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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...
Debugging App When Launched by Push Notification
... currently developing an app that receives Push Notifications. I have this all working 100% through a PHP page. There are several different types of push notifications my app can receive. The PHP handles this and sends different packets of information to my app which are all received just fine.
...
How to calculate the sentence similarity using word2vec model of gensim with python
...similarity between vectors:
import numpy as np
from scipy import spatial
index2word_set = set(model.wv.index2word)
def avg_feature_vector(sentence, model, num_features, index2word_set):
words = sentence.split()
feature_vec = np.zeros((num_features, ), dtype='float32')
n_words = 0
...
Is there a way to instantiate objects from a string holding their class name?
...ble: http://www.boost.org/doc/libs/1_54_0/libs/functional/factory/doc/html/index.html
My preference though is to generate wrapper classes which hide the mapping and object creation mechanism. The common scenario I encounter is the need to map different derived classes of some base class to keys, wh...
Creating range in JavaScript - strange syntax
...arr);
Number(i, arr);
Which returns the transformation of i, the current index, to a number.
In conclusion,
The expression
Array.apply(null, { length: 5 }).map(Number.call, Number);
Works in two parts:
var arr = Array.apply(null, { length: 5 }); //1
arr.map(Number.call, Number); //2
The fi...
Issue with adding common code as git submodule: “already exists in the index”
...t error means that projectfolder is already staged ("already exists in the index"). To find out what's going on here, try to list everything in the index under that folder with:
git ls-files --stage projectfolder
The first column of that output will tell you what type of object is in the index a...
LEFT JOIN only first row
...t item, like so...
LEFT JOIN Person ON Person.id = (
SELECT SUBSTRING_INDEX(
GROUP_CONCAT(FirstName ORDER BY FirstName DESC SEPARATOR "_" ), '_', 1)
) FROM Person
);
Since we have DESC as our ORDER BY option, this will return a Person id for someone like "Zack". If we wanted some...
How do you use the ? : (conditional) operator in JavaScript?
...
This is a one-line shorthand for an if-else statement. It's called the conditional operator.1
Here is an example of code that could be shortened with the conditional operator:
var userType;
if (userIsYoungerThan18) {
userType = "Minor";
} else {
userType = "Adult";
}
if (userIsY...
How can I get the corresponding table header (th) from a table cell (td)?
... $th = $td.closest('tbody').prev('thead').find('> tr > th:eq(' + $td.index() + ')');
Or a little bit simplified
var $th = $td.closest('table').find('th').eq($td.index());
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putting datepicker() on dynamically created elements - JQuery/JQueryUI
...n (repeaterWrapper) {
_.each(repeaterWrapper, function (repeaterItem, index) {
var jq_nodes = $(repeaterItem.addedNodes);
jq_nodes.each(function () {
// Date Picker
$(this).parents('.current-repeateritem-container').find('.element-datepicker').datepick...