I have a (long) list of spectral data. It consists of 1 column of time
increments, and 1 column of intensity values. I am trying to find the maximum
for each of three peaks in the data, plus, once the maximum has been found,
the values closest to halfway between the baseline and maximum intensity.
This will be 4 values; two on either side of the peak bracketing the halfway
point. I can use VLOOKUP or INDEX and MATCH to find these values on one side
of the maximum, but cannot figure out how to tell Excel to look on the other
side of maximum, especially for multiple peaks. Any help here would be
greatly appreciated.

If seeing the data would be helpful, I am willing to use email correspondence.

"davis-wsu" wrote:

I have a (long) list of spectral data. It consists of 1 column of time
increments, and 1 column of intensity values. I am trying to find the maximum
for each of three peaks in the data, plus, once the maximum has been found,
the values closest to halfway between the baseline and maximum intensity.
This will be 4 values; two on either side of the peak bracketing the halfway
point. I can use VLOOKUP or INDEX and MATCH to find these values on one side
of the maximum, but cannot figure out how to tell Excel to look on the other
side of maximum, especially for multiple peaks. Any help here would be
greatly appreciated.

Xray spectrometry?

Let me know how to contact you.

--
Biff
Microsoft Excel MVP


"davis-wsu" wrote in message
...
If seeing the data would be helpful, I am willing to use email
correspondence.

"davis-wsu" wrote:

I have a (long) list of spectral data. It consists of 1 column of time
increments, and 1 column of intensity values. I am trying to find the
maximum
for each of three peaks in the data, plus, once the maximum has been
found,
the values closest to halfway between the baseline and maximum intensity.
This will be 4 values; two on either side of the peak bracketing the
halfway
point. I can use VLOOKUP or INDEX and MATCH to find these values on one
side
of the maximum, but cannot figure out how to tell Excel to look on the
other
side of maximum, especially for multiple peaks. Any help here would be
greatly appreciated.

I can be reached at
It is actually ion mobility spectrometry

"T. Valko" wrote:

Xray spectrometry?

Let me know how to contact you.

--
Biff
Microsoft Excel MVP


"davis-wsu" wrote in message
...
If seeing the data would be helpful, I am willing to use email
correspondence.

"davis-wsu" wrote:

I have a (long) list of spectral data. It consists of 1 column of time
increments, and 1 column of intensity values. I am trying to find the
maximum
for each of three peaks in the data, plus, once the maximum has been
found,
the values closest to halfway between the baseline and maximum intensity.
This will be 4 values; two on either side of the peak bracketing the
halfway
point. I can use VLOOKUP or INDEX and MATCH to find these values on one
side
of the maximum, but cannot figure out how to tell Excel to look on the
other
side of maximum, especially for multiple peaks. Any help here would be
greatly appreciated.