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Error to run Android Studio
I have installed Android Studio and I followed all steps described here
17 Answers
17...
Count, size, length…too many choices in Ruby?
...a query that requests all of the items from the database ('select * from mytable') and then give you the number of items resulting, whereas .count will generate a single query ('select count(*) from mytable') which is considerably faster.
Because these ORMs are so prevalent I following the principl...
M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...
Calculate difference in keys contained in two Python dictionaries
...s:
diff = set(dictb.keys()) - set(dicta.keys())
Here is a class to find all the possibilities: what was added, what was removed, which key-value pairs are the same, and which key-value pairs are changed.
class DictDiffer(object):
"""
Calculate the difference between two dictionaries as:
...
Static class initializer in PHP
I have an helper class with some static functions. All the functions in the class require a ‘heavy’ initialization function to run once (as if it were a constructor).
...
Best way to allow plugins for a PHP application
... 5 = 9
4 * 5 = 20
Notes:
For this example source code, you must declare all your plugins before the actual source code that you want to be extendable. I've included an example of how to handle single or multiple values being passed to the plugin. The hardest part of this is writing the actual d...
How can I trim leading and trailing white space?
...ing white spaces when you read your data file. If you use read.csv or read.table you can set the parameterstrip.white=TRUE.
If you want to clean strings afterwards you could use one of these functions:
# Returns string without leading white space
trim.leading <- function (x) sub("^\\s+", "", x)
...
How to get a variable name as a string in PHP?
...
Actually now that I've tested my code, my code always returned 'var' because it's being used in the function. When I use $GLOBALS instead, it returns the correct variable name for some reason. So I'll change the above code to use...
Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...lly, setdiff(bigFrame, smallFrame) gets you the extra records in the first table.
In the SQLverse this is called a
For good descriptions of all join options and set subjects, this is one of the best summaries I've seen put together to date: http://www.vertabelo.com/blog/technical-articles/sq...
NSOperation vs Grand Central Dispatch
...les: bandwidth-constrained queues that only run N operations at a time; establishing dependencies between operations. Both very simple with NSOperation, very difficult with GCD.) Apple's done the hard work of leveraging GCD to create a very nice object-friendly API with NSOperation. Take advantage ...