Tutorial by Examples: calc

package com.example; import android.os.Bundle; import android.support.annotation.Nullable; import android.util.Log; import android.view.View; import android.view.ViewTreeObserver; public class ExampleActivity extends Activity { @Override protected void onCreate(@Nullable final ...

#include <stdio.h> #include <stdlib.h> #include <string.h> int main(int argc, char **argv) { /* Exit if no second argument is found. */ if (argc != 2) { puts("Argument missing."); return EXIT_FAILURE; } size_t len = str...

Factorials can be computed at compile-time using template metaprogramming techniques. #include <iostream> template<unsigned int n> struct factorial { enum { value = n * factorial<n - 1>::value }; }; template<> struct factorial<0> { ...

If a remote branch has been deleted, your local repository has to be told to prune the reference to it. To prune deleted branches from a specific remote: git fetch [remote-name] --prune To prune deleted branches from all remotes: git fetch --all --prune

To publish the changes you made in your working copy, run the svn commit command. IMPORTANT: Review your changes before committing them! Use svn status and svn diff to review the changes. Also, make sure you are in the correct path before performing a commit. If you updated many files across vari...

Each individual CSS Selector has its own specificity value. Every selector in a sequence increases the sequence's overall specificity. Selectors fall into one of three different specificity groups: A, B and c. When multiple selector sequences select a given element, the browser uses the styles appli...

When local changes are present, the git pull command aborts reporting : error: Your local changes to the following files would be overwritten by merge In order to update (like svn update did with subversion), you can run : git stash git pull --rebase git stash pop A convenient way coul...

// Java: Arrays.stream(new int[] {1, 2, 3}) .map(n -> 2 * n + 1) .average() .ifPresent(System.out::println); // 5.0 // Kotlin: arrayOf(1,2,3).map { 2 * it + 1}.average().apply(::println)

5.1 .some and .every allow a logical connective of Array values. While .some combines the return values with OR, .every combines them with AND. Examples for .some [false, false].some(function(value) { return value; }); // Result: false [false, true].some(function(value) { return value...

Numerical comparisons use the -eq operators and friends if [[ $num1 -eq $num2 ]]; then echo "$num1 == $num2" fi if [[ $num1 -le $num2 ]]; then echo "$num1 <= $num2" fi There are six numeric operators: -eq equal -ne not equal -le less or equal -lt less than ...

Units of measure are additional type annotations that can be added to floats or integers. They can be used to verify at compile time that calculations are using units consistently. To define annotations: [<Measure>] type m // meters [<Measure>] type s // seconds [<Measure>] typ...

Two std::strings can be compared lexicographically using the operators ==, !=, <, <=, >, and >=: std::string str1 = "Foo"; std::string str2 = "Bar"; assert(!(str1 < str2)); assert(str > str2); assert(!(str1 <= str2)); assert(str1 >= str2); assert...

A common use case for wanting to calculate the frame a label will take up is for sizing table view cells appropriately. The recommended way of doing this is using the NSString method boundingRectWithSize:options:attributes:context:. options takes String drawing options: NSStringDrawingUsesLineFr...

With C++11 and higher calculations at compile time can be much easier. For example calculating the power of a given number at compile time will be following: template <typename T> constexpr T calculatePower(T value, unsigned power) { return power == 0 ? 1 : value * calculatePower(value,...

By recursion let rec sumTotal list = match list with | [] -> 0 // empty list -> return 0 | head :: tail -> head + sumTotal tail The above example says: "Look at the list, is it empty? return 0. Otherwise it is a non-empty list. So it could be [1], [1; 2], [1; 2; 3] ...

Accepts a mathematical expression and returns a numerical value. It is especially useful when working with different types of units (e.g. subtracting a px value from a percentage) to calculate the value of an attribute. +, -, /, and * operators can all be used, and parentheses can be added to spec...

The MEDIAN function since Oracle 10g is an easy to use aggregation function: SELECT MEDIAN(SAL) FROM EMP It returns the median of the values Works on DATETIME values too. The result of MEDIAN is computed by first ordering the rows. Using N as the number of rows in the group, Oracle calcula...

In normal mode, we can increment the nearest number on the line at or after the cursor with <C-a> and decrement it with <C-x>. In the following examples, the cursor position is indicated by ^. Incrementing and decrementing numbers for i in range(11): ^ <C-x> decrements ...

The hashlib module allows creating message digest generators via the new method. These generators will turn an arbitrary string into a fixed-length digest: import hashlib h = hashlib.new('sha256') h.update(b'Nobody expects the Spanish Inquisition.') h.digest() # ==> b'.\xdf\xda\xdaVR[\x12\...

The command git svn dcommit will create a SVN revision for each of your local git commits. As with SVN, your local git history must be in sync with the latest changes in the SVN repository, so if the command fails, try performing a git svn rebase first.