version 1.2, 2002/07/18 15:52:27
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version 1.3, 2003/05/29 20:30:51
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Line 15 to exactly match the computers idea of t
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Line 15 to exactly match the computers idea of t
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default too large for some problems. |
default too large for some problems. |
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There are |
There are |
two kinds of tolerance. For some answer $a$ and a tolerance $t$, |
three kinds of tolerance. For some answer $A$ and a tolerance $T$, |
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\begin{enumerate} |
\begin{enumerate} |
\item an \textbf{Absolute} tolerance\index{absolute tolerance}\index{tolerance, absolute} |
\item an \textbf{Absolute} tolerance\index{absolute tolerance}\index{tolerance, absolute} |
will take anything in the range $a\pm t$. So if $a=10$ and $t=2$, then |
will take anything in the range $A\pm T$. So if $A=10$ and $T=2$, then |
anything between 8 and 12 is acceptable. |
anything between 8 and 12 is acceptable. |
Any number in the tolerance field \emph{without} a \textbf{\%} symbol is |
Any number in the tolerance field \emph{without} a \textbf{\%} symbol is |
an absolute tolerance. |
an absolute tolerance. |
\item a \textbf{Relative} tolerance\index{relative tolerance}\index{tolerance, relative} |
\item a \textbf{Relative} tolerance\index{relative tolerance}\index{tolerance, relative} |
will take anything in the range $a\pm at$, where \emph{t} is interpreted |
will take anything in the range $A\pm aT$, where \emph{T} is interpreted |
as a percentage. Any number in the tolerance field \emph{followed by} a \textbf{\%} |
as a percentage/100. Any number in the tolerance field \emph{followed by} a \textbf{\%} |
symbol is a relative tolerance. For example, $a=10$ and $t=10\%$ will accept |
symbol is a relative tolerance. For example, $a=10$ and $t=10\%$ will accept |
anything between 9 and 11. |
anything between 9 and 11. |
\end{enumerate} |
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\item a tolerance that is a calculated variable (identified by \$ sign as |
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the first character). For example, if an answer is $\$X$,and for a student |
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possible values range from $-\$X1$ to $+\$X1$, you could choose $T = |
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\$tolerance = \$2X1/100;$ acceptable answers would then be from |
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$\$X-\$tolerance$ to $\$X+\$tolerance$. (This is especially useful when answers |
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close to zero are possible for some students) |
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\end{enumerate} |