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.STEP log file issue

Thread Summary

The user reported that in LTspice, the .step parameter values in the log file were being rounded to 6 digits, causing issues with scripting tools like PyLTSpice. The issue was fixed in LTspice 24.0.9, with full precision values now reported, though the order of steps and some report parameters changed. In LTspice 24.1.3, the .step command generated 12 steps instead of 11 due to binary floating-point precision, but this was improved in 24.1.10, with only the last step being unnecessarily repeated.
AI Generated Content
Category: Software
Product Number: LTSpice
Software Version: 17.1.11

Hello,

When I run following netlist:

* test1.net: Test of .step
R1 N001 0 1k
V1 N001 0 {volt}
.step param volt 100 100.001 .1m
.tran 1
.meas tran volt2 param volt
.options numdgt = 15
.options measdgt = 15
.end

the steps in log are rounded to 6 digits:

Circuit: * test1.net: Test of .step

Direct Newton iteration for .op point succeeded.
.step volt=100
.step volt=100
.step volt=100
.step volt=100
.step volt=100
.step volt=100.001
.step volt=100.001
.step volt=100.001
.step volt=100.001
.step volt=100.001
.step volt=100.001


Measurement: volt2
  step    volt
     1    100
     2    100.0001
     3    100.0002
     4    100.0003
     5    100.0004
     6    100.0005
     7    100.0006
     8    100.0007
     9    100.0008
    10    100.0009
    11    100.001


Date: Tue Oct 24 08:17:24 2023
Total elapsed time: 0.601 seconds.

tnom = 27
temp = 27
method = modified trap
totiter = 2091
traniter = 2088
tranpoints = 1045
accept = 1045
rejected = 0
matrix size = 2
fillins = 0
solver = Normal
Avg thread counts: 4.5/8.1/8.1/4.5
Matrix Compiler1: off  [0.0]/0.0/0.0
Matrix Compiler2: off  [0.0]/0.0/0.0
 

Simulation, measurements works properly but this logfile data. There is a workaround but it is a big inconvenience especially when using scripting, like PyLTSpice which relies on the log file.

Is it normal? Can it be changed by settings? Or if not, will it be fixed?

Best regards,

pavo