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How do I parallelize a simple Python loop?
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edited Jun 17 '15 at 17:14
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Number of elements in a javascript object
...the number of elements in a javascript object?? (i.e. constant-time complexity).
6 Answers
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Convert a row of a data frame to vector
...ract a single row from a data frame you get a one-row data frame. Convert it to a numeric vector:
as.numeric(df[1,])
As @Roland suggests, unlist(df[1,]) will convert the one-row data frame to a numeric vector without dropping the names. Therefore unname(unlist(df[1,])) is another, slightly m...
How do I execute inserts and updates in an Alembic upgrade script?
...arative (as opposed to class-Mapper-Table or core) to define your models. It should be relatively straightforward to adapt this to the other forms.
Note that Alembic provides some basic data functions: op.bulk_insert() and op.execute(). If the operations are fairly minimal, use those. If the migr...
How do I copy items from list to list without foreach?
How do I transfer the items contained in one List to another in C# without using foreach ?
8 Answers
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How to call a stored procedure from Java and JPA
I am writing a simple web application to call a stored procedure and retrieve some data.
Its a very simple application, which interacts with client's database. We pass employee id and company id and the stored procedure will return employee details.
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How to access component methods from “outside” in ReactJS?
...n’t I access the component methods from “outside” in ReactJS? Why is it not possible and is there any way to solve it?
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How to convert An NSInteger to an int?
...42;
int myInt = (int) myInteger;
NSInteger is nothing more than a 32/64 bit int. (it will use the appropriate size based on what OS/platform you're running)
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How to print a percentage value in python?
...gt; 1 / 3
0.3333333333333333
# The above 33% example would could now be written without the explicit
# float conversion:
>>> print "{0:.0f}%".format(1/3 * 100)
33%
# Or even shorter using the format mini language:
>>> print "{:.0%}".format(1/3)
33%
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How to redirect 404 errors to a page in ExpressJS?
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I found this example quite helpful:
https://github.com/visionmedia/express/blob/master/examples/error-pages/index.js
So it is actually this part:
// "app.router" positions our routes
// above the middleware defined below,
// this means that Expr...