|Some Trial Tasks|
|square root √||=|
|cube root ∛||=|
The rule cursor and central slide can be positioned using a mouse. Fine adjustment can be achieved using the keyboard left and right arrow buttons. The keyboard keys move the cursor or slide depending upon which had last been clicked or adjusted.
The left hand display below the rule (“A on B” etc) shows the slide position. The central display shows the cursor position over each of the slide scales.
Why is the cursor window a bit yellow? To find out, check my blog where some of the design decisions that went into constructing this rule are described. Thats also a good place to comment if you come across any gross bugs (bugs are likely of course but so are edge cases that maybe should be treated kindly).
The “Trial Tasks” section allows you to try out some calculations that “animate” the slide rule. Just enter some suitable values and click the relevant “Calculate” button. The division calculation is managed in two steps although the second step could be omitted as the result can be observed at the end (1 or 10) of the C scale.
The calculations here are not always perfectly representative as the page sometimes reads the cursor position with greater precision than would always be possible. For the most realistic results in all cases, read the cursor position for yourself. A slide rule user had to be adept at keeping track of the magnitude of the result. Sometimes that only requires keeping track of the 10s but sometimes a rough result has to be estimated first.