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How to create a date object from string in javascript [duplicate]
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var d = new Date(2011,10,30);
as months are indexed from 0 in js.
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Using an RDBMS as event sourcing storage
...ifically with SQL, we found that performance really became a bottleneck if indexes and partitions weren't adequately used. Remember events will needs to be streamed in reverse order if you are using snapshots. We tried a few different indexes and found that in practise, some additional indexes were ...
How to extract the decision rules from scikit-learn decision-tree?
...ent, np.argmax(tree_.value[node][0])) for the function to return the class index.
– soupault
Oct 19 '17 at 9:56
2
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Center Align on a Absolutely Positioned Div
...idth, as follows:
div#thing {
position: absolute;
top: 0px;
z-index: 2;
width:400px;
margin-left:-200px;
left:50%;
}
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SQLite: How do I save the result of a query as a CSV file?
...')
df = pd.read_sql('SELECT * from orders', conn)
df.to_csv('orders.csv', index = False)
You can customize the query to only export part of the sqlite table to the CSV file.
You can also run a single command to export all sqlite tables to CSV files:
for table in c.execute("SELECT name FROM sqlite_...
Get unique values from a list in python [duplicate]
...ch, 2019
And a 3rd solution, which is a neat one, but kind of slow since .index is O(n).
mylist = [u'nowplaying', u'PBS', u'PBS', u'nowplaying', u'job', u'debate', u'thenandnow']
unique = [x for i, x in enumerate(mylist) if i == mylist.index(x)]
UPDATE - Oct, 2016
Another solution with reduce, ...
Performance surprise with “as” and nullable types
...mpatible with the memory layout of Nullable<int>. A conversion is required and the code is tricky due to possible boxed enum types. The JIT compiler generates a call to a CLR helper function named JIT_Unbox_Nullable to get the job done. This is a general purpose function for any value type,...
How to add a primary key to a MySQL table?
... goods to goods_old;
create new table with primary key and all necessary indexes:
create table goods (
id int(10) unsigned not null AUTO_INCREMENT
... other columns ...
primary key (id)
);
move all data from the old table into new, disabling keys and indexes to speed up copying:
-...
How to randomly pick an element from an array
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You can use the Random generator to generate a random index and return the element at that index:
//initialization
Random generator = new Random();
int randomIndex = generator.nextInt(myArray.length);
return myArray[randomIndex];
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Table with fixed header and fixed column on pure css
...first column stick to the left, use:
thead th:first-child {
left: 0;
z-index: 1;
}
/* Use overflow:scroll on your container to enable scrolling: */
div {
max-width: 400px;
max-height: 150px;
overflow: scroll;
}
/* Use position: sticky to have it stick to the edge
* and top, right,...