Cancel
Showing results for 
Search instead for 
Did you mean: 

How to pick the n-th peak on the curve (that is, put the Y-cursor on the n-th peak)?

Creator
Creator

There are normally some x-intersections showing alone the cursor, but very difficult to control. Is there an easier way to find the value of n-th peak from the curve without doing a peak-valley cycle counting and ranking the peaks to find out?

find peaks.jpg

 

4 REPLIES

Re: How to pick the n-th peak on the curve (that is, put the Y-cursor on the n-th peak)?

Siemens Legend Siemens Legend
Siemens Legend

Hi

 

Not sure, but maybe the following would work for you?  It does not use a Y cursor:

 

First select the curve in the display, and use the conditioning toolbar to multiply by 1.  Click on the * symbol:

 

peak1.png

 

 

This stores the data into the project, and allows an automatic peak cursor to be used.

 

Right click in the display (hold down CONTROL key while right clicking if needed), and select “Add automatic cursor -> Peak”

 

peak2.png

 

 

Then to get to the n-th peak, right click on the cursor and select “Automatic Peak Parameters”

 

peak3.png

 

 

In the “Automatic peak parameters” dialog box, set the “Max number of extrema” to desired number of peaks (in this example 10).  Press Ok when done.

 

peak4.png

 

 

10 cursors will be put on display for 10 highest peaks.  To get them into Excel, right click in display (holding CONTROL if need be) and choose “Cursor Legend -> Auto”.

 

peak5.png

 

 

Right click on new legend and choose “Copy” and then paste values into Excel.

 

peak6.png

 

 

Note, if the cursor calculations do not work, there may be a limit on the number of data points to be used for the peak parameter detection.  The default number of data points can be increased under “Tools -> Options -> Data”.  Set the ‘max number of samples’ numbers higher (maybe add three zeros).

 

peak7.png

 

 

 

Re: How to pick the n-th peak on the curve (that is, put the Y-cursor on the n-th peak)?

Creator
Creator

Thanks! I tried and it worked! 

By the way, why couldn't I use the auto peak cursor directly on the (unsupported) throughput data? 

Re: How to pick the n-th peak on the curve (that is, put the Y-cursor on the n-th peak)?

Siemens Phenom Siemens Phenom
Siemens Phenom

Hello Z_L,

 

Unfortunately the decision was made to only use "block" data with the Automatic Peak and Valley cursors.  To convert throughput data to a block, you can display it, select it and use the Conditioning toolbar to multiple or divide by one as PJS suggested.  This will convert it to a block and store it in a Conditioning folder within the active Section.

 

Also as Pete suggested, when we display throughput data if it is more than a million samples (by default) we show an overview of the data and not every data point is displayed.  The automatic peak cursor (and the Double X cursor calculations, Legend Calculated Content calculations, etc.) will not work with more than a million data samples so under Tools, Options, Data you need to change the max number of data samples that can be displayed.  For this reason, and a few others, it was decided not to have the automatic peak and valley cursors work with throughput data - hence the workaround.

 

When the throughput is less than the max number of samples under Tools, Options Data the icon will blue and when it is more than that it will be half blue and half red as shown here.    That is a hint that the automatic cursors, the calculated content in the legend, the double X cursor calculations, etc. will not work on the full data set.

 

3-29-2018 9-51-38 AM.jpg

 

Kevin

Re: How to pick the n-th peak on the curve (that is, put the Y-cursor on the n-th peak)?

Siemens Legend Siemens Legend
Siemens Legend

Hi Z_L,

 

Glad this worked, and hopefully Kevin's reply explains the cursor and throughput data.

 

If you can, please mark "Accept as Solution" to help guide other users in the forum who may have the same question.

 

Thanks