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LibGDX has a fairly simple setup, with the help of a simple Java program. You can find the download here. When you startup the application, it will look something like this: Note: This screenshot have been taken on Linux and shows path that differs from a Windows installation. However, the form is...

(loop for i from 0 to 10 do (print i)) ; prints 0 1 2 3 4 5 6 7 8 9 10 (loop for i from 0 below 10 do (print i)) ; prints 0 1 2 3 4 5 6 7 8 9 10 (loop for i from 10 above 0 do (print i)) ; prints 10 9 8 7 6 5 4 3 2 1 (loop for i from 10 to 0 do (print i)) ; prints noth...

Comparing sets In R, a vector may contain duplicated elements: v = "A" w = c("A", "A") However, a set contains only one copy of each element. R treats a vector like a set by taking only its distinct elements, so the two vectors above are regarded as the same: set...

The %in% operator compares a vector with a set. v = "A" w = c("A", "A") w %in% v # TRUE TRUE v %in% w # TRUE Each element on the left is treated individually and tested for membership in the set associated with the vector on the right (consisting of all its...

To count how many elements of two sets overlap, one could write a custom function: xtab_set <- function(A, B){ both <- union(A, B) inA <- both %in% A inB <- both %in% B return(table(inA, inB)) } A = 1:20 B = 10:30 xtab_set(A, B) # inB ...

Sets are unordered collections of distinct elements. But sometimes we want to work with unordered collections of elements that are not necessarily distinct and keep track of the elements' multiplicities. Consider this example: >>> setA = {'a','b','b','c'} >>> setA set(['a', 'c'...

Like maps, sets are associative and unordered. Unlike maps, which contain mappings from keys to values, sets essentially map from keys to themselves. A set is denoted by curly braces preceded by an octothorpe: #{} ;;=> #{} #{:foo} ;;=> #{:foo} #{:foo :bar} ;;=> #{:bar :foo} As...

Using the dateutil library as in the previous example on parsing timezone-aware timestamps, it is also possible to parse timestamps with a specified "short" time zone name. For dates formatted with short time zone names or abbreviations, which are generally ambiguous (e.g. CST, which coul...

By default all datetime objects are naive. To make them timezone-aware, you must attach a tzinfo object, which provides the UTC offset and timezone abbreviation as a function of date and time. Fixed Offset Time Zones For time zones that are a fixed offset from UTC, in Python 3.2+, the datetime mod...

It is possible to extract a date out of a text using the dateutil parser in a "fuzzy" mode, where components of the string not recognized as being part of a date are ignored. from dateutil.parser import parse dt = parse("Today is January 1, 2047 at 8:21:00AM", fuzzy=True) pr...

When trying to select from a table called order like this select * from order the error rises: Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'order' at line 1 Reserved keywords in MySQ...

Each enum class contains an implicit static method named values(). This method returns an array containing all values of that enum. You can use this method to iterate over the values. It is important to note however that this method returns a new array every time it is called. public enum Day { ...

Django default project layout creates a single settings.py. This is often useful to split it like this: myprojectroot/ myproject/ __init__.py settings/ __init__.py base.py dev.py prod.py tests.py This enables...

Django manger is an interface through which the django model queries the database. The objects field used in most django queries is actually the default manager created for us by django (this is only created if we don't define custom managers). Why would we define a custom manager/queryset? To avo...

package main import ( "log" "text/template" "os" ) type Person struct{ MyName string MyAge int } var myTempContents string= ` This person's name is : {{.MyName}} And he is {{.MyAge}} years old. ` func main() { t,err := temp...

When you want to use user generated content in the SQL, it with done with parameters. For example for searching user with the name aminadav you should do: var username = 'aminadav'; var querystring = 'SELECT name, email from users where name = ?'; connection.query(querystring, [username], functi...

You send the query as a string and in response callback with the answer is received. The callback gives you error, array of rows and fields. Each row contains all the column of the returned table. Here is a snippet for the following explanation. connection.query('SELECT name,email from users', fu...

Retrofit requests can be logged using an intercepter. There are several levels of detail available: NONE, BASIC, HEADERS, BODY. See Github project here. Add dependency to build.gradle: compile 'com.squareup.okhttp3:logging-interceptor:3.8.1' Add logging interceptor when creating Retrofit:...

MSDN: The return statement terminates execution of the method in which it appears and returns control to the calling method. It can also return an optional value. If the method is a void type, the return statement can be omitted. public int Sum(int valueA, int valueB) { return valueA +...

SharedPreferences Manager (Singleton) class to read and write all types of data. import android.content.Context; import android.content.SharedPreferences; import android.util.Log; import com.google.gson.Gson; import java.lang.reflect.Type; /** * Singleton Class for accessing SharedPref...