Basic Examples (3) 

Reproduce a basic Log identity:

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Find conditions for which Log[a]-Log[b] is equal to Log[a/b]:

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Contract logs, disregarding branch cut issues:

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The result is not generically true:

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Scope (2) 

LogContract automatically threads over equations:

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LogContract is essentially the inverse of PowerExpand for logarithmic expressions:

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Contracting to the original expression:

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Options (2) 

Assumptions (2) 

The default option setting for Assumptions is $Assumptions. By default $Assumptions=True, meaning that LogContract gives a universally correct result:

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With the setting Automatic, a maximal set of assumptions are used and the output is not generically correct:

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A simpler result is obtained with suitable assumptions:

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Contract logs assuming real arguments:

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Possible Issues (1) 

The default option for LogContract is Assumptions→True, unlike PowerExpand which uses Automatic as the default:

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