c4dynamics.states.state.state.data

state.data(var=None, scale=1.0)

Returns arrays of stored time and data.

data() returns a tuple containing two numpy arrays: the first consists of timestamps, and the second contains the values of a var corresponding to those timestamps.

var may be each one of the state variables or the parameters.

If var is not introduced, data() returns a single array of the entire state histories.

If data were not stored, data() returns an empty array.

Parameters:

• var (str) – The name of the variable or parameter of the required histories.

• scale (float or int, optional) – A scaling factor to apply to the variable values, by default 1.

Returns:

out (array or tuple of numpy arrays) – if var is introduced, out is a tuple of a timestamps array and an array of var values corresponding to those timestamps. If var is not introduced, then \(n \times m+1\) numpy array is returned, where n is the number of stored samples, and m+1 is the number of state variables and times.

Examples

Get all stored data:

>>> np.random.seed(100) # to reproduce results
>>> s = c4d.state(x = 1, y = 0, z = 0)
>>> for t in np.linspace(0, 1, 3):
...   s.X = np.random.rand(3)
...   s.store(t)
>>> s.data() 
[[0.   0.543  0.278  0.424]
 [0.5  0.845  0.005  0.121]
 [1.   0.671  0.826  0.137]]

Data of a variable:

>>> time, x_data = s.data('x')
>>> time  
[0.  0.5  1.]
>>> x_data  
[0.543  0.845  0.671]
>>> s.data('y')[1]  
[0.278  0.005  0.826]

Get data with scaling:

>>> s = c4d.state(phi = 0)
>>> for p in np.linspace(0, c4d.pi):
...   s.phi = p
...   s.store()
>>> s.data('phi', c4d.r2d)[1]  
[0  3.7  7.3  ...  176.3  180]

Data of a parameter

>>> s = c4d.state(x = 100, vx = 10)
>>> s.mass = 25
>>> s.storeparams('mass', t = 0.1)
>>> s.data('mass')
(array([0.1]), array([25.]))