peterfeicht / ltspice2matlab Goto Github PK

For a binary DC Sweep (.dc) simulation from LTspice XVII, steps are not recognized properly.
The text import uses different logic than the binary import for recognizing steps in Transient Analysis (.tran) and DC Sweep (.dc), maybe I forgot to make a change to both. I think the text logic should work for binary too, at least in the DC Sweep (.dc) case.

When adding support for UTF-16 encoded LTspice XVII files I completely forgot about non-binary files, which would encode the data as UTF-16 as well. This is not supported right now and should be added.

Note: MATLAB's fopen function doesn't support UTF-16 officially, though it has been reported to work nonetheless.

Issue seems to appear only when Pseudo Transient is used for finding the operating point, and is consistent when I use .option commands 'noopiter', 'gminsteps = 0' and 'itl6 = 0' in my simulation. The function is consistently getting stuck in the loop around line 502 and does not leave it even after few hours (as I left it running overnight).

Recent updated function has unidentified variable or function "tolower"
Actually it should be "lower"

The attached .raw file contains four steps of a DC Sweep (.dc) simulation from two separate .step commands. The number of data points is not divisible by 4, because in some of the steps the last source value is missing.

I have no idea why LTspice would save the data this way, but we should try to handle this case nonetheless. I also don't know whether this can occur for Transient (.tran) simulations, but the handling is the same in any case.

Hello,

I am able to load the .raw file when I run a basic .tran command. However, when I include a .step directive in the simulation I get the following error from MATLAB:

Error using reshape
Size arguments must be real integers.

Error in LTspice2Matlab (line 531)
raw_data.variable_mat = reshape(raw_data.variable_mat, mat_size(1), mat_size(2) / num_steps, num_steps);

Error in test (line 6)
sr = LTspice2Matlab(path);

Any help would be greatley appreciated.

Thank You,

Ethan

Currently the "double" flag is not recognized. This flag signifies that all data is double precision (The LTspice default is that for .TRAN time is float64 and all other data is float32). This format can occur when numdgt is set above 8, however, it also is seen for NGSPICE raw files.
I've added a diff that recognizes 'double'. (Note that there can be problems when the data is not from a .TRAN simulation.)

The same diff also shows a modification for when selected_vars is a string when calling LTspice2Matlab. In that case the program directly returns the data for the indicated trace. The old behavior is that selected_vars returns the index needed to retrieve the data for the trace but not the data itself. Currently it only works for one trace.

I attached the modified MATLAB file just for convenience.

-marcel
lt2m.txt
LTspice2Matlab.txt

Hello, I am moving from MATLAB to Octave and I would like to know please how can I use this same script but in Octave without it having to crash because the MTLAB function 'contains' is not defined in Octave?

Thanks in advance.

Wallflower

Gentlemen,
after update to the original code of ltspice2matlab it stopped working in Octave 4.0.0.
I fixed it on my local PC, I had to revert to the old-fashioned style of string look-up.
Also newline constant has not been recognized by Octave. I would like to send you the updated code for tests.