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ggobi
GGobi is an open source visualization program for exploring high-dimensional data. It provides highly dynamic and interactive graphics such as tours, as well as familiar graphics such as the scatterplot, barchart and parallel coordinates plots. Plots are interactive and linked with brushing and identification.
NGSPICE
Spice is a general-purpose electric circuit simulation program for nonlinear dc, nonlinear transient and linear ac analysis.
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