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Select Pandas rows based on list index
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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 ...
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?
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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...
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:
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How to return a string value from a Bash function
...nd substitution is far more explicit and modular" would be relevant if the question were about commands; this question is how to return a string, from a bash function! A built in way to do what the OP has asked is available since Bash 4.3 (2014?) - see my answer below.
– zenaan...
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...
Numpy index slice without losing dimension information
I'm using numpy and want to index a row without losing the dimension information.
6 Answers
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After submitting a POST form open a new window showing the result
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var urlAction = 'whatever.php';
var data = {param1:'value1'};
var $form = $('<form target="_blank" method="POST" action="' + urlAction + '">');
$.each(data, function(k,v){
$form.append('<input type="hidden" name="' + k + '" value="' + v ...
mongoDB/mongoose: unique if not null
...s without the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true, unique: true, sparse: true}
Or in the shell:
db.users.ensureIndex({email: 1}, {unique: true, sparse: true});
Note that a unique, sparse index still does not...
How to override and extend basic Django admin templates?
How do I override an admin template (e.g. admin/index.html) while at the same time extending it (see https://docs.djangoproject.com/en/dev/ref/contrib/admin/#overriding-vs-replacing-an-admin-template )?
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