Which: Matlab, Mathematica, Mathcad

[James Meyer]

Clients are starting to shovel data at me in
Matlab/Mathematica/Mathcad formats.

Can some regular users guide me in choosing which to purchase?

Thanks!

...Jim Thompson

I would look at the possibility of getting new clients. Those formats
you reported the present ones using lead me to believe they are too stupid or
lazy to present you with proper data.

If it won't fit an Excel spreadsheet, it ain't real data.

Jim "the other one" Meyer

 

[Jim Thompson]

I would look at the possibility of getting new clients. Those formats
you reported the present ones using lead me to believe they are too stupid or
lazy to present you with proper data.

If it won't fit an Excel spreadsheet, it ain't real data.

Jim "the other one" Meyer

But I prefer the clients with money ;-)

...Jim Thompson

 

[Rich Webb]

Clients are starting to shovel data at me in
Matlab/Mathematica/Mathcad formats.

Can some regular users guide me in choosing which to purchase?

Mathcad is a wonderful program. Very easy and intuitive to set up live
formulas and solve blocks that look like a technical report. Very handy
when you go back to something six months (or years) later. Strongly
recommended for numerical applications and it also includes some
symbolic capability.

That said, IMHO they totally screwed the individual purchaser [*] with
their current system-locked licensing scheme. Versions from 11 and later
require the dreaded "product activation" where you send them a hardware
identifier and they send you an activation key.

I've owned and upgraded a personal copy of Mathcad since the days when
it ran on DOS with a Hercules graphics card and I'll stick with my
version 2001i, thank you very much, that only requires CD-keyed
validation after installation.

[*] The enterprise versions don't require product activation but they're
insanely priced.

 

[Joerg]

Hello Jim (both),

Yes, it is amazing what you can do with Excel or MS-Works. I have even
done pretty complicated beam profile studies for ultrasound transducers
with these rather mundane pieces of software. They don't allow fancy
formulas but you can nest stuff to your heart's desire. So far I have
never hit a hard limit where I would have to concede.

But I prefer the clients with money ;-)

Then you may be forced to buy whatever software can read the files. It's
the same as with schematic capture, nothing is compatible. Maybe the
vendors just want it that way. EDIF? Forget it, I have never really seen
compatibility and it may be the same with math packages.

Regards, Joerg

 

[John Larkin]

But I prefer the clients with money ;-)

That's a hell of an attitude!

John

 

[John Larkin]

[*] The enterprise versions don't require product activation but they're
insanely priced.

Well, the starship guys can afford it.

John

 

[Jim Thompson]

That's a hell of an attitude!

John

The American WAY!

...Jim Thompson

 

[Rich Webb]

[*] The enterprise versions don't require product activation but they're
insanely priced.

Well, the starship guys can afford it.

You BASTARD! Not even a smiley with that. Now I've got to clean the
sprayed tea from the monitor and coax down a cat that hid on top of the
curtains for safety after the "explosion."

 

[Kevin Aylward]

That's a hell of an attitude!

?

Its the realistic one.

Kevin Aylward
[email protected]
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

 

[rex]

?

Its the realistic one.

Kevin Aylward

Kevin, you are so restrained these days. Got better things to do, or
just mellowing out?

 

[John Larkin]

[*] The enterprise versions don't require product activation but they're
insanely priced.

Well, the starship guys can afford it.

You BASTARD! Not even a smiley with that. Now I've got to clean the
sprayed tea from the monitor and coax down a cat that hid on top of the
curtains for safety after the "explosion."

Apologies to the cat.

John

 

[qrk]

Clients are starting to shovel data at me in
Matlab/Mathematica/Mathcad formats.

Can some regular users guide me in choosing which to purchase?

Thanks!

...Jim Thompson

If your forced into MathCad, avoid version 12 like the plague. Version
12 is supposed to have a new core and they haven't fixed bugs and made
it fully compatible with files created in previous versions. I think
version 11 is the last best version except for the bloody license
manager crap. Mathcad is easy to use and almost intuitive except for
the GUI (editing). It is easy to crash without it doing any
computations (based on versions 8 and earlier). Mathcad sucks if you
need to do decision loops and branches.

