airobot.utils.common¶

airobot.utils.common.ang_in_mpi_ppi(angle)[source]¶

Convert the angle to the range [-pi, pi).

Parameters:	angle (float) – angle in radians.
Returns:	float – equivalent angle in [-pi, pi).

airobot.utils.common.clamp(n, minn, maxn)[source]¶

Clamp the input value to be in [minn, maxn].

Parameters:	n (float or int) – input value. minn (float or int) – minimum value. maxn (float or int) – maximum value.
Returns:	float or int – clamped value.

airobot.utils.common.create_folder(path, delete=True)[source]¶

Create a new folder.

Parameters:	path (str) – path of the folder. delete (bool) – if delete=True, then if the path already exists, the folder will be deleted and recreated.

airobot.utils.common.create_se3(ori, trans=None)[source]¶

Parameters:	ori (np.ndarray) – orientation in any following form: rotation matrix (shape: \([3, 3]\)) quaternion (shape: \([4]\)) euler angles (shape: \([3]\)). trans (np.ndarray) – translational vector (shape: \([3]\))
Returns:	np.ndarray – a transformation matrix (shape: \([4, 4]\))

airobot.utils.common.euler2quat(euler, axes='xyz')[source]¶

Convert euler angles to quaternion.

Parameters:

euler (list or np.ndarray) – euler angles (shape: \([3,]\)).
axes (str) – Specifies sequence of axes for rotations. 3 characters belonging to the set {‘X’, ‘Y’, ‘Z’} for intrinsic rotations (rotation about the axes of a coordinate system XYZ attached to a moving body), or {‘x’, ‘y’, ‘z’} for extrinsic rotations (rotation about the axes of the fixed coordinate system).

Returns:

np.ndarray – quaternion [x,y,z,w] (shape: \([4,]\)).

airobot.utils.common.euler2rot(euler, axes='xyz')[source]¶

Convert euler angles to rotation matrix.

Parameters:

euler (list or np.ndarray) – euler angles (shape: \([3,]\)).
axes (str) – Specifies sequence of axes for rotations. 3 characters belonging to the set {‘X’, ‘Y’, ‘Z’} for intrinsic rotations (rotation about the axes of a coordinate system XYZ attached to a moving body), or {‘x’, ‘y’, ‘z’} for extrinsic rotations (rotation about the axes of the fixed coordinate system).

Returns:

np.ndarray – rotation matrix (shape: \([3, 3]\)).

airobot.utils.common.linear_interpolate_path(start_pos, delta_xyz, interval)[source]¶

Linear interpolation in a path.

Parameters:	start_pos (list or np.ndarray) – start position ([x, y, z], shape: \([3]\)). delta_xyz (list or np.ndarray) – movement in x, y, z directions (shape: \([3,]\)). interval (float) – interpolation interval along delta_xyz. Interpolate a point every interval distance between the two end points.
Returns:	np.ndarray – waypoints along the path (shape: \([N, 3]\)).

airobot.utils.common.list_class_names(dir_path)[source]¶

Return the mapping of class names in all files in dir_path to their file path.

Parameters:	dir_path (str) – absolute path of the folder.
Returns:	dict – mapping from the class names in all python files in the folder to their file path.

airobot.utils.common.load_class_from_path(cls_name, path)[source]¶

Load a class from the file path.

Parameters:	cls_name (str) – class name. path (str) – python file path.
Returns:	Python Class – return the class A which is named as cls_name. You can call A() to create an instance of this class using the return value.

airobot.utils.common.print_blue(skk)[source]¶

print the text in blue color.

Parameters:	skk (str) – text to be printed.

airobot.utils.common.print_cyan(skk)[source]¶

print the text in cyan color.

Parameters:	skk (str) – text to be printed.

airobot.utils.common.print_green(skk)[source]¶

print the text in green color.

Parameters:	skk (str) – text to be printed.

airobot.utils.common.print_purple(skk)[source]¶

print the text in purple color.

Parameters:	skk (str) – text to be printed.

airobot.utils.common.print_red(skk)[source]¶

print the text in red color.

Parameters:	skk (str) – text to be printed.

airobot.utils.common.print_yellow(skk)[source]¶

print the text in yellow color.

Parameters:	skk (str) – text to be printed.

airobot.utils.common.quat2euler(quat, axes='xyz')[source]¶

Convert quaternion to euler angles.

Parameters:

quat (list or np.ndarray) – quaternion [x,y,z,w] (shape: \([4,]\)).
axes (str) – Specifies sequence of axes for rotations. 3 characters belonging to the set {‘X’, ‘Y’, ‘Z’} for intrinsic rotations (rotation about the axes of a coordinate system XYZ attached to a moving body), or {‘x’, ‘y’, ‘z’} for extrinsic rotations (rotation about the axes of the fixed coordinate system).

Returns:

np.ndarray – euler angles (shape: \([3,]\)).

airobot.utils.common.quat2rot(quat)[source]¶

Convert quaternion to rotation matrix.

Parameters:	quat (list or np.ndarray) – quaternion [x,y,z,w] (shape: \([4,]\)).
Returns:	np.ndarray – rotation matrix (shape: \([3, 3]\)).

airobot.utils.common.quat2rotvec(quat)[source]¶

Convert quaternion to rotation vector.

Parameters:	quat (list or np.ndarray) – quaternion [x,y,z,w] (shape: \([4,]\)).
Returns:	np.ndarray – rotation vector (shape: \([3,]\)).

airobot.utils.common.quat_inverse(quat)[source]¶

Return the quaternion inverse.

