Path

A path time series is defined by a list of times and a list of values, with linear interpolation between them. It reproduces arbitrary signals: recorded ground motions, measured forces, anything you can express as numbers.

🔧 Grasshopper component

Path Time SeriesAlpaca4d ▸ 04_Time Series

Inputs

TimesNumberlistTimes $t_i$, in s. Ascending, and the same count as Values.

ValuesNumberlistLoad factors ${\lambda }_i$ at those times.

LoadFactorNumber1.0Global scale $c_{\text{factor}}$ applied to all values.

Outputs

TimeSeriesTimeSeriesPath series, for a Load Pattern.

GraphNumberlistThe values, for plotting.

📈 When to use it

Use it when

• You need a recorded time history — earthquake acceleration, a measured force or displacement.
• The signal is generated in Grasshopper and is not analytic.
• You want full control over the shape of the excitation.

Do not use it when

• The signal lives in a file → Read Time Series parses it for you.
• A constant or a ramp will do → Constant or Linear.
• The loading is purely harmonic → Trigonometric is one number instead of a list.

🔗 Relation to OpenSees

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

-useLast is always written: past the last time in the list, the factor holds at the final value rather than dropping to zero. If you want the excitation to stop, end the list with a zero.