How do I ‌put x and y values as data input in R programming?

In constructing relationship between x and y, we create a table with two columns, with x in the first column and corresponding y in the second column. The value of x may be discrete (numeric or non-numeric) or continuous(numeric) and y is numeric. A graph with x and y represents the table of values.
In the following there are six categories (A through F) and for each of these categories a value has been assigned (67,47,11,12,22,24). Now how do I create a data in R that I could work on?
This is easily carried out by creating a data frame as shown:

> dap <- br="" data.frame="">+  x=factor(c("A","B","C","D","E","F"), levels=c("A","B","C","D","E","F")),
+ ItmVal=c(69,47,11,12,42,24)
-----------------------------------

DataFrameDiscrete.png

What are mutable and immutable variables in F#?

If I assign a value to a variable and then later in the program I assign another value to the same varible the program does not care if it is a mutable variable. However if it is immutable, the program does not accept it. Hence immutable variable is one which is solidly bound to its value.

Let me take you to the .NET Fiddle site so that you can run it yourself and see the result.

First of all assignment to a variable in F# has the following syntax:

let x=25
 
The above statement assigns a value 25 to the variable x. I can print it to the screen using the second statement (printfn "x: %i" x) because x is an integer.

Next I assign a value of 45. You can see the error in this statement immediately. Hence value of x is immutable.

Now how can I assign a mutable value?

Well, F# uses the keyword mutable as shown here:

let mutable x=15

Now x has a value which can be changed later as shown in the next image. The first statement sets a value 15 for the variable x and the second statement prints it.

The third statement assigns a new value to it, namely 20 and the fourth line prints it. Observe carefully the new value assignment, a backward going arrow.

What are variables in C++ and how do you declare them?

Please review this previous post before you dig into this post.

A variable is a portion of the memory to store a value very similar to your pigeon-hole in your mail office at work.

PigeonHole.png

This picture shows all mailboxes of same size, in C++ and other programming languages you have variables of different sizes and the above analogy has to be modified. The idea that a variable indicates the storage in memory is valid.

In order to declare a variable you need a name and type. The name can be anything other than the names reserved for its (C++ Program) use. You can find them in references (for example: http://cs.smu.ca/~porter/csc/ref/cpp_keywords.html).

The type however, depends on what the variable stands for, such as, is it an integer or a floating point; is it a single character or a bunch of characters; does it represent time in some fashion? etc.

Declaring variable that are integers

The following three lines declare three integers

int a;
int z;
int axc;

The following line declares 3 integers as well. Note that to declare in a single line all of them should be of the same type. This is a short hand for declaring more than one variable.

int result1, result2, result3;

Just declaring a variable is not enough, to work a program, you need to provide a value to the variable, that is called assigning a value.3

Assuming you declared variables as indicated earlier, now the following lines assign values to them:

a=6;
z=19;
axc=1500;

Once you have a bunch of varibales declared and assigned as above you can operate on them in various ways;

result1=a+z; //(this should produce the result 25
result2=axc/(a+z);//(this should produce the result 60)
result3=axc/100;// (this should produce 15)

Here the operators are + (add), and / (divided by)

Now this is all put inside a project called Variables_01 as shown using Visual Studio Express 2015 for Windows Desktop. Of course you can use any other program with C++ compiler.

I assume you reviewed the post mentioned earlier, if not go back and review.

You need to reference in your stdafx.h file as shown:
-----------------
// stdafx.h : include file for standard system include files,
// or project specific include files that are used frequently, but
// are changed infrequently
//
#pragma once
#include "targetver.h"
#include
#include
#include
-----------------------

Variables_01

Build and run this program, the result displayed as shown.

Variables_01_1