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Read Time Series ​

Reads a Path time series from a text file on disk. It is the practical way to get a recorded ground motion into a model — an earthquake record, a measured force history, a wind signal.

🔧 Grasshopper component ​

Read Time SeriesAlpaca4d ▸ 04_Time Series
Read Time Series component
Inputs
FilePathTextPath to the file. Each line must hold one time–value pair.
SeparatorText,The single character separating time from value.
Use \t for tab-separated files by typing a literal tab, or for space-separated.
Outputs
TimeSeriesTimeSeriesA Path time series, for a Load Pattern.
GraphNumberlistThe values, for plotting.

File format ​

One record per line, time first, value second:

0.000,0.0012
0.005,0.0034
0.010,-0.0021

Every line must split into at least two fields with the given separator, or the component throws and names the offending line. There is no header row and no comment syntax — strip those first.

Note

The values are read verbatim, with no scale factor. A ground-motion record in g has to be multiplied by 9.81 somewhere — either in the file, or on the Factor input of the Load Pattern.

📈 When to use it ​

Use it when

  • The signal already exists as a file, and you would rather not paste thousands of numbers into Grasshopper.
  • You are running several records through the same model — swap the path, rerun.

Do not use it when

  • The signal is generated in Grasshopper → feed it straight into Path.
  • The signal is analytic → Trigonometric or Linear is clearer and has nothing to go stale on disk.

🔗 Relation to OpenSees

Identical to Path — the file is parsed by Alpaca4d, not by OpenSees:

tcl
timeSeries Path $tag -time {t1 t2 ... tn} -values {v1 v2 ... vn} -factor $cFactor -useLast