Stream, compress or keep simulation results in files

Choose the result-storage mode

1. Open a saved source netlist and Run settings. Keep Serial execution for streamed output.
2. Choose Keep interactive plots when you need retained waveform arrays, Files only — buffered for native files without retained arrays, or Files only — streamed text for queued CSV/DAT output.
3. For a file-only route, provide an explicit native output destination and .PRINT selectors for every case. Streamed text supports CSV/DAT, optionally gzip, and excludes transient measurements. Save and preview the actual plan before running.
4. After success, open a committed numerical file to plot file-only results. A planned destination or an old file does not prove that the new run completed.

Save output_rc.cir

* RC output example: 50 ohm, 0.2 pF, 10 ps time constant
V1 IN 0 PWL(0 0 10p 0 20p 1m 100p 1m)
R1 IN OUT 50
C1 OUT 0 0.2p
.OPTION ANALYSIS=VOLTAGE INTEGRATION=BDF SEED=321
.TRAN 0.5p 100p 0 0.5p
.PRINT V(IN) V(OUT) I(R1)
.END

Run buffered, streamed and compressed variants

The compressed.csv request writes compressed.csv.gz. A .gz suffix is a compression suffix; the preceding .csv or .dat selects the logical text format. Read the actual reported path.

Use buffered output when a downstream reader requires BIN or RAW. Streamed RAW falls back to CSV with a warning in the checked candidate. Compression is not applied to BIN, RAW or STDOUT.

josim-pro-cli -P 17 -o buffered.csv output_rc.cir
josim-pro-cli --stream -P 17 -o streamed.csv output_rc.cir
josim-pro-cli --compressed -P 17 -o compressed.csv output_rc.cir
josim-pro-cli --stream --compressed -P 17 -o streamed-compressed.csv.gz output_rc.cir

Check numerical data inside gzip

The checked RC outputs contain time in seconds, V(IN)/V(OUT) in volts and I(R1) in amperes: 201 finite rows over 0–100 ps. Parsed streamed and decompressed samples exactly matched the buffered output in this example. This does not measure peak memory or prove physical accuracy.

import csv, gzip, math
with gzip.open("compressed.csv.gz", "rt", encoding="utf-8-sig", newline="") as f:
    rows = list(csv.reader(f))
values = [[float(v) for v in row] for row in rows[1:] if row]
assert len(values) == 201
assert all(len(row) == 4 and all(math.isfinite(v) for v in row) for row in values)
print(rows[0], values[0][0], values[-1][0])

Save the measurement variant as measured_output.cir

* RC output example: 50 ohm, 0.2 pF, 10 ps time constant
V1 IN 0 PWL(0 0 10p 0 20p 1m 100p 1m)
R1 IN OUT 50
C1 OUT 0 0.2p
.OPTION ANALYSIS=VOLTAGE INTEGRATION=BDF SEED=321
.TRAN 0.5p 100p 0 0.5p
.PRINT V(IN) V(OUT) I(R1)
.MEASURE TRAN peak MAX V(OUT)
.END

Recover when a measurement needs buffered output

A .MEASURE TRAN request with --stream was rejected with “buffered output is required” before replacing a pre-existing result. Remove --stream, or choose a buffered GUI mode, and rerun to a new filename. The checked buffered recovery completed with finite traces and a peak measurement.

File-only mode reduces retained waveform memory; the matrix, solver state and buffered output still use memory. Writer queue capacity is not a cap on total process memory.

josim-pro-cli -P 17 -o measured.csv measured_output.cir