Logarithmic Sliders

Författare/skapare:
Jonas Hall

Introduction

Making a slider take anything but linear values involves some sort of two-step process. In this case a calculation. The slider value is exponentiated, and this new value is shown in a text box instead of the actual slider value. (This side originally created by Jonas Hall)

Sample construction

When to use

This is useful when you want to changa a variable across a great range of values:
  • If the variable represents illumination, in Lux, then typically you want this to vary from 1 Lux (dark room) to 50000 Lux (bright sunny day)
  • Similarly, if the variable represents seimic energy, luminosity, sound intensity, hydrogen ion concentration etc, then the actual slider represents the Richter scale magnitude, stellar magnitude, sound level in dB, pH-value etc.

How do you do this?

The construction above uses the following KEY ELEMENTS:
  • A slider: Create a slider a in the range from -2 to 7 with a step size of 0.1. Hide the label completely.
  • A number: Let b = 10^a.
  • A text box: Define a text box with the text "b = b", where b is the dynamic object b slected from the drop-down objects menu in the text box dialogue.

Screencast of construction

More examples