hi i have a table of values [R(t=60)=50965] with no obvious pattern and i need to create a function to fit into the formula
1/T = d (ln(R(t)) / dt
my thought was to make S(t)=ln(R(t)) and do d(S(t))/dt but i dont know how to turn a bunch of values into a function in smath and excel doesnt understand the function properly (i left out the last value and did auto complete and it was too far off)


R(t) is in counts per second
and i am solving for T

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hi i have a table of values [R(t=60)=50965] with no obvious pattern and i need to create a function to fit into the formula
1/T = d (ln(R(t)) / dt

Start by creating the Smath data table, attach in the Forum.
Your wording looks very alike fitting the laser project.
Toke > 1 month to do in Mathcad as it was so unusual.
But we had lot more data points.
Jean

HW8Q1.sm (2,45 KiB) scaricato 1164 volta(e).

do you mean like a matrix?

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Start by creating the Smath data table,

Before going ahead, the wiggling around the straight fit,
is it real or digitizing noise from equipment ?

Data.sm (28,76 KiB) scaricato 1155 volta(e).

Wrote

Wrote

Start by creating the Smath data table,

Before going ahead, the wiggling around the straight fit,
is it real or digitizing noise from equipment ?

i would be comfortable assuming it is based on the contextFile non trovato.File non trovato.

... in your original scale XY.

Data.sm (40,67 KiB) scaricato 1154 volta(e).

thank you so much
as much as i would like to say part b of the question i need to do my own homework i just couldnt understand how to get the equation of that line

thanks again

Wrote

thank you so much
as much as I would like to say part b of the question I need to do my own homework I just couldn't understand how to get the equation of that line

1. You mean equation of the straight red line of the first plot ?
2. Or: the piece wise linterp between the support points ?
linterp, cinterp, ainterp are built-in Smath from f(x) menu.
The straight line in [1] can be manipulated a bit from statistical methods [Not Smath built-in].
Also, if you don't like the rough bifurcation at the supports
points, easy to fillet for smooth path.
No more need for the first replies before the last attachment,
then will be removed.

Cheers ... Jean

I think you can also use the least-squares method to find the equation that best fits your data.



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Best Regards

Carlos

Here is Cholesky [Least Squares], otherwise.
Ge sensor [Germanium] is an exceptional application.
Jean



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