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Create an empty data.frame
...aracter(),
stringsAsFactors=FALSE)
Here's an other example with different column types :
df <- data.frame(Doubles=double(),
Ints=integer(),
Factors=factor(),
Logicals=logical(),
Characters=character(),
...
Applying a function to every row of a table using dplyr?
...swer to this problem becomes:
iris %>%
rowwise() %>%
mutate(Max.Len= max(Sepal.Length,Petal.Length))
Non rowwise alternative
Five years (!) later this answer still gets a lot of traffic. Since it was given, rowwise is increasingly not recommended, although lots of people seem to find...
how to concatenate two dictionaries to create a new one in Python? [duplicate]
...s() + d3.items())'
100000 loops, best of 3: 4.93 usec per loop
Fastest: exploit the dict constructor to the hilt, then one update:
$ python -mtimeit -s'd1={1:2,3:4}; d2={5:6,7:9}; d3={10:8,13:22}' \
'd4 = dict(d1, **d2); d4.update(d3)'
1000000 loops, best of 3: 1.88 usec per loop
Middling: a lo...
AngularJs event to call after content is loaded
...d several nested directives that will generate HTML/Content based on complex loops and conditions. Rendering continues for some time, even after $viewContentLoaded event is triggered. How you can ensure that all elements have been fully rendered then execute certain code? Any feedback?
...
Should I use a data.frame or a matrix?
When should one use a data.frame , and when is it better to use a matrix ?
6 Answers
...
How can I get the corresponding table header (th) from a table cell (td)?
... = $td.closest('tbody').prev('thead').find('> tr > th:eq(' + $td.index() + ')');
Or a little bit simplified
var $th = $td.closest('table').find('th').eq($td.index());
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Running Composer returns: “Could not open input file: composer.phar”
... symfony2 and reading symblog . In third chapter while trying with data-fixtures I tried the command:
36 Answers
...
Why can't yield return appear inside a try block with a catch?
...ion is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant.
There are a few things like this that I've already encountered:
Attributes not being able to be generic
Inability for X to derive from X.Y (a nested class in X)
Iterator bloc...
Unix command to find lines common in two files
I'm sure I once found a unix command which could print the common lines from two or more files, does anyone know its name? It was much simpler than diff .
...
custom listview adapter getView method being called multiple times, and in no coherent order
...
The behavior between 2.3 and 4.x era ListView has changed significantly. The take away is, as ListView is designed, your cells/list_items need to be pure views and they need to be optimized for drawing quickly. According to the Google I/O talk on ListView,...