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I do a transient Simulation with many similar subcircuits. Each subcircuit has a current source on the Input.

For example the current source 49 is creating following Signal:

I49 r49 inp49 PWL REPEAT FOREVER( 0.200 9.36 0.201 5.62 0.399 5.62 0.400 9.36 2.200 9.36 ) ENDREPEAT

My Problem is I don' know why spice removes some PWL Points during simulation: This is what's written in the text file:

I49: Removing PWL point (2.2,9.36) 
I49: Removing PWL point (4.4,9.36)
I49: Removing PWL point (6.6,9.36)
I49: Removing PWL point (8.8,9.36)
I49: Removing PWL point (11,9.36)
I49: Removing PWL point (13.2,9.36)
I49: Removing PWL point (15.4,9.36)
I49: Removing PWL point (17.6,9.36)
I49: Removing PWL point (19.8,9.36)
I49: Removing PWL point (22,9.36)
I49: Removing PWL point (24.2,9.36)
I49: Removing PWL point (26.4,9.36)
I49: Removing PWL point (28.6,9.36)
I49: Removing PWL point (30.8,9.36)
I49: Removing PWL point (33,9.36)
I49: Removing PWL point (35.2,9.36)
I49: Removing PWL point (37.4,9.36)
I49: Removing PWL point (39.6,9.36)
I49: Removing PWL point (41.8,9.36)
I49: Removing PWL point (44,9.36)
I49: Removing PWL point (46.2,9.36)
I49: Removing PWL point (48.4,9.36)
I49: Removing PWL point (50.6,9.36)
I49: Removing PWL point (52.8,9.36)
I49: Removing PWL point (55,9.36)
I49: Removing PWL point (57.2,9.36)
I49: Removing PWL point (59.4,9.36)
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    \$\begingroup\$ Providing a minimal .asc file that exhibits this behaviour would be good for people to have a look for themselves. \$\endgroup\$ – PlasmaHH Jul 5 '16 at 13:12
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I49 r49 inp49 PWL REPEAT FOREVER( 0.200 9.36 0.201 5.62 0.399 5.62 0.400 9.36 2.200 9.36 ) ENDREPEAT

When you repeat this sequence, you end up with points at (0.4, 9.36), (2.2, 9.36), and then (2.4, 9.36) (from the repetition of (0.2, 9.36)). Since these 3 points are co-linear, you can remove the middle one without changing the piecewise linear relationship.

The program is probably just doing that to reduce the complexity of calculating the points during the simulation.

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