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Create an array with random values
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var random_array = new Array(40).fill().map((a, i) => a = i).sort(() => Math.random() - 0.5); I think this does the same as above
– Jamie337nichols
Sep 16 '19 at 18:47
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Is there any particular difference between intval and casting to int - `(int) X`?
... behavior is a little surprising given the fact that the function theoretically can do base conversion. It definitely tripped me up before, but perhaps I just need to RTFM a bit more carefully :)
– t-dub
Feb 10 '12 at 17:07
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Render a variable as HTML in EJS
...de ('newline slurping') with -%> ending tag
Whitespace-trim mode (slurp all whitespace) for control flow with <%_ _%>
Control flow with <% %>
So, in your case it is going to be <%- variable %> where variable is something like
var variable = "text here <br> and some more t...
Waiting until two async blocks are executed before starting another block
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NSLog(@"Block3");
});
// only for non-ARC projects, handled automatically in ARC-enabled projects.
dispatch_release(group);
and could produce output like this:
2012-08-11 16:10:18.049 Dispatch[11858:1e03] Block1
2012-08-11 16:10:18.052 Dispatch[11858:1d03] Block2
2012-08-11 16:10:23.051 Dis...
Stack, Static, and Heap in C++
...t understood very well these three concepts. When do I have to use dynamic allocation (in the heap) and what's its real advantage? What are the problems of static and stack? Could I write an entire application without allocating variables in the heap?
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How do you write a migration to rename an ActiveRecord model and its table in Rails?
...ble_name
end
end
I had to go and rename the model declaration file manually.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rena...
Java URL encoding of query string parameters
... are represented by +, not %20, which is legitimately valid. The %20 is usually to be used to represent spaces in URI itself (the part before the URI-query string separator character ?), not in query string (the part after ?).
Also note that there are three encode() methods. One without Charset as s...
Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
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List all tables in postgresql information_schema
What is the best way to list all of the tables within PostgreSQL's information_schema?
8 Answers
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Change one value based on another value in pandas
...ere.
Assuming you can load your data directly into pandas with pandas.read_csv then the following code might be helpful for you.
import pandas
df = pandas.read_csv("test.csv")
df.loc[df.ID == 103, 'FirstName'] = "Matt"
df.loc[df.ID == 103, 'LastName'] = "Jones"
As mentioned in the comments, you ...