Userplot
 

Name:  userplot - set up custom plotting

Description:  userplot sets up user-defined plot expressions in multiple plotting windows

First, the user is asked whether plotting of custom output expressions is desired. If not, the value plotted during scanning reverts to raw counts in the DET counter. If custom plotting is desired, a short menu of options pops up:

Defined user expressions:

Plot          Expression                           File         Screen       Plot           Label     
number     to plot                                  output     output         window


* indicates primary expression in a given window


Options: 
        a - add expression
        r - remove expression
        c - change characteristics
        q - quit

Option (p)? 

If you wish to add an expression, choose option (a) and the screen will show:

Your userplot expression may be any combination of valid Spec
variables, arithmetic functions, motor positions, counters,
and constants.  When using motor positions or counters in an
expression, give their mnemonics.  Indicate mnemonics by
separating them from other characters with spaces.
Hit any key to continue.

After you continue the screen will show a list of the current counter configurations. You may now type in your expression separating variables from other variables with spaces.

An expression is defined using the a option. An expression may consist of any combination of variables, arithmetic functions, motor positions, and counters. To include a motor position or counter value in an expression, type the mnemonic of the motor or counter in the expression, separated from other words and characters by spaces. For example, below is an expression where the number taken from the counter flour is squared, and added to the position of the motor sampx times a variable k.

flour * flour + k * sampx

It would also have been valid to write

pow( flour, 2) + (k * sampx )

making use of the Spec function pow for raising a number to a power. See the Spec reference guide (pp. 13-14 of the Spec functions reference) for a listing of valid Spec arithmetic functions. The value of the variable k may be set from the Spec command level, or it may be an internal variable from a scan.

You will also be asked other questions:

Print this number to the screen (YES)?
Print this number to the datafile (YES)? 
Plot this expression (YES)? 
In which window (1)?
Make this the primary expression in this window (YES)?

Once the expression has been entered, the user is asked the name of the expression. The user is also asked whether the value is to be printed to the screen and/or the datafile. This choice is presented so that important values may be printed to the datafile but not allowed to clutter the screen, or so that a quick look at trends in the data can be taken without unduly enlarging the datafile. You will also be asked if you wish to plot the expression, and in which window.

You can have up to 5 windows available for plotting and can even resize them all to be visible at once. The primary expression is the one that the peak, COM, & FWHM get calculated for and sent to the data file if you choose so in setscans.

After adding 4 user-defined plots your main userplot menu will look something like this:

Defined user expressions:

Plot          Expression                           File       Screen     Plot          Label     
number     to plot                                  output    output      window

1              A_PE                                   yes        yes          2             A line posn(mm)
1              A_PE / 25.4                          yes        yes         *2            A line posn(inches)
2              B_PE / 25.4 / 12 / 6               yes        yes         *1            B line posn(fathoms)
3              C_PE / 25.4 / 12 / 3 / 220       yes        yes         *3            C line posn(furlongs)

* indicates primary expression in a given window

Options: 
        a - add expression
        r - remove expression
        c - change characteristics
        q - quit

Option (p)? 

Note that in window 2, there are 2 versions of A_PE but only the one with the * will have the Peak, COM, & FWHM calculated at the end of the scan.

Other options on the main menu include:

• r option, which deletes a single expression,

• c option, which is used to change the expression that will be plotted. Once you choose c you will be asked:

  Which expression (0)?

  and then presented with a screen similar to the following:

  Modifying the following expression:
  
  Plot        Expression                           File        Screen     Plot        Label     
  number   to plot                                  output     output      window
  
  1            A_PE / 25.4                          yes        yes          *2           A line posn (inches)
  
  * indicates primary expression in a given window
  
  Operations:
          e -- change expression
          f -- toggle file output on/off
          s -- toggle screen output on/off
          w -- change plot window
          p -- make this the primary plot in window
          l -- change label
          q -- quit (return to main menu)
  Choice (q)? 

  One common expression used in EXAFS is log ( I0 / I1 )

To disable plotting of all expressions and resume plotting the DET counter, answer 'no' to the initial question of whether you want your expression plotted.

Last Update: 2006-09-21