The image processing guys at my former firm really like MatLab. A bit
harder to learn, but much more capable.

 

[Jim Thompson]

If your forced into MathCad, avoid version 12 like the plague. Version
12 is supposed to have a new core and they haven't fixed bugs and made
it fully compatible with files created in previous versions. I think
version 11 is the last best version except for the bloody license
manager crap. Mathcad is easy to use and almost intuitive except for
the GUI (editing). It is easy to crash without it doing any
computations (based on versions 8 and earlier). Mathcad sucks if you
need to do decision loops and branches.

The image processing guys at my former firm really like MatLab. A bit
harder to learn, but much more capable.

Hi Mark, MatLab is what my client is pushing me to get. But an awful
lot of money for so little usage, almost as expensive as a PSpice
maintenance renewal :-(

...Jim Thompson

 

[Terry Given]

Clients are starting to shovel data at me in
Matlab/Mathematica/Mathcad formats.

Can some regular users guide me in choosing which to purchase?

Thanks!

...Jim Thompson

Hi Jim,

I have been using Mathcad since 1992, and matlab since 1990. I do the
bulk of my work in MathCAD, basically because it can be fully
self-documenting, as mentioned by others. Like any package, the user
interface is a pig when you are unfamiliar with it, but its dead easy
with practice (equation editing can be explained in about 2 minutes).
Mathcad has IME always had one *major* problem - it crashes. And there
is no auto-save function. I havent used anything past Mathcad2000, nor
do I intend to. symbolic calculations, large datasets, tricky graphs
etc. can be a problem.


For real computing I use matlab. Expensive, but worth it. it allows
serious brute force to solve problems eg series/parallel resistor value
optimisation - done by calculating every possible combination using list
of available (IOW production) parts, then sorting in order of best fit
for each of 4 different topologies. Sure, it takes a few hundred million
calculations, but thats only a few seconds after hitting enter.

matlab has seriously cool tollboxes too. FEMLAB looks promising
(although the version I tried kept eating RAM, and wouldnt mesh the
halbach array) for multi-physics FEA too.

Cheers
Terry

 

[Rich Webb]

Also "Scilab". There is a newsgroup for Scilab, comp.soft-sys.math.scilab

There are several programs in the "nearly Matlab compatible" group.

http://www.sciviews.org/benchmark/ has brief reviews of some of the
better known ones, along with benchmarks. Note that most (all?) of the
applications have later versions than the ones reviewed but it provides
a good snapshot of the state of the art as of late 2003.

O-Matrix (not free but not expensive) had better scores on some
benchmarks in its "Matlab compatible mode" than Matlab itself had. Might
be worth evaluating.

#disclaimer: I've purchased O-Matrix and also have Scilab and Octave but
almost always reach for Mathcad first.

 

[Joel Kolstad]

Terry,

I havent used anything past Mathcad2000, nor
do I intend to.

I'm a little embarassed to admit it, but one of the reasons I upgraded to
MathCAD 12 was due to their addition of dual axes on graphs... I always did
miss that in MathCAD 2000!

The product activation feature is a PITA, however. The "major" new feature in
MathCAD 12 -- using XML as the native file format -- is not something I
particularly care about, but for those (seemingly rare) "enterprise users" I
could see as being valuable.

MatLab release 14 has a lot of nice small additions from release 12 (I never
had13), such as the ability to TRACE A GRAPH. This is a feature that I think
every other major math package has had for at least 5 years if not a decade
now, so it's good to see MatLab finally catching up.

For real computing I use matlab. Expensive, but worth it. it allows
serious brute force to solve problems eg series/parallel resistor value
optimisation - done by calculating every possible combination using list
of available (IOW production) parts, then sorting in order of best fit
for each of 4 different topologies.

Ha ha... I did something similar (but simpler) than that... finding pairs of
standard 5% value components to get as close as possible to an "ideal"
value -- the idea being that the circuit needed tuning away, so why pay for 1%
parts?

