Node acceleration

[mch_basim]

Hi
I want to record a node acceleration under an earthquake timeseries excitation. I have timeseries & it is not a multi-support case!

in last paragraph of this reference it said that: "For a UniformExcitation analysis, this command generates output file nodesA.out that contains absolute accelerations && NOTE that if no TimeSeries is provided and a uniform excitation analysis is performed, the relative accelerations are recorded." :
(which I have time series so it should be absolute!!)
http://opensees.berkeley.edu/wiki/index ... e_Recorder

but in this reference it is said that: " The responses obtained from the nodes for this type of excitation are RELATIVE values, and not the absolute values obtained from a multi-support case."
http://opensees.berkeley.edu/wiki/index ... on_Pattern

Please let me know which one is correct or I am misunderstanding!
My own examinations show that it is relative one.

thanks a lot.

[fmk]

if you do a uniform excitation analysis the response quantaties at the nodes are all relative. if you do a muli-support analysis the response quantaties are total.

the recorders, in the absence of a timeseries, simply record the information that is stored at the nodes. if you add a time series option, the results from the nodes are added to whatever the time series
value is for each particular step.