Recorder Commands

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This command is used to generate a recorder object which is to monitor what is happening during the analysis and generate output for the user.

recorder recorderType? arg1? ...
To record the nodal response and response sensitivity, the most commonly used format is:
recorder Node -file disp29.out -time -node 29 -dof 1 <–precision 16 > disp
recorder Node -file ddm29G1.out -time -node 29 -dof 1 "sensitivity 1"
recorder Node -file ddm29G1.out -time -node 29 -dof 1 "velSensitivity 1"
recorder Node -file ddm29G1.out -time -node 29 -dof 1 "accSensitivity 1"


The above ‘recorder’ commands (extended for recording response sensitivities) save into files (with the file name defined after : the command ‘-file’) the responses and response sensitivities of the node 29 along the first degree of freedom (dof) direction. : Response quantities can be ‘disp’ (displacements), ‘vel’ (velocities) and ‘acc’ (accelerations). Response sensitivities are
denoted by a string in double quotes and containing the response quantity identifier (i.e., “sensitivity” for displacements,
“velSensitivity” for velocities and “accSensitivity” for accelerations) and the sensitivity parameter specified by the parameter : tag ( in this example the tag is 1).
The command ‘-precision’ is optional, and allows users to change the number of digits used to record into file the response
and/or response sensitivities. This command is particularly useful when the finite difference method is used to verify/validate : DDM-based FE response sensitivities, since high accuracy in the results may be needed.


The user may also get responses and response sensitivities directly using the following Tcl commands:
nodeDisp 29 1
nodeVel 29 1
nodeAccel 29 1
sensNodeDisp 29 1 2
sensNodeVel 29 1 2
sensNodeAccel 29 1 2
These commands return the responses of the node 29 along the first dof, and their response sensitivities with respect to the
parameter with tag 2