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Insert new item in array on any position in PHP
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Now I can add more elements before an INDEX
– Abbas
Apr 16 '18 at 5:41
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Select first row in each GROUP BY group?
...otal can be NULL (won't hurt either way, but you'll want to match existing indexes):
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ORDER BY customer, total DESC NULLS LAST, id;
Major points
DISTINCT ON is a PostgreSQL extension of the standard (where only DISTINCT on the whole SELECT list is defined).
List any number of expressions in the ...
Does PostgreSQL support “accent insensitive” collations?
...eded).
SELECT *
FROM users
WHERE unaccent(name) = unaccent('João');
Index
To use an index for that kind of query, create an index on the expression. However, Postgres only accepts IMMUTABLE functions for indexes. If a function can return a different result for the same input, the index could...
PHP_SELF vs PATH_INFO vs SCRIPT_NAME vs REQUEST_URI
...on in CodeIgniter. CodeIgniter sends all requests to the main controller: index.php . However, I don't like to see index.php in the URI. For example, http://www.example.com/faq/whatever will route to http://www.example.com/index.php/faq/whatever . I need a reliable way for a script to know wha...
Selecting multiple columns in a pandas dataframe
..._ syntax (the []'s).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not ...
How to get the index of an element in an IEnumerable?
...ily iterate over the contents. As such, there isn't really a concept of an index. What you are doing really doesn't make a lot of sense for an IEnumerable. If you need something that supports access by index, put it in an actual list or collection.
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How to get index of object by its property in JavaScript?
...turn -1 when not found so it follows the same construct as Array.prototype.indexOf()
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how to split the ng-repeat data with three columns using bootstrap
...">
<div class="column" ng-repeat="item in row">
{{($parent.$index*row.length)+$index+1}}. {{item}}
</div>
</div>
Order items vertically
1 4
2 5
3 6
Regarding vertical columns (list top to bottom) rather than horizontal (left to right), the exact implementation de...
How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
...: <!-- language: c# --> public static string GetColumnName(int index) // zero-based { const byte BASE = 'Z' - 'A' + 1; string name = String.Empty; do { name = Convert.ToChar('A' + index % BASE) + name; index = index / BASE - 1; } while (index >= 0); return name;...
Creating an empty Pandas DataFrame, then filling it?
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Here's a couple of suggestions:
Use date_range for the index:
import datetime
import pandas as pd
import numpy as np
todays_date = datetime.datetime.now().date()
index = pd.date_range(todays_date-datetime.timedelta(10), periods=10, freq='D')
columns = ['A','B', 'C']
Note: we...