The R-value of some insulations also depends on temperature, aging, and moisture accumulation. When calculating the R-value of a multilayered installation, add the R-values of the individual layers. Installing more insulation in your home increases the R-value and the resistance to heat flow.
R has several operators to perform tasks including arithmetic, logical and bitwise operations. In this article, you will learn about different R operators with the help of examples.
R has many operators to carry out different mathematical and logical operations.
Operators in R can mainly be classified into the following categories.
| Arithmetic operators |
| Relational operators |
| Logical operators |
| Assignment operators |
Enter Your Numbers: First number Second number Third number Fourth number. Number of Draws shown: 10 20 Past year's draws. Search by Date: From 4/11/2020. Please visit this link since your browser does not support frames. When you produce reports in R, you will want your numbers to appear all nicely formatted to enhance the impact of your data on the viewer. You can use format to turn your numbers into pretty text, ready for printing. This function takes a number of arguments to control the format of your result.
R Arithmetic Operators
These operators are used to carry out mathematical operations like addition and multiplication. Here is a list of arithmetic operators available in R.
| Operator | Description |
|---|---|
| + | Addition |
| – | Subtraction |
| * | Multiplication |
| / | Division |
| ^ | Exponent |
| %% | Modulus (Remainder from division) |
| %/% | Integer Division |
An example run
R Relational Operators
Relational operators are used to compare between values. Here is a list of relational operators available in R.
| Operator | Description |
|---|---|
| < | Less than |
| > | Greater than |
| <= | Less than or equal to |
| >= | Greater than or equal to |
| Equal to | |
| != | Not equal to |
An example run
Operation on Vectors
The above mentioned operators work on vectors. The variables used above were in fact single element vectors.
We can use the function c() (as in concatenate) to make vectors in R.
All operations are carried out in element-wise fashion. Here is an example.
When there is a mismatch in length (number of elements) of operand vectors, the elements in shorter one is recycled in a cyclic manner to match the length of the longer one.
R will issue a warning if the length of the longer vector is not an integral multiple of the shorter vector.
R Logical Operators
Logical operators are used to carry out Boolean operations like AND, OR etc.
| Operator | Description |
|---|---|
| ! | Logical NOT |
| & | Element-wise logical AND |
| && | Logical AND |
| | | Element-wise logical OR |
| || | Logical OR |
Operators & and | perform element-wise operation producing result having length of the longer operand.
But && and || examines only the first element of the operands resulting into a single length logical vector.
Zero is considered FALSE and non-zero numbers are taken as TRUE. An example run.
R Assignment Operators
These operators are used to assign values to variables.
| Operator | Description |
|---|---|
| <-, <<-, = | Leftwards assignment |
| ->, ->> | Rightwards assignment |
The operators <- and = can be used, almost interchangeably, to assign to variable in the same environment.
The <<- operator is used for assigning to variables in the parent environments (more like global assignments). The rightward assignments, although available are rarely used.
R Number Of Rows
Check out these examples to learn more:
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R Operator Precedence and Associativity
The original view of oxidation and reduction is that of adding or removing oxygen . An alternative approach is to describe oxidation as the loss of hydrogen and reduction as the gaining of hydrogen. This has an advantage in describing the burning of methane.
With this approach it is clear that the carbon is oxidized (loses all four hydrogens) and that part of the oxygen is reduced (gains hydrogen). Another reaction where the hydrogen approach makes things clearer is the passing of methanol over a hot copper gauze to form formaldehyde and hydrogen gas (Hill and Kolb):
R Number For Coronavirus
Both carbon-containing molecules have the same oxygen content, but the formation of the formaldehyde is seen to be oxidation because hydrogens are lost. The formation of H2 is a reduction process as the two released hydrogens get together.
The formation of methanol from reacting carbon monoxide with hydrogen combines oxidation and reduction in the single molecular product.
The CO is reduced because it gains hydrogen, and the hydrogen is oxidized by its association with the oxygen.