parmed.unit.Quantity¶

class
parmed.unit.
Quantity
(value=None, unit=None)[source]¶ Physical quantity, such as 1.3 meters per second.
Quantities contain both a value, such as 1.3; and a unit, such as ‘meters per second’.
 Supported value types include:
1  numbers (float, int, long) 2  lists of numbers, e.g. [1,2,3] 3  tuples of numbers, e.g. (1,2,3)
Note  unit conversions will cause tuples to be converted to lists
4  lists of tuples of numbers, lists of lists of … etc. of numbers 5  numpy.arrays
Methods
in_unit_system
(system)Returns a new Quantity equal to this one, expressed in a particular unit system.
in_units_of
(other_unit)Returns an equal Quantity expressed in different units.
max
(*args, **kwargs)Computes the maximum value of the sequence, with the result having the same unit as the current sequence.
mean
(*args, **kwargs)Computes the mean of a sequence, with the result having the same unit as the current sequence.
min
(*args, **kwargs)Computes the minimum value of the sequence, with the result having the same unit as the current sequence.
reduce_unit
([guide_unit])Combine similar component units and scale, to form an equal Quantity in simpler units.
reshape
(shape[, order])Same as numpy.ndarray.reshape, except the result is a Quantity with the same units as the current object rather than a plain numpy.ndarray
sqrt
()Returns square root of a Quantity.
std
(*args, **kwargs)Computes the square root of the variance of a sequence, with the result having the same unit as the current sequence.
sum
(*args, **kwargs)Computes the sum of a sequence, with the result having the same unit as the current sequence.
value_in_unit
(unit)Returns underlying value, in the specified units.
value_in_unit_system
(system)Returns the underlying value type, after conversion to a particular unit system.
append
count
extend
format
index
insert
pop
remove

__init__
(value=None, unit=None)[source]¶ Create a new Quantity from a value and a unit.
 Parameters
value: (any type, usually a number) Measure of this quantity
unit: (Unit) the physical unit, e.g. simtk.unit.meters.
Methods
__init__
([value, unit])Create a new Quantity from a value and a unit.
append
(item)count
(item)extend
(rhs)format
(format_spec)in_unit_system
(system)Returns a new Quantity equal to this one, expressed in a particular unit system.
in_units_of
(other_unit)Returns an equal Quantity expressed in different units.
index
(item)insert
(index, item)max
(*args, **kwargs)Computes the maximum value of the sequence, with the result having the same unit as the current sequence.
mean
(*args, **kwargs)Computes the mean of a sequence, with the result having the same unit as the current sequence.
min
(*args, **kwargs)Computes the minimum value of the sequence, with the result having the same unit as the current sequence.
pop
(*args)reduce_unit
([guide_unit])Combine similar component units and scale, to form an equal Quantity in simpler units.
remove
(item)reshape
(shape[, order])Same as numpy.ndarray.reshape, except the result is a Quantity with the same units as the current object rather than a plain numpy.ndarray
sqrt
()Returns square root of a Quantity.
std
(*args, **kwargs)Computes the square root of the variance of a sequence, with the result having the same unit as the current sequence.
sum
(*args, **kwargs)Computes the sum of a sequence, with the result having the same unit as the current sequence.
value_in_unit
(unit)Returns underlying value, in the specified units.
value_in_unit_system
(system)Returns the underlying value type, after conversion to a particular unit system.