---Joel

 

[Stuart Brorson]

: Hi Mark, MatLab is what my client is pushing me to get. But an awful
: lot of money for so little usage, almost as expensive as a PSpice
: maintenance renewal :-(

I second the motion to try Scilab:

http://scilabsoft.inria.fr/

I use it all the time. Open-source, freely available for download,
both Linux and Windoze versions. . . why haven't you tried it
out already?

As far as Matlab compatability: Scilab, Octave, et al. are based
(somehow) upon Linpack, the linear algebra library originally written
in Fortran. Therefore, the syntax for handling matricies and doing
math is basically identical. However, each package has its own
functions for plotting. Therefore, a graph-intensive program will
require some translation. But if your clients are just doing math
with MATLAB, then you won't need to do much work to translate their
files.

Stuart

 

[Terry Given]

Terry,




I'm a little embarassed to admit it, but one of the reasons I upgraded to
MathCAD 12 was due to their addition of dual axes on graphs... I always did
miss that in MathCAD 2000!

The product activation feature is a PITA, however. The "major" new feature in
MathCAD 12 -- using XML as the native file format -- is not something I
particularly care about, but for those (seemingly rare) "enterprise users" I
could see as being valuable.

MatLab release 14 has a lot of nice small additions from release 12 (I never
had13), such as the ability to TRACE A GRAPH. This is a feature that I think
every other major math package has had for at least 5 years if not a decade
now, so it's good to see MatLab finally catching up.




Ha ha... I did something similar (but simpler) than that... finding pairs of
standard 5% value components to get as close as possible to an "ideal"
value -- the idea being that the circuit needed tuning away, so why pay for 1%
parts?

---Joel

smt engineering often involves minimising the number of different bits.

beware of the often seriously screwy distribution of resistors etc -
anything that is tested and binned according to actual value will, of
course, have holes in the middle of the distribution. expect a +/- 1%
hole in the center of your +/- 5% distribution. likewise a hole in the
middle of the 1%.....depends entirely on the product mfg process of course.

another thing to look at is tempco. a -20 to +80C swing across a 200ppm
part is a 2% change.

by the time you factor in placement cost (often as much as the smt part
itself), the differential price between 1% 50ppm and 5% parts is bugger
all, and is insignificant unless the production volumes are staggeringly
high.

Cheers
Terry

 

[Spehro Pefhany]

smt engineering often involves minimising the number of different bits.

beware of the often seriously screwy distribution of resistors etc -
anything that is tested and binned according to actual value will, of
course, have holes in the middle of the distribution. expect a +/- 1%
hole in the center of your +/- 5% distribution. likewise a hole in the
middle of the 1%.....depends entirely on the product mfg process of course.

They don't generally test and bin resistors, they trim each of them
individually to very close to the correct value (typically within 1%
for 5% parts, from those I've checked). With leaded parts there were
vibratory feeding bowls and an instrument with thumbwheel switches
that ended the "cutting" when the set value was reached. Before the
leads and end caps were attached, IIRC. SMT parts use laser
techniques, AFAUI.

another thing to look at is tempco. a -20 to +80C swing across a 200ppm
part is a 2% change.

But where could you find an actual 200ppm SMT resistor?

by the time you factor in placement cost (often as much as the smt part
itself), the differential price between 1% 50ppm and 5% parts is bugger
all, and is insignificant unless the production volumes are staggeringly
high.

Mostly because the materials used in modern 5% chip resistors are as
good as the semi-precision ones of which you speak.

And the semi-precision 1% parts may be unsuitable or marginal for use
in precision circuits, so be careful of the specs. "1%" doesn't
necessarily mean "precision" (stability, tempco etc.)


Best regards,
Spehro Pefhany

 

[Pooh Bear]

Clients are starting to shovel data at me in
Matlab/Mathematica/Mathcad formats.

Can some regular users guide me in choosing which to purchase?

As has been observed, you may be stuck with proprietary data formats for
each.

Can your client not arrange a 'site license' or similar for you ?

FWIW I've used Mathcad since its DOS days. Started on v 2 IIRC.

I've heard nice things about Matlab - mainly from educational sources.

Personally I find Mathcad a total breeze to use. I'm not solving
anything too stunning though.

Graham