Parameters:	quat (list or np.ndarray) – quaternion [x,y,z,w] (shape: \([4,]\)).
Returns:	np.ndarray – inverse quaternion (shape: \([4,]\)).

airobot.utils.common.quat_multiply(quat1, quat2)[source]¶

Quaternion mulitplication.

Parameters:	quat1 (list or np.ndarray) – first quaternion [x,y,z,w] (shape: \([4,]\)). quat2 (list or np.ndarray) – second quaternion [x,y,z,w] (shape: \([4,]\)).
Returns:	np.ndarray – quat1 * quat2 (shape: \([4,]\)).

airobot.utils.common.rot2euler(rot, axes='xyz')[source]¶

Convert rotation matrix to euler angles.

Parameters:

rot (np.ndarray) – rotation matrix (shape: \([3, 3]\)).
axes (str) – Specifies sequence of axes for rotations. 3 characters belonging to the set {‘X’, ‘Y’, ‘Z’} for intrinsic rotations (rotation about the axes of a coordinate system XYZ attached to a moving body), or {‘x’, ‘y’, ‘z’} for extrinsic rotations (rotation about the axes of the fixed coordinate system).

Returns:

np.ndarray – euler angles (shape: \([3,]\)).

airobot.utils.common.rot2quat(rot)[source]¶

Convert rotation matrix to quaternion.

Parameters:	rot (np.ndarray) – rotation matrix (shape: \([3, 3]\)).
Returns:	np.ndarray – quaternion [x,y,z,w] (shape: \([4,]\)).

airobot.utils.common.rot2rotvec(rot)[source]¶

Convert rotation matrix to quaternion.

Parameters:	rot (np.ndarray) – rotation matrix (shape: \([3, 3]\)).
Returns:	np.ndarray – a rotation vector (shape: \([3,]\)).

airobot.utils.common.rotvec2euler(vec, axes='xyz')[source]¶

A rotation vector is a 3 dimensional vector which is co-directional to the axis of rotation and whose norm gives the angle of rotation (in radians).

Parameters:

vec (list or np.ndarray) – a rotational vector. Its norm represents the angle of rotation.
axes (str) – Specifies sequence of axes for rotations. 3 characters belonging to the set {‘X’, ‘Y’, ‘Z’} for intrinsic rotations (rotation about the axes of a coordinate system XYZ attached to a moving body), or {‘x’, ‘y’, ‘z’} for extrinsic rotations (rotation about the axes of the fixed coordinate system).

Returns:

np.ndarray – euler angles (shape: \([3,]\)).

airobot.utils.common.rotvec2quat(vec)[source]¶

A rotation vector is a 3 dimensional vector which is co-directional to the axis of rotation and whose norm gives the angle of rotation (in radians).

Parameters:	vec (list or np.ndarray) – a rotational vector. Its norm represents the angle of rotation.
Returns:	np.ndarray – quaternion [x,y,z,w] (shape: \([4,]\)).

airobot.utils.common.rotvec2rot(vec)[source]¶

A rotation vector is a 3 dimensional vector which is co-directional to the axis of rotation and whose norm gives the angle of rotation (in radians).

Parameters:	vec (list or np.ndarray) – a rotational vector. Its norm represents the angle of rotation.
Returns:	np.ndarray – rotation matrix (shape: \([3, 3]\)).

airobot.utils.common.se3_to_trans_ori(se3, ori='quat', axes='xyz')[source]¶

Parameters:

se3 (np.ndarray) – a SE(3) matrix (shape: \([4, 4]\))
ori (str) – orientation format, can be one of [‘quat’, ‘euler’, ‘matrix’, ‘rotvec’]
axes (str) – only used when ori == ‘euler’

Returns:

2-element tuple containing

np.ndarray: translational vector (shape: \([3,]\)).
np.ndarray: rotational vector/matrix.

airobot.utils.common.to_euler_angles(ori, axes='xyz')[source]¶

Convert orientation in any form (rotation matrix, quaternion, or euler angles) to euler angles (roll, pitch, yaw).

Parameters:

ori (list or np.ndarray) – orientation in any following form: rotation matrix (shape: \([3, 3]\)) quaternion (shape: \([4]\)) euler angles (shape: \([3]\)).
axes (str) – Specifies sequence of axes for rotations. 3 characters belonging to the set {‘X’, ‘Y’, ‘Z’} for intrinsic rotations (rotation about the axes of a coordinate system XYZ attached to a moving body), or {‘x’, ‘y’, ‘z’} for extrinsic rotations (rotation about the axes of the fixed coordinate system).

Returns:

np.ndarray –

euler angles (shape: \([3,]\)).: By default, it’s [roll, pitch, yaw]

airobot.utils.common.to_quat(ori)[source]¶

Convert orientation in any form (rotation matrix, quaternion, or euler angles) to quaternion.

Parameters:	ori (list or np.ndarray) – orientation in any following form: rotation matrix (shape: \([3, 3]\)) quaternion (shape: \([4]\)) euler angles (shape: \([3]\)).
Returns:	np.ndarray – quaternion [x, y, z, w](shape: \([4, ]\)).

airobot.utils.common.to_rot_mat(ori)[source]¶

Convert orientation in any form (rotation matrix, quaternion, or euler angles) to rotation matrix.

Parameters:	ori (list or np.ndarray) – orientation in any following form: rotation matrix (shape: \([3, 3]\)) quaternion (shape: \([4]\)) euler angles (shape: \([3]\)).
Returns:	np.ndarray – orientation matrix (shape: \([3, 3]\)).