defined prefix can be applied to metric units, e.g. kg for
kilo gram (where k is the prefix and g is the base unit).
Simple units may be
raised to a power by appending an integer number to the end of the
unit term. Negative exponents must be preceded by a minus sign ('-'). Positive exponents may be
preceded by a plus sign ('+') although the sign may be omitted.
All units can be combined in an
algebraic term using the operators for multiplication (period '.') and division (solidus '/').
No blanks are allowed within the unit expression.
Multiple terms in an expression must be separated by an arithmetic
operator - either the multiplication operator (.) or the division
The multiplication operator (.) must be explicity specified; it is never
While the multiplication operator (.) must appear between two unit terms,
the division operator (/) may appear at the beginning of the expression,
indicating inversion of the following term. However, the division
operator normally appears between two terms.
Terms are evaluated from left to right, with multiplication and
division having the same precedence.
may be used to override normal left-to-right evaluation
of an expreession. For example kg/m.s2 divides kg by m and multiplies the
result by s2. kg/(m.s2) multiplies m by s2 and divides that by kg.
Validate all unit expressions in a CSV file
We can validate unit expressions in a comma separated
values file on your system.
Use the browse button below to select the file.
You will then be asked for the name of the column that contains
the expressions to be validated. (Your file must include column
A copy of your file will be created that includes three
additional columns at the end, confirming what expression was
validated, the validation results, and any relevant notes.
You will be asked where you want the file saved. You may
change the name of the output file at that time.
Note that this will only validate unit expressions.
Although prefixes used with a unit code, e.g., "kL" (kiloliter),
are recognized as prefixes ("k" for kilo) modifying a unit code
("L" for liter), a prefix submitted by itself, e.g., "E" (exa)
will result in an "invalid unit code" return.
Name of the column that contains the expressions to be validated
About the LHC UCUM Library
Here is a description of the LHC UCUM