I think I need a program loop to get the graph to show up correctly. Suggestions?
Quick Sound Loss.smz (132 KiB) downloaded 63 time(s).

Wrote

I think I need a program loop to get the graph to show up correctly.Suggestions?

"Why does log10 look different ?"
because you have two different formulas, thus two different results

Jean,
The second equation is off/not evaluated. Graphically log to base x and log10 display differently. Question is about graph though

Strict math seems correct to me; let's compare the values for different directivity factors at ssame distance.

we have:
to simplify things we can get rid of the absolute value; in your example all numbers are above 1, plus logarithms' arguments are <= 8 in numerator and >= 12 in denominator (4*pi*distance_greater_than_1), thus:
at same distance, log10(f(x)) is the same for every directivity factor Q
Lw(Q,1.5) loses -3dB when you double Q, but at the same time the absolute value term adds +3B -> so why values are so close (and functions overlapped in the plot)

In fact, if you go further, you can do the same for Lw:
and decimal shown in the workshet are only because different decimal places shown in the results

What might be wrong...

You have sound pressure measured by the vendor -> You have to calculate the power level for the distance and directivity condition of the vendor

Then you have the sound power level of your source... it's a constant! Use this value to estimate the sound power at various distances for various directivity conditions!


Quick Sound Loss - rev.1.sm (134 KiB) downloaded 58 time(s).

Davide,
I did the same thing, where I assumed directivity is b=2 on Lw. I'll just document that and move on as the rest of the math appears to work out

Wrote

Jean,
The second equation is off/not evaluated.Graphically log to base x and log10 display differently.Question is about graph though

Few more things you can do as real project.
Line style "splines" is a bit smoother in the low region.



Quick Sound Loss - rev.2.sm (134 KiB) downloaded 53 time(s).

Funny ...
OK, here I am as I had done most of the items that Davide and Jean added. Now I would like to add a "dot" or a vertical line where the dB.final is. Please use this sheet
Quick Sound Loss.smz (135 KiB) downloaded 57 time(s).

Jean, I did not see where you used a spline

All should I be using "cinterp" to place the "dot?

Something like this?




Quick Sound Loss - rev.1.sm (134 KiB) downloaded 51 time(s).


Best Regards

Carlos

Wrote

Jean, I did not see where you used a spline

All should I be using "cinterp" to place the "dot?

1. spline is for line style ... line/spline.
2. what that gyzma #,#,#,,,does in maths ?
3. X_Y plot does not support " in your plot suggestion
4. X_Y is for final/final/final ... project
once done, if you rework something above=> it will freak the plot
X_Y plot has slightly pregnant memory. Doctored in red .

Quick Sound Loss (3).sm (140 KiB) downloaded 63 time(s).

Wrote

Something like this?

Carlos,
I think you attached the wrong file. Yes, that is what I was looking for.

Jean,
When I double click the graph on your latest file, my computer locks up. I'm on version 0.99.6671.

NOW my file is locking up!!! ARRG

Ok, This is the right file


Quick Sound Loss (1)_r1.sm (140 KiB) downloaded 72 time(s).


Best Regards

Carlos

Wrote

Jean,
When I double click the graph on your latest file, my computer locks up.I'm on version 0.99.6671.

My 6179 opens your 6671 ... your 6671 freezes opening 6179
Is it a bug ?
BTW, attach an image of the polynomials that fail [as you reported].

Wrote

Few more things you can do as real project.

Thanks Elsid,
Nice project, saved for myself, you can have it as is.

Jean



Inst_dB Sound.sm (142 KiB) downloaded 53 time(s).

Well, Here we go again ...
I found a quirk. Depending on values dB initial values, neither solve nor FindRoot is functional. I was plugging in values by hand without seeing an issue. I tried a "higher" dB set of values (86 vs 75) for equipment and the calculation *zap*
Quick Sound Loss.smz (168 KiB) downloaded 55 time(s).
Also, the X-Y plot legend information *ZAP*

Wrote

Well, Here we go again ...
I found a quirk.Depending on values dB initial values, neither solve nor FindRoot is functional.I was plugging in values by hand without seeing an issue.I tried a "higher" dB set of values (86 vs 75) for equipment and the calculation *zap*

That one was Doctored and you don't use the Doctored version.
Explained before, if above X_Y something is Doctored, zap.

Quick Sound Loss (4) Doctored 20180413.sm (167 KiB) downloaded 57 time(s).

Found the issue(s). See revamped file. Still having issues in that X-Y plot Labels for the legend *zap*Quick Sound Loss.smz (142 KiB) downloaded 92 time(s).
Edit: Two bugs

1. X-Y Plot. If functions crash, *Zap* to the legend titles. All other titles OK. Legend is empty due to laziness after last 5 crashes
   
2. solve(4) did not like trying to cancel units in the denominator of the final function (#dist). As I was adding units to x:0-100 FT and dividing the units meters in the function, the function crashed in the solve block (Just the function, with all values plugged in except for x = vector, so it's a solve(4) issue).

This is one of those sheets where UNITS are huge! The equations are all based off of SI/metric references. Major issue

There is additional documentation and function definition updates. Sanity check the graph x scale (adjusted for feet since I'm in the US). Should be good now

Wrote

Found the issue.I'll post revamp file.Still having issues in that X-Y plot Labels for the legend *zap*

Clik on "list", edit "series name".

Revisiting this old calc with SMath newer features and some function definitions.

1. No longer works if I redefine the logarithmic sum with vectorize
   
2. I cannot get the "heat capacity function" to work for ploting

Sound Loss (Quick).sm (476 KiB) downloaded 39 time(s).
Thanks for the help.

Hi. Some notes, but I'm not sure if this solve all of the issues:
1. Use count inside rangeindividual, but not outside. You use it in f(x, b ), and guess that could be problematic.
2. After that, you divide x by 'm in f and x by feet in rangeindividual, choose only one.
3. Maybe here don't affect, but if rangeindividual have not f(#,#) as parameter, define f before rangeindividual, you know, just in case.



Best regards.
Alvaro.