SCALING [ACTIVE CHANNEL] This submenu has five items:
HIGH RESOLUTION
Automatically finds the Y-range of the data and selects Y-axis scaling
equal to the total range plus 5% in either direction.
SCALE TO INCLUDE ZERO
Selects a range that includes zero and the entire
Y-range of data, and sets the tic marks at whole numbers or simple fractions.
If the data are all positive or all negative, the scale will be set to
include at least 110% of the data range, using zero as the minimum or maximum
Y value, respectively.
- If data include both positive and negative values, this is equivalent
to 'NORMAL SCALING'.
NORMAL SCALING
LabAnalyst's
default scaling protocol. Selects a Y-axis scaling factor that includes
the entire Y-range of the data, with tic marks set at whole numbers or
simple fractions. If data include both positive and negative values,
this is equal to 'SCALE TO ZERO'. If data are all positive
or all negative, 'NORMAL SCALING' may select a smaller scale factor
(i.e., higher resolution).
MANUAL SCALING...
Allows manual selection of minimum and maximum
Y-values for the plot area. This is useful to optimize scaling for
plot regions of particular interest. On may occasions, the automatic
scaling options (NORMAL SCALING and SCALE TO ZERO) do not
show areas of particular interest at sufficiently high resolution.
When the manual scaling window (shown at right) opens, it displays the
current scaling values for the active channel. You can modify them
as desired.
SET INTERACTIVELY... Lets
you use the mouse and cursor in the plot area to set the scaling limits,
using this small window:
- Click the 'Upper limit' or 'Lower limit'
button, then move the cursor line to the desired spot and click the mouse
once. You can also expand a plot with a too-confining scale by clicking
the 'Expand 2X' or 'Expand 3X' buttons. When done,
click the 'done' or 'cancel' buttons. Clicking the
plot area when the horizontal cursor line is not showing is the
same as clicking the 'done' button.
When using manual or interactive scaling, it's
important to remember that the SAME scaling constraints will apply to all
segments of the channel -- regardless of what data they contain.
Manual scaling is switched off (and Normal
scaling is switched on) whenever a new file is loaded. |
When you
perform a baseline correction on a manually-scaled channel (either 'regular'
manual scaling or interactive scaling), scaling is automatically
reset to 'HIGH RESOLUTION' mode. This is because the baseline
operation changes the position of the data, so manually-set limits are
frequently completely outside the data range after baseline correction. |
SCALING [ALL CHANNELS] This has a submenu with three items:
HIGH RESOLUTION SCALE TO INCLUDE ZERO NORMAL SCALING
⌘N These have the same action as described above,
except that they reset the scaling defaults for all channels (not
just the active channel).
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