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Loop through list with both content and index [duplicate]
... for me to loop through a python list to get both the contents and their indexes. What I usually do is the following:
6 A...
Add a reference column migration in Rails 4
...t; ActiveRecord::Migration
def change
add_reference :uploads, :user, index: true
end
end
Then, run the migration using rake db:migrate.
This migration will take care of adding a new column named user_id to uploads table (referencing id column in users table), PLUS it will also add an index...
In an array of objects, fastest way to find the index of an object whose attributes match a search
...field' attribute:
var elementPos = array.map(function(x) {return x.id; }).indexOf(idYourAreLookingFor);
var objectFound = array[elementPos];
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Is it possible to make an ASP.NET MVC route based on a subdomain?
...)
{
var url = httpContext.Request.Headers["HOST"];
var index = url.IndexOf(".");
if (index < 0)
return null;
var subDomain = url.Substring(0, index);
if (subDomain == "user1")
{
var routeData = new RouteData(this, new ...
What is the most efficient way to loop through dataframes with pandas? [duplicate]
...s of pandas now include a built-in function for iterating over rows.
for index, row in df.iterrows():
# do some logic here
Or, if you want it faster use itertuples()
But, unutbu's suggestion to use numpy functions to avoid iterating over rows will produce the fastest code.
...
Filtering Pandas DataFrames on dates
...
If date column is the index, then use .loc for label based indexing or .iloc for positional indexing.
For example:
df.loc['2014-01-01':'2014-02-01']
See details here http://pandas.pydata.org/pandas-docs/stable/dsintro.html#indexing-selection
...
How to loop through array in jQuery?
...upported in any version of IE.
jQuery.each:
jQuery.each(substr, function(index, item) {
// do something with `item` (or `this` is also `item` if you like)
});
(Link to docs)
Advantages: All of the same advantages as forEach, plus you know it's there since you're using jQuery.
Disadvantages...
git update-index --assume-unchanged on directory
...
git update-index wants the file names on its command line, not on its standard input.
Step 1:
cd into the folder you want to assume is unchanged
Step 2:
You can do either this:
git update-index --assume-unchanged $(git ls-files | ...
Add one row to pandas DataFrame
...
You can use df.loc[i], where the row with index i will be what you specify it to be in the dataframe.
>>> import pandas as pd
>>> from numpy.random import randint
>>> df = pd.DataFrame(columns=['lib', 'qty1', 'qty2'])
>>> for i i...
Get loop counter/index using for…of syntax in JavaScript
... them, there’s ES5’s forEach method that passes both the value and the index to the function you give it:
var myArray = [123, 15, 187, 32];
myArray.forEach(function (value, i) {
console.log('%d: %s', i, value);
});
// Outputs:
// 0: 123
// 1: 15
// 2: 187
// 3: 32
Or ES6’s Array.proto...