I'm not sure I'm clear on all the requirements, but if the time intervals are known and consistent for each index, meaning you won't need to store them, you could: 
push( @{$log[$error_type_index]}, $error_count );

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In reply to Re: How to create a non uniform multi-dimention array with push? by state-o-dis-array
in thread How to create a non uniform multi-dimention array with push? by shaialo

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