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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.
...
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 ...
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...
In mongoDb, how do you remove an array element by its index?
...
There is no straight way of pulling/removing by array index. In fact, this is an open issue http://jira.mongodb.org/browse/SERVER-1014 , you may vote for it.
The workaround is using $unset and then $pull:
db.lists.update({}, {$unset : {"interests.3" : 1 }})
db.lists.update({...
How to index into a dictionary?
...re about the order of the entries and want to access the keys or values by index anyway, you can use d.keys()[i] and d.values()[i] or d.items()[i]. (Note that these methods create a list of all keys, values or items in Python 2.x. So if you need them more then once, store the list in a variable to...
How do I create test and train samples from one dataframe with pandas?
...rac=0.8,random_state=200) #random state is a seed value
test=df.drop(train.index)
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