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Units[Simple]

  

ln

  

natural logarithmic function in the Simple Units environment

  

log

  

general logarithmic function in the Simple Units environment

  

log10

  

common logarithmic function in the Simple Units environment

 

Calling Sequence

Parameters

Description

Examples

Calling Sequence

ln(expr)

 

log(expr)

 

log10(expr)

 

log[b](expr)

logbexpr

Parameters

expr

-

algebraic expression

b

-

algebraic expression, the base of the logarithm

Description

• 

In the Simple Units environment, any verifications of valid dimensions ignore so-called Unit annotations.

• 

In the Simple Units environment, the arguments for the logarithmic functions must be unit-free, and so is the result. If you would like the results to have a unit in the dimension of logarithmic gain, consider using the Standard Units environment.

• 

Every command in the Simple Units environment that needs to determine whether an expression is valid or not, does so using the Units[TestDimensions] command.

• 

For other properties, see the global function ln.

Examples

Notes: 

– 

To enter a unit in 2-D Math input, select the unit from the appropriate Units palette. If the unit you want is not there, select unit and then enter the unit.

– 

When you edit a unit, double brackets appear around it.

withUnitsSimple:

This input results in an error.

ln5.3m

Error, (in Units:-Simple:-ln) the following expressions imply incompatible dimensions: {ln(5.3*Units:-Unit(m))}

However, the following can be legal: if a has the dimension 1length, then the argument to the ln function, am, is unit-free.

vallnam

vallnam

(1)

For example, diopter is a unit with the dimension 1length.

vala=7.5diopter|vala=7.5diopter

2.014903021

(2)

Conversely, if we evaluate at a float value for a, then the original error is triggered.

vala=5.3|vala=5.3

Error, (in Units:-Simple:-eval) the following expressions imply incompatible dimensions: {ln(5.3*Units:-Unit(m))}

See Also

ln

Units

Units/logarithmic_gain

Units/Simple