# Direction

is an option for Limit and related functions that specifies the direction in which the limit is taken.

# Details

• Possible settings for Direction include:
•  Reals or "TwoSided" from both real directions "FromAbove" or -1 from above or larger values "FromBelow" or +1 from below or smaller values Complexes from all complex directions Exp[ θ] in the direction {dir1,…,dirn} use direction diri for variable xi independently
• DirectionExp[ θ] at x* indicates the direction tangent of a curve approaching the limit point x*.

# Examples

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## Basic Examples(1)

Limit from below:

Limit from above:

The two-sided limit does not exist:

## Scope(5)

One-sided limits at piecewise discontinuities:

The default direction is two sided:

One-sided max limits:

The default direction Reals gives the larger of the two one-sided max limits:

Visualize the function:

Limits at a simple pole:

Limits at a branch cut:

Compute the bivariate limit approach from different quadrants:

Approaching the origin from the first quadrant:

Equivalently:

Approaching the origin from the second quadrant:

Approaching the origin from the left half-plane:

Approaching the origin from the bottom half-plane:

Visualize the function:

## Properties & Relations(4)

The settings "FromBelow" and 1 are equivalent:

The settings "FromAbove" and -1 are equivalent:

The settings "TwoSided" and Reals are equivalent:

Direction places conditions on the limit variable:

Assumptions applies to parameters in the limit expression:

Wolfram Research (1991), Direction, Wolfram Language function, https://reference.wolfram.com/language/ref/Direction.html (updated 2017).

#### Text

Wolfram Research (1991), Direction, Wolfram Language function, https://reference.wolfram.com/language/ref/Direction.html (updated 2017).

#### CMS

Wolfram Language. 1991. "Direction." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2017. https://reference.wolfram.com/language/ref/Direction.html.

#### APA

Wolfram Language. (1991). Direction. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/Direction.html

#### BibTeX

@misc{reference.wolfram_2024_direction, author="Wolfram Research", title="{Direction}", year="2017", howpublished="\url{https://reference.wolfram.com/language/ref/Direction.html}", note=[Accessed: 02-August-2024 ]}

#### BibLaTeX

@online{reference.wolfram_2024_direction, organization={Wolfram Research}, title={Direction}, year={2017}, url={https://reference.wolfram.com/language/ref/Direction.html}, note=[Accessed: 02-August-2024 ]}