Tutorial by Topics: roc

All preprocessor commands begins with the hash (pound) symbol #. A C macro is just a preprocessor command that is defined using the #define preprocessor directive. During the preprocessing stage, the C preprocessor (a part of the C compiler) simply substitutes the body of the macro wherever its nam...

Proc.new(block) lambda { |args| code } ->(arg1, arg2) { code } object.to_proc { |single_arg| code } do |arg, (key, value)| code end Be careful about operator precedence when you have a line with multiple methods chained, like: str = "abcdefg" puts str.gsub(/./) do |mat...

Use context processors to add variables that are accessible anywhere in your templates. Specify a function, or functions that return dicts of the variables you want, then add those functions to TEMPLATE_CONTEXT_PROCESSORS.

Scollector can be used to monitor processes and services in Windows and Linux. Some processes like IIS application pools are monitored automatically, but usually you need to specify which processes and services you want to monitor.

#define [symbol] // Defines a compiler symbol. #undef [symbol] // Undefines a compiler symbol. #warning [warning message] // Generates a compiler warning. Useful with #if. #error [error message] // Generates a compiler error. Useful with #if. #line [line number] (file name) // Overrides the co...

The C preprocessor is a simple text parser/replacer that is run before the actual compilation of the code. Used to extend and ease the use of the C (and later C++) language, it can be used for: a. Including other files using #include b. Define a text-replacement macro using #define c. Conditional...

Functions and subroutines, in conjunction with modules, are the tools to break down a program into units. This makes the program more readable and manageable. Each one of these units can be thought of as part of the code that, ideally, could be compiled and tested in isolation. The main program(s...

$PSCmdlet.ShouldProcess("Target") $PSCmdlet.ShouldProcess("Target", "Action") ParameterDetailsTargetThe resource being changed.ActionThe operation being performed. Defaults to the name of the cmdlet. $PSCmdlet.ShouldProcess() will also automatically write a m...

IdentifierName [arguments] Call IdentifierName[(arguments)] [Let|Set] expression = IdentifierName[(arguments)] [Let|Set] IdentifierName[(arguments)] = expression ParameterInfoIdentifierNameThe name of the procedure to call.argumentsA comma-separated list of arguments to be passed to the p...

ParameterDetailsRETURNSSpecifies the data type that can be returned from a function.RETURNActual variable or value following the RETURN syntax is what is returned to where the function was called from. A stored routine is either a procedure or a function. A procedure is invoked using a CALL st...

subprocess.call(args, *, stdin=None, stdout=None, stderr=None, shell=False, timeout=None) subprocess.Popen(args, bufsize=-1, executable=None, stdin=None, stdout=None, stderr=None, preexec_fn=None, close_fds=True, shell=False, cwd=None, env=None, universal_newlines=False, startupinfo=None, creati...

Parallelization on remote machines require libraries to be downloaded on each machine. Prefer package::function() calls. Several packages have parallelization natively built-in, including caret, pls and plyr. Microsoft R Open (Revolution R) also uses multi-threaded BLAS/LAPACK libraries which int...

Stored Procedures are SQL statements stored in the database that can be executed or called in queries. Using a stored procedure allows encapsulation of complicated or frequently used logic, and improves query performance by utilizing cached query plans. They can return any value a standard query c...

Gaussian Blur Syntax C++: void GaussianBlur(InputArray src, OutputArray dst, Size ksize, double sigmaX, double sigmaY=0, int borderType=BORDER_DEFAULT ) Parameters of Gaussian BlurDetailssrcInput image, the image can have any number of channels, which are processed independently, but the dep...

always @ (posedge clk) begin /* statements */ end always @ (negedge clk) begin /* statements */ end always @ (posedge clk or posedge reset) // may synthesize less efficiently than synchronous reset

PLSQL procedure is a group of SQL statements stored on the server for reuse. It increases the performance because the SQL statements do not have to be recompiled every time it is executed. Stored procedures are useful when same code is required by multiple applications. Having stored procedures eli...