units package¶

The unit system.

Exported members: pamp, namp, uamp, mamp, amp, kamp, Mamp, Gamp, Tamp, kelvin, kilogram, pmetre, nmetre, umetre, mmetre, metre, kmetre, Mmetre, Gmetre, Tmetre, pmeter, nmeter, umeter, mmeter, meter … (218 more members)

allunits module¶

THIS FILE IS AUTOMATICALLY GENERATED BY A STATIC CODE GENERATION TOOL DO NOT EDIT BY HAND

Instead edit the template:

dev/tools/static_codegen/units_template.py

Exported members: metre, meter, kilogram, second, amp, ampere, kelvin, mole, mol, candle, kilogramme, gram, gramme, molar, radian, steradian, hertz, newton, pascal, joule, watt, coulomb, volt, farad, ohm … (2045 more members)

Objects

 celsius A dummy object to raise errors when celsius is used.

constants module¶

A module providing some physical units as Quantity objects. Note that these units are not imported by wildcard imports (e.g. from brian2 import *), they have to be imported explicitly. You can use import ... as ... to import them with shorter names, e.g.:

from brian2.units.constants import faraday_constant as F


The available constants are:

Constant

Symbol(s)

Brian name

Value

$$N_A, L$$

avogadro_constant

$$6.022140857\times 10^{23}\,\mathrm{mol}^{-1}$$

Boltzmann constant

$$k$$

boltzmann_constant

$$1.38064852\times 10^{-23}\,\mathrm{J}\,\mathrm{K}^{-1}$$

Electric constant

$$\epsilon_0$$

electric_constant

$$8.854187817\times 10^{-12}\,\mathrm{F}\,\mathrm{m}^{-1}$$

Electron mass

$$m_e$$

electron_mass

$$9.10938356\times 10^{-31}\,\mathrm{kg}$$

Elementary charge

$$e$$

elementary_charge

$$1.6021766208\times 10^{-19}\,\mathrm{C}$$

$$F$$

faraday_constant

$$96485.33289\,\mathrm{C}\,\mathrm{mol}^{-1}$$

Gas constant

$$R$$

gas_constant

$$8.3144598\,\mathrm{J}\,\mathrm{mol}^{-1}\,\mathrm{K}^{-1}$$

Magnetic constant

$$\mu_0$$

magnetic_constant

$$12.566370614\times 10^{-7}\,\mathrm{N}\,\mathrm{A}^{-2}$$

Molar mass constant

$$M_u$$

molar_mass_constant

$$1\times 10^{-3}\,\mathrm{kg}\,\mathrm{mol}^{-1}$$

0°C

zero_celsius

$$273.15\,\mathrm{K}$$

fundamentalunits module¶

Defines physical units and quantities

 Quantity Unit Symbol Length metre m Mass kilogram kg Time second s Electric current ampere A Temperature kelvin K Quantity of substance mole mol Luminosity candle cd

Classes

 Dimension(dims) Stores the indices of the 7 basic SI unit dimension (length, mass, etc.).
 DimensionMismatchError(description, *dims) Exception class for attempted operations with inconsistent dimensions.
 Quantity(arr[, dim, dtype, copy, force_quantity]) A number with an associated physical dimension.
 Unit(arr[, dim, scale, name, dispname, …]) A physical unit.
 Stores known units for printing in best units.

