Number Manipulation On Linux
Significant Figures
The following code calculates a number to 3 significant figures.
typeset -E3 newvar=$MyVariable
Example
#Calculate to 3 Significant Figure
MyVariable=123.4567
typeset -E3 newvar=$MyVariable
echo $newvar
123
For 5 significant figures change -E3 to -E5
Example
#Calculate to 5 Significant Figure
MyVariable=123.4567
typeset -E5 newvar=$MyVariable
echo $newvar
123.46
Expanding Scientific Notation
When Calculating large numbers to significant figures, the number may be converted to scientific notation. This is not useful if used in a script. The following example shows how to expand scientific notation.
Example
#Calculate to Significant Figure
MyVariable=123456.789
typeset -E1 newvar1=$MyVariable
echo $newvar1
1e+05
#Expand Scientific Notation
newvar2=`printf "%8d\n" $newvar1`
echo $newvar2
100000
