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How to check if hex color is “too black”?
...rceived brightness.
Assuming a six character colour:
var c = c.substring(1); // strip #
var rgb = parseInt(c, 16); // convert rrggbb to decimal
var r = (rgb >> 16) & 0xff; // extract red
var g = (rgb >> 8) & 0xff; // extract green
var b = (rgb >> 0) & 0xff;...
What is SYSNAME data type in SQL Server?
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150
sysname is a built in datatype limited to 128 Unicode characters that, IIRC, is used primarily...
Convert JavaScript string in dot notation into an object reference
...However, if that's not the case, consider if any of these apply:
case 1: As the primary method of working with your data (e.g. as your app's default form of passing objects around and dereferencing them). Like asking "how can I look up a function or variable name from a string".
This is...
Add single element to array in numpy
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167
append() creates a new array which can be the old array with the appended element.
I think it...
Pandas dataframe get first row of each group
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>>> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 seco...
Modular multiplicative inverse function in Python
...e inverse of a number, i.e. a number y = invmod(x, p) such that x*y == 1 (mod p) ? Google doesn't seem to give any good hints on this.
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MySQL foreign key constraints, cascade delete
...-----+
| id | name | | id | name |
+----+------+ +----+---------+
| 1 | red | | 1 | mittens |
| 2 | blue | | 2 | boots |
+---++------+ +----+---------+
products_categories:
+------------+-------------+
| product_id | category_id |
+------------+-------------+
| 1 | 1 ...
Python integer division yields float
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answered Aug 15 '09 at 21:51
Brandon E TaylorBrandon E Taylor
23.1k66 gold badges4343 silver badges6868 bronze badges
...
What is a non-capturing group in regular expressions?
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