Scale Type
Two types of chart Scaling can be selected: Linear or Semi-Log.
Contents
Linear Scaling
A Linear price scale is the conventional, absolute scale. A $10 change in price will always be represented by the same displacement along the vertical axis, regardless of the base price from which the change took place.
Setting Linear Scaling Type
Scaling Type is set from the Format Instruments window:
- Open the Format Instruments window.
To open the Format Instruments window, click the Format Instruments
icon on the main toolbar;
if the Format Objects window appears, select the symbol and click the Format button.
The Format Instruments window can also be opened by one of the following methods:
- Position the mouse pointer over the symbol's data series; double-click once the Pointer
changes into a Hand 
;
- Position the mouse pointer over the symbol's data series; once the Pointer changes into a Hand right-click and then click Format Symbol Name;
- Right-click on an empty area of the chart and then click Format Instruments; if the Format Objects window appears, select the symbol and click the Format button;
- Select Format in the main menu and click Instrument; if the Format Objects window appears, select the symbol and click the Format button. - Select the Scaling tab.
- In the Scaling Type section, click the Linear radio button.
To center the last quote in the middle of the price scale, check the Center Last Price check box; the last quote can not be centered for a chart with a User Defined price scale.
To use these scaling settings for all new charts, check Use as Default check box.
Semi-Log Scaling
A Semi-Log (percent-of-change) price scale is a percentage-based scale. A 10% change in price will always be represented by the same displacement along the vertical axis, regardless of the absolute price change. A $5 price change from a $50 base price (10%) will be represented by the exact same vertical displacement as a $10 price change from a $100 base price (10%), even though the absolute values of $5 and $10 are not equal.
Setting Semi-Log Scaling Type
Scaling Type is set from the Format Instruments window:
- Open the Format Instruments window.
To open the Format Instruments window, click the Format Instruments icon on the main toolbar;
if the Format Objects window appears, select the symbol and click the Format button.
The Format Instruments window can also be opened by one of the following methods:
- Position the mouse pointer over the symbol's data series; double-click once the Pointer changes into a Hand ;
- Position the mouse pointer over the symbol's data series; once the Pointer changes into a Hand right-click and then click Format Symbol Name;
- Right-click on an empty area of the chart and then click Format Instruments; if the Format Objects window appears, select the symbol and click the Format button;
- Select Format in the main menu and click Instrument; if the Format Objects window appears, select the symbol and click the Format button. - Select the Scaling tab.
- In the Scaling Type section, click the Semi-Log radio button.
To center the last quote in the middle of the price scale, check the Center Last Price check box; the last quote can not be centered for a chart with a User Defined price scale.
To use these scaling settings for all new charts, check Use as Default check box.
