The ≠ Command

notequal.png

Command Summary

Tests if two values are different.

Command Syntax

value1value 2

Menu Location

Press [♦][=] key to enter ≠.

Calculator Compatibility

This command works on all calculators.

Token Size

1 byte

The ≠ operator compares two values, returning true if they're different, and false if they're equal. It is a basic building block of the conditions used by commands such as If, when(), and While. The results of ≠ and the other relational operators (=, >, , <, and ) can be combined with the and, or, xor, and not operators to create more complicated conditions.

It returns a single value for most types of data, and returns true if the two sides are mismatched in type: comparing a single number to a list, for instance, or comparing two lists that are of a different size. The only exception is when comparing two lists or two matrices of the same size: in that case, it compares them element-by-element, and returns a list or matrix of true/false values.

:2+2≠4
           false
:2+2≠5
           true
:{1,2,3}≠{1,4,3}
           {false  true  false}

If either side or both contains undefined variables, ≠ will wait to return a value unless it's something clearly true or false for any value of the variable (for instance, x≠x). You can do math with the resulting inequality: if an operation makes sense, it will be applied to both sides: for instance, if x≠y, then you can negate it to get -x≠-y. An operation will not be applied to both sides if it wouldn't be consistent with the previous inequality: for example, you can't square both sides, since if x≠y it can still be the case that x^2=y^2. You can also extract the two halves of the inequality with left() and right().

Related Commands

  • = (equal)
  • > (greater than)
  • (greater than or equal)
  • < (less than)
  • (less than or equal)

See Also

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