Tutorial by Examples: en

The MATLAB Profiler is a tool for software profiling of MATLAB code. Using the Profiler, it is possible to obtain a visual representation of both execution time and memory consumption. Running the Profiler can be done in two ways: Clicking the "Run and Time" button in the MATLAB GUI...

One might want to group their data by the runs of a variable and perform some sort of analysis. Consider the following simple dataset: (dat <- data.frame(x = c(1, 1, 2, 2, 2, 1), y = 1:6)) # x y # 1 1 1 # 2 1 2 # 3 2 3 # 4 2 4 # 5 2 5 # 6 1 6 The variable x has three runs: a run of l...

if ($PSCmdlet.ShouldProcess("Target of action")) { # Do the thing } When using -WhatIf: What if: Performing the action "Invoke-MyCmdlet" on target "Target of action" When using -Confirm: Are you sure you want to perform this action? Performing operation &qu...

One std::vector can be append to another by using the member function insert(): std::vector<int> a = {0, 1, 2, 3, 4}; std::vector<int> b = {5, 6, 7, 8, 9}; a.insert(a.end(), b.begin(), b.end()); However, this solution fails if you try to append a vector to itself, because the sta...

The data.table package provides a convenient way to group by runs in data. Consider the following example data: library(data.table) (DT <- data.table(x = c(1, 1, 2, 2, 2, 1), y = 1:6)) # x y # 1: 1 1 # 2: 1 2 # 3: 2 3 # 4: 2 4 # 5: 2 5 # 6: 1 6 The variable x has three runs: a run ...

The where statement may be used within a switch case match to add additional criteria required for a positive match. The following example checks not only for the range, but also if the number is odd or even: switch (temperature) { case 0...49 where temperature % 2 == 0: print(&quot...

A string representation of a Guid can be obtained by using the built in ToString method string myGuidString = myGuid.ToString(); Depending on your needs you can also format the Guid, by adding a format type argument to the ToString call. var guid = new Guid("7febf16f-651b-43b0-a5e3-0da8da4...

R is able to access the current date, time and time zone: Sys.Date() # Returns date as a Date object ## [1] "2016-07-21" Sys.time() # Returns date & time at current locale as a POSIXct object ## [1] "2016-07-21 10:04:39 CDT" as.numeric(Sys...

If you wish to copy the contents of a slice into an initially empty slice, following steps can be taken to accomplish it- Create the source slice: var sourceSlice []interface{} = []interface{}{"Hello",5.10,"World",true} Create the destination slice, with: Length =...

A 16-byte GUID / UUID. DECLARE @GUID UNIQUEIDENTIFIER = NEWID(); SELECT @GUID -- 'E28B3BD9-9174-41A9-8508-899A78A33540' DECLARE @bad_GUID_string VARCHAR(100) = 'E28B3BD9-9174-41A9-8508-899A78A33540_foobarbaz' SELECT @bad_GUID_string, -- 'E28B3BD9-9174-41A9-8508-899A78A33540_foobarbaz' ...

Long vectors with long runs of the same value can be significantly compressed by storing them in their run-length encoding (the value of each run and the number of times that value is repeated). As an example, consider a vector of length 10 million with a huge number of 1's and only a small number o...

static class Program { static void Main() { dynamic dynamicObject = new ExpandoObject(); string awesomeString = "Awesome"; // Prints True Console.WriteLine(awesomeString.IsThisAwesome()); dynamicObject.StringValue = awesomeStrin...

std::enable_if is a convenient utility to use boolean conditions to trigger SFINAE. It is defined as: template <bool Cond, typename Result=void> struct enable_if { }; template <typename Result> struct enable_if<true, Result> { using type = Result; }; That is, enable_...

A React component can be defined as an ES6 class that extends the base React.Component class. In its minimal form, a component must define a render method that specifies how the component renders to the DOM. The render method returns React nodes, which can be defined using JSX syntax as HTML-like ta...

The -Regex parameter allows switch statements to perform regular expression matching against conditions. Example: switch -Regex ('Condition') { 'Con\D+ion' {'One or more non-digits'} 'Conditio*$' {'Zero or more "o"'} 'C.ndition' {'Any single char.'} '^C\w+ition$'...

The -Wildcard parameter allows switch statements to perform wildcard matching against conditions. Example: switch -Wildcard ('Condition') { 'Condition' {'Normal match'} 'Condit*' {'Zero or more wildcard chars.'} 'C[aoc]ndit[f-l]on' {'Range and set of chars...

The -Exact parameter enforces switch statements to perform exact, case-insensitive matching against string-conditions. Example: switch -Exact ('Condition') { 'condition' {'First Action'} 'Condition' {'Second Action'} 'conditioN' {'Third Action'} '^*ondition$' {'Fourth Action...

The -CaseSensitive parameter enforces switch statements to perform exact, case-sensitive matching against conditions. Example: switch -CaseSensitive ('Condition') { 'condition' {'First Action'} 'Condition' {'Second Action'} 'conditioN' {'Third Action'} } Output: Second Act...

The -file parameter allows the switch statement to receive input from a file. Each line of the file is evaluated by the switch statement. Example file input.txt: condition test Example switch statement: switch -file input.txt { 'condition' {'First Action'} 'test' {'Second Action...

The Arbitrary class is for types that can be randomly generated by QuickCheck. The minimal implementation of Arbitrary is the arbitrary method, which runs in the Gen monad to produce a random value. Here is an instance of Arbitrary for the following datatype of non-empty lists. import Test.QuickC...