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Jinja2 shorthand conditional
... If you need to use a variable, you can use inside {% %} too. Like {% set your_var = 'Update' if files else 'Continue' %}
– jhpg
Jun 25 '17 at 20:43
1
...
What do people find difficult about C pointers? [closed]
...nd then dereferencing the thing uses a very similar notation:
*ip = 4; //sets the value of the thing pointed to by ip to '4'
x = ip; //hey, that's not '4'!
x = *ip; //ahh... there's that '4'
Except when you actually need to get a pointer... then you use an ampersand!
int *ip = &x;
Hoor...
Can PostgreSQL index array columns?
...o enforce index usage because we have only 2 records for this test...
SET enable_seqscan TO off;
EXPLAIN ANALYZE
SELECT * FROM "Test" WHERE "Column1" @> ARRAY[20];
Result:
Bitmap Heap Scan on "Test" (cost=4.26..8.27 rows=1 width=32) (actual time=0.014..0.015 rows=2 loops=1)
Re...
How to split a delimited string into an array in awk?
...orking for me'. especially with colons between the echoed values and split set up to split on '|'??? Typo? Good luck to all.
– shellter
Nov 4 '11 at 23:17
...
Dynamically select data frame columns using $ and a character value
...m to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...
Using the data.table package, which is fast (useful for larger datasets)
https://github.com/Rdatatable/data.table/wiki
library(data.table)
df2 <- setDT(df1)[, lapply(.SD, sum), by=.(year, month), .SDcols=c("x1","x2")]
setDF(df2) # convert back to dataframe
Using the plyr package
req...
React.js: Wrapping one component into another
...xample:
const Counter = () => (
<State initial={0}>
{(val, set) => (
<div onClick={() => set(val + 1)}>
clicked {val} times
</div>
)}
</State>
);
You can get even more fancy and even provide an object
<Promise promise={somePr...
Create empty queryset by default in django form fields
...
You can have an empty queryset by doing this:
MyModel.objects.none()
Although i don't know how are you going to use that form, you can put that as your field's queryset in order to get what you need...
You can find more information here
...
How does Angular $q.when work?
...pass a value to it - but what if I passing object?
– SET
Jun 13 '13 at 12:31
11
value, object, ar...
Configuring diff tool with .gitconfig
... What do you mean by a pre-configured "out-of-the-box" difftool? To set-up an external diff tool "winMerge" which is not in your list I had to do the very same setting which you have mentioned in your post and everything started to work without any additional configuration. So does that mean ...