# Why TRUE == "TRUE" is TRUE in R?

RBooleanComparisonBoolean Logic## R Problem Overview

- Why
`TRUE == "TRUE"`

is`TRUE`

in R? - Is there any equivalent for
`===`

in R?

**Update:**

These are all returning `FALSE`

:

```
TRUE == "True"
TRUE == "true"
TRUE == "T"
```

The only `TRUE`

value is `TRUE == "TRUE"`

.

In case of checking with `identical()`

everything works fine.

**Second Update:**

By `===`

operator I meant the process of checking the *Value* and the *Data Type* of a *variable*. In this case I assumed that the `==`

operator will only compare the *Values* of variables, not their *Data Type* as well.

## R Solutions

## Solution 1 - R

According to the help file `?`==` `

:

>If the two arguments are atomic vectors of different types, one is coerced to the type of the other, the (decreasing) order of precedence being character, complex, numeric, integer, logical and raw.

So `TRUE`

is coerced to `"TRUE"`

(i. e. `as.character(TRUE)`

), hence the equality.

The equivalent of an operator `===`

in some other language (i. e. are the two objects equal and of the same type) would be function `identical`

:

```
identical(TRUE, "TRUE")
[1] FALSE
```

## Solution 2 - R

TRUE and FALSE are reserved words in R. I don't think eznme was correct (before his edit) when he said any non-zero value was TRUE, since `TRUE == "A"`

evaluates to FALSE. (That would have been correct in explaining why `TRUE == 1`

evaluates to TRUE, but it would not explain the result for `TRUE == 7`

The explanation given by plannapus was taken out of the context of describing the behavior of `as.logical`

. It is closer to the "truth", because it is the implicit coercion of TRUE to character by the `==`

operator that creates this result. Although `T`

and `F`

are initially given the values of TRUE and FALSE, they can be reassigned to other values or types.

```
> TRUE == as.logical( c("TRUE", "T", "true", "True") )
[1] TRUE TRUE TRUE TRUE
> TRUE == 7
[1] FALSE
> TRUE == as.logical(7)
[1] TRUE
> TRUE == as.logical("A")
[1] NA
```

(I earlier incorrectly wrote that the coercion induced by TRUE == "TRUE" was to logical; it's actually via as.character(TRUE) returning "TRUE".)

## Solution 3 - R

In addition to

TRUE == "TRUE"

these are also true:

- TRUE==1
- TRUE==1.0
- TRUE==1.0000000000000001
- TRUE==0.99999999999999999 etc, in general also all values close enough to 1.0 to be IEEE754-rounded to it.

But what is more interesing is what ** if()** checks: it checks

`non-false`

; in fact this plots!:```
if(4.0) plot(1)
```

I think the only values that dont trigger `if()`

are 0, F, FALSE and "FALSE" they seem defined as exactly 0.