SwitcherCad Q

I have done something like that a few times. I would start with a small program to move a viewing window over the data, showing hex and ascii, and try to interprete the first set of bytes of the block as short/int/long/float/double, using little and big endian. And then use my brain as a pattern recognition system. Move the block 1,2,4,8,16 or N bytes at a time, to recognize block structures. If you are lucky and there is reasonable data structure in there, you might succeed.

Reply to
Sjouke Burry
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I have this small .RAW file (over 1Gbyte) and i want to do an X-Y plot of two parameters. Reading this file is fairly easy and fast, but i do not know the formatting - so i do not know how to pick out a given dataset, like V(n017) and V(n002). How can this be done?

Reply to
Robert Baer

On Nov 2, 7:27 am, Robert Baer

The file *should* start with a decent header including a description of the format used to encode the data. Why not post the first few Kb here to attempt to reverse its format ?

Reply to
John

Are the files in the default binary format, or have you checked the "ASCII Data Files" box?

I import ASCII rawfiles into Berkeley Spice 3f4 (a few LTSpice-specific lines at the head of the file need getting rid of), and do polar plots from there.

There's an m-file for importing spice rawfiles into Matlab. Won't run in octave, even with the --braindead command line option.

There's another for octave, but it doesn't seem to parse LTSpice rawfiles properly. Tells me there are 0 variables and 0 points. Still playing with it.

--
"For a successful technology, reality must take precedence 
over public relations, for nature cannot be fooled."
                                       (Richard Feynman)
Reply to
Fred Abse

I don't think you're going to have much luck trying to interpret the RAW data file format. From the manual at

formatting link
/scad3.pdf:

LTspice compresses the raw data files as they are generated. A compressed file can be 50 times smaller than the un-compressed one. This is a lossy compression. This pane of the control panel allows you to control how lossy the compression runs.

-- Marc

Y
Reply to
Marc Guardiani

On Nov 2, 9:21=A0pm, Marc Guardiani

Then set the compression ratio to zero % to get a uncompressed RAW file - will this work ?

Reply to
John

"Robert Baer" schrieb im Newsbeitrag news:B_-dna5Oycu-PFLRnZ2dnUVZ snipped-for-privacy@posted.localnet...

Hello Robert,

If you have the waveform window active, you can simply do an export of waveforms.

File -> Export

A dialog window will pop-up. Select the waveforms you want to export.

If you already have the raw-file and want open it again, just drag it into LTspice from the Windows explorer.window.

Best regards, Helmut

Reply to
Helmut Sennewald

If you have access to Matlab you can use the LTspice2Matlab m file to import a LTspice raw file into Matlab. See:

formatting link

Howard

Reply to
hrh1818

The files are created by switcherCad; draw any schematic (that will run) and save. Look at the .RAW file; the header has no info concerning the format or coding. The only "clues" are the names (and count) of the nodes, possible order of values per node, and terminated by "Binary:" (no quotes).

Reply to
Robert Baer

That is a thought; i did default mode (ascii header, binary data). Will see if i can try the ASCII format; file will prolly by 8 to 16 times larger or roughly(?) 32Gbytes if the OS allows such a size (forgot).

Reply to
Robert Baer

formatting link

Holy S!!!!!!!! FIFTY times?? That is maybe 100Gbytes uncompressed! Even if the OS would allow a filesize like that, i would need to get a terror-bite HD to chomp on!

Reply to
Robert Baer

formatting link

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The requested URL /software/scad3.pdf: was not found on this server.

Reply to
Robert Baer

If it is settable at all, a factor of ONE is the logical value; division by zero is NAN. BTW, i have seen some NaN in the binary..

Reply to
Robert Baer

Will try, but it is not the waveform, it is the data stream of one node VS another note i want to plot.

Reply to
Robert Baer

formatting link

Heh... He said 'suc-seed!'

The RNG in NetHack is better than that!

You guys are seedy characters!

I am The WallRus! King of ArmageTRON Advanced!

Reply to
WallyWallWhackr

Additive or subtractive? (same as the termination resistance question).

Reply to
My Name Is Tzu How Do You Do

Robert,

Yuu will get a text file with three columns. Then use any other plot program to plot the second column versus the third column. Isn't that what you wanted to plot.

You can do an x-y plot in LTspice too. Simply chnage the x-axis to V(node2).

If you want a smaller data file, you can limit the saved data to only those two nodes with a SPICE-directive in your schematic.

.save V(node1) V(node2)

Best regards, Helmut.

Reply to
Helmut Sennewald

But not a polar or Smith plot. Good ol' Berkeley Spice will.

Shame that.

--
"For a successful technology, reality must take precedence 
over public relations, for nature cannot be fooled."
                                       (Richard Feynman)
Reply to
Fred Abse

I've got the octave input thing running properly with LTSpice ASCII rawfiles. Loads the variables into a matrix. An octave whizz (which I'm not) could probably do all sorts of clever things.

Only works with ASCII files, not binary.

--
"For a successful technology, reality must take precedence 
over public relations, for nature cannot be fooled."
                                       (Richard Feynman)
Reply to
Fred Abse

OOOOooohhh!! Super! Many thanks.

Reply to
Robert Baer

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