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Contents

Index

• Getting Started

• User's Guide

• Desktop Tools and Development Environment

• Data Import and Export

• Mathematics

• Arrays and Matrices

• Linear Algebra

• Elementary Math

• Trigonometric

• Exponential

• Rounding and Remainder

• Discrete Math

• Polynomials

• Interpolation and Computational Geometry

• Cartesian Coordinate System Conversion

• Nonlinear Numerical Methods

• Special Functions

• Sparse Matrices

• Math Constants

• Data Analysis

• Programming and Data Types

• Object-Oriented Programming

• 3-D Visualization

• GUI Development

• External Interfaces

• Release Notes

log - Natural logarithm

Syntax

Y = log(X)

Description

The log function operates element-wise on arrays. Its domain includes complex and negative numbers, which may lead to unexpected results if used unintentionally.

Y = log(X) returns the natural logarithm of the elements of X. For complex or negative z where z = x + y*i, the complex logarithm is returned.

log(z) = log(abs(z)) + i*atan2(y,x)

Examples

The statement abs(log(-1)) is a clever way to generate π.

ans =

    3.1416

See Also

exp | log10 | log2 | logm | reallog

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