Morning all

Need to calculate time cycles, can anyone help??

Tks in advance

Well perhaps ... if you can explain what you mean in a bit more
detail.

Pete

On Dec 3, 11:28 am, Antonio wrote:
Morning all

Need to calculate time cycles, can anyone help??

Tks in advance

"Antonio" wrote in message
...
Morning all

Need to calculate time cycles, can anyone help??

Tks in advance

In Excel, dates are stored as number of days since 31st Dec 1899 (that is,
one day =1). So, for example, today (3rd Dec 2007) is 39419. Time is just
the fractional part of these numbers. 6:00am is quarter of the way through
the day, so 6:00am this morning is 39419.25. Formatting just displays these
numbers in a conventional date/time format. But once you understand the
underlying numbers, you can calculate with them as you wish. If you still
need help, please explain what you mean by "time cycles".

Hi Pete

Have two columns

1st date and 2nd temp. Need to find the temp cycles over time

Tks

"Pete_UK" wrote:

Well perhaps ... if you can explain what you mean in a bit more
detail.

Pete

On Dec 3, 11:28 am, Antonio wrote:
Morning all

Need to calculate time cycles, can anyone help??

Tks in advance

That adds nothing to your first post.

Give a worked through example and then show what your starting data will
look like.

--
---
HTH

Bob


(there's no email, no snail mail, but somewhere should be gmail in my addy)



"Antonio" wrote in message
...
Hi Pete

Have two columns

1st date and 2nd temp. Need to find the temp cycles over time

Tks

"Pete_UK" wrote:

Well perhaps ... if you can explain what you mean in a bit more
detail.

Pete

On Dec 3, 11:28 am, Antonio wrote:
Morning all

Need to calculate time cycles, can anyone help??

Tks in advance

Hi again

Pls advise a email to where to send data

Tks in advance

"Bob Phillips" wrote:

That adds nothing to your first post.

Give a worked through example and then show what your starting data will
look like.

--
---
HTH

Bob


(there's no email, no snail mail, but somewhere should be gmail in my addy)



"Antonio" wrote in message
...
Hi Pete

Have two columns

1st date and 2nd temp. Need to find the temp cycles over time

Tks

"Pete_UK" wrote:

Well perhaps ... if you can explain what you mean in a bit more
detail.

Pete

On Dec 3, 11:28 am, Antonio wrote:
Morning all

Need to calculate time cycles, can anyone help??

Tks in advance

Assume your data looks like the one posted at
http://tinyurl.com/3c8o9t
Fourier Analysis will be used to find the period of the waveform.
Cut the 2 columns to 128 row.
Only lengths of 64, 128, 256 etc are allowed.
Name the 2 columns MyTime and MyVal.
Shown here are only 4 of 128 data rows:

MyTime MyVal FFT MyPower MyPowCu MyFreq
1.00E-11 0.19
-21.7
1.00E-07 0.00 -30.5-6.5i 972.9 972.9
9.922E-08
2.00E-07 -0.19 -38.2-3.1i 1473.3 2446.2
1.984E-07
3.00E-07 -1.24 -42.5+3.5i 1820.6 4266.9 2.977E-07

Half_Area
226338
Period
1.091E-06

Tools Data Analysis Fourier Analysis
Input Range: MyVal
Output Range: FFT
If the above matrix starts at A1, enter at D3, E3 and F3 respectively
=IMABS(C3)^2
=MyPower+E2
=(ROW()-2)*(MAX(MyTime)-MIN(MyTime))/COUNTA(MyTime)
Copy them down and name the ranges as shown in the above table.
Half_Area and Period have these formulas
=INDEX(MyPowCu,COUNTA(MyVal)/2+1,)/2
=LOOKUP(Half_Area,MyPowCu,MyFreq)

Oh no, I mean lay it out in text form here.

--
---
HTH

Bob


(there's no email, no snail mail, but somewhere should be gmail in my addy)



"Antonio" wrote in message
...
Hi again

Pls advise a email to where to send data

Tks in advance

"Bob Phillips" wrote:

That adds nothing to your first post.

Give a worked through example and then show what your starting data will
look like.

--
---
HTH

Bob


(there's no email, no snail mail, but somewhere should be gmail in my
addy)



"Antonio" wrote in message
...
Hi Pete

Have two columns

1st date and 2nd temp. Need to find the temp cycles over time

Tks

"Pete_UK" wrote:

Well perhaps ... if you can explain what you mean in a bit more
detail.

Pete

On Dec 3, 11:28 am, Antonio wrote:
Morning all

Need to calculate time cycles, can anyone help??

Tks in advance