is your best pick - INT or BIGINT as your default option.
By default, the primary key on a SQL Server ta...
How to get a index value from foreach loop in jstl
...
use varStatus to get the index c:forEach varStatus properties
<c:forEach var="categoryName" items="${categoriesList}" varStatus="loop">
<li><a onclick="getCategoryIndex(${loop.index})" href="#">${categoryName}</a></l...
How to remove specific elements in a numpy array
...returns a new array with sub-arrays along an axis deleted
numpy.delete(a, index)
For your specific question:
import numpy as np
a = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
index = [2, 3, 6]
new_a = np.delete(a, index)
print(new_a) #Prints `[1, 2, 5, 6, 8, 9]`
Note that numpy.delete() returns ...
How do I get the row count of a pandas DataFrame?
...
You can use the .shape property or just len(DataFrame.index). However, there are notable performance differences ( len(DataFrame.index) is fastest).
Code to reproduce the plot:
import numpy as np
import pandas as pd
import perfplot
perfplot.save(
"out.png",
setup=lam...
How can I use the $index inside a ng-repeat to enable a class and show a DIV?
...sue here is that ng-repeat creates its own scope, so when you do selected=$index it creates a new a selected property in that scope rather than altering the existing one. To fix this you have two options:
Change the selected property to a non-primitive (ie object or array, which makes javascript lo...
Select Pandas rows based on list index
...
List = [1, 3]
df.ix[List]
should do the trick!
When I index with data frames I always use the .ix() method. Its so much easier and more flexible...
UPDATE
This is no longer the accepted method for indexing. The ix method is deprecated. Use .iloc for integer based indexing and ...
Getting a list item by index
...g c# moving over from Java. I can't seem to find how to get a list item by index. In java to get the first item of the list it would be:
...
Callback after all asynchronous forEach callbacks are completed
...sole.log('all done'); }
var itemsProcessed = 0;
[1, 2, 3].forEach((item, index, array) => {
asyncFunction(item, () => {
itemsProcessed++;
if(itemsProcessed === array.length) {
callback();
}
});
});
(thanks to @vanuan and others) This approach guarantees that all items...