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Prefixes for Units

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Prefixes for units of measurement

In all tables, the valid identifiers for units that can be used in TOP-Energy are highlighted in bold type.

SI Prefixes

SI prefixes are decimal prefixes defined for use in the International System of Units (SI). They are based on powers of ten with integer exponents. Both the name and the internationally uniform symbol can be used as identifiers.

Identifier (name) Identifier (symbol) Comment Definition
yotta Y Greek or Latin: octo (eight) 1024
zetta Z Latin: septem (seven) 1021
exa E Greek: hex (six) 1018
peta P Greek: pente (five) 1015
tera T Greek: teras (monster) 1012
giga G Greek: gigas (gigantic) 109
mega M Greek: megas (large) 106
myria No official SI unit. 104
kilo k Greek: chilioi (thousand) 103
hecto h Greek: hekaton (hundred) 102
deca da Greek: deka (ten) 101
deka da Greek: deka (ten) 101
deci d Latin: decimus (tenth) 10-1
centi c Latin: centum (hundred) 10-2
milli m Latin: mille (thousand) 10-3
micro Latin: micro or Greek: mikros (small) 10-6
nano n Latin: nanus or Greek: nanos (dwarf) 10-9
pico p Spanish: pico (a little) 10-12
femto f Danish or Norwegian: femten (fifteen) 10-15
atto a Danish or Norwegian: atten (eighteen) 10-18
zepto z Latin: septem (seven) 10-21
yocto y Greek or Latin: octo (eight) 10-24

Further Prefixes

Some other prefixes are used, for example, as prefixes for monetary units.

Identifier Comment Definition
Mrd billions 109
Mio millions 106
triple 3
treble 3
double 2
semi 0,5
demi 0,5
hemi 0,5
half 0,5
quarter 0,25

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