Functions

 check_units(**au) Decorator to check units of arguments passed to a function
 fail_for_dimension_mismatch(obj1[, obj2, …]) Compare the dimensions of two objects.
 Return the dimensions of any object that has them.
 get_or_create_dimension(*args, **kwds) Create a new Dimension object or get a reference to an existing one.
 Find an unscaled unit (e.g.
 Return a string representation of an appropriate unscaled unit or '1' for a dimensionless quantity.
 have_same_dimensions(obj1, obj2) Test if two values have the same dimensions.
 in_best_unit(x[, precision]) Represent the value in the “best” unit.
 in_unit(x, u[, precision]) Display a value in a certain unit with a given precision.
 Test if a value is dimensionless or not.
 Tells you if the object is a 1d number type.
 quantity_with_dimensions(floatval, dims) Create a new Quantity with the given dimensions.
 Register a new unit for automatic displaying of quantities
 Returns a new function that wraps the given function func so that it changes the dimensions of its input.
 Returns a new function that wraps the given function func so that it raises a DimensionMismatchError if the function is called on a quantity with dimensions (excluding dimensionless quantities).
 Returns a new function that wraps the given function func so that it keeps the dimensions of its input.
 Returns a new function that wraps the given function func so that it removes any dimensions from its input.

Objects

 DIMENSIONLESS The singleton object for dimensionless Dimensions.
 additional_unit_register UnitRegistry containing additional units (newton*metre, farad / metre, …)
 standard_unit_register UnitRegistry containing all the standard units (metre, kilogram, um2…)
 user_unit_register UnitRegistry containing all units defined by the user

stdunits module¶

Optional short unit names

This module defines the following short unit names:

mV, mA, uA (micro_amp), nA, pA, mF, uF, nF, nS, mS, uS, ms, Hz, kHz, MHz, cm, cm2, cm3, mm, mm2, mm3, um, um2, um3

Exported members: mV, mA, uA, nA, pA, pF, uF, nF, nS, uS, mS, ms, us, Hz, kHz, MHz, cm, cm2, cm3, mm, mm2, mm3, um, um2, um3 … (3 more members)

unitsafefunctions module¶

Unit-aware replacements for numpy functions.

Exported members: log(), log10(), exp(), expm1(), log1p(), exprel(), sin(), cos(), tan(), arcsin(), arccos(), arctan(), sinh(), cosh(), tanh(), arcsinh(), arccosh(), arctanh(), diagonal(), ravel(), trace(), dot(), where(), ones_like(), zeros_like() … (2 more members)

Functions

 arange([start,] stop[, step,][, dtype]) Return evenly spaced values within a given interval.
 arccos(x, /[, out, where, casting, order, …]) Trigonometric inverse cosine, element-wise.
 arccosh(x, /[, out, where, casting, order, …]) Inverse hyperbolic cosine, element-wise.
 arcsin(x, /[, out, where, casting, order, …]) Inverse sine, element-wise.
 arcsinh(x, /[, out, where, casting, order, …]) Inverse hyperbolic sine element-wise.
 arctan(x, /[, out, where, casting, order, …]) Trigonometric inverse tangent, element-wise.
 arctanh(x, /[, out, where, casting, order, …]) Inverse hyperbolic tangent element-wise.
 cos(x, /[, out, where, casting, order, …]) Cosine element-wise.
 cosh(x, /[, out, where, casting, order, …]) Hyperbolic cosine, element-wise.
 diagonal(a[, offset, axis1, axis2]) Return specified diagonals.
 dot(a, b[, out]) Dot product of two arrays.
 exp(x, /[, out, where, casting, order, …]) Calculate the exponential of all elements in the input array.
 linspace(start, stop[, num, endpoint, …]) Return evenly spaced numbers over a specified interval.
 log(x, /[, out, where, casting, order, …]) Natural logarithm, element-wise.
 ravel(a[, order]) Return a contiguous flattened array.
 sin(x, /[, out, where, casting, order, …]) Trigonometric sine, element-wise.
 sinh(x, /[, out, where, casting, order, …]) Hyperbolic sine, element-wise.
 tan(x, /[, out, where, casting, order, …]) Compute tangent element-wise.
 tanh(x, /[, out, where, casting, order, …]) Compute hyperbolic tangent element-wise.
 trace(a[, offset, axis1, axis2, dtype, out]) Return the sum along diagonals of the array.
 where(condition, [x, y]) Return elements chosen from x or y depending on condition.
 Wraps a function so that it calls the corresponding method on the Quantities object (if called with a Quantities object as the first argument).