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 . c) The first two lines of the second block of commands, could have been written as the second line of the first block of commands.  . c) The first two lines of the second block of commands, could have been written as the second line of the first block of commands. This command sets RA to a rotation that rotates a 2D image by 25 degrees around the Z-axis.

Name

Transform Class

Usage

Examples

  • Here are some examples of creating a Transform3D object. Much more will be added later.

All angles are in degrees

Creating just rotations:

  • RA=Transform3D(0,0,25); # Default is the ZXZ convention
  • RA=Transform3D(EULER_SPIDER,0,0,25); # This is the typical ZYZ convention
  • RA=Transform3D(m11,m12,m13,m21,m22,m23,m31,m32,m33) # create the transformation by entering
  • components

Creating more complicated transformations using set :

  • RA = Transform3D(); # this creates the 3D identity matrix
  • RA.set_rotation(0,0,25); # creates a matrix that will rotate 2D images by 25 degrees
  • RA.set_posttrans(Vec3f(1,0,0)); # the matrix will now also shift 1 pixel in the x-direction
  • RA.set_scale(1); # Occaisionally one will wish to rescale.

Notes:

  • a) We could have used EMAN, IMAGIC, SPIN, QUATERNION, SGIROT, MRC, XYZ, MATRIX instead of the SPIDER of EULER_SPIDER above.
  • b) There is also a set_rotation via a dictionary object, which we will explain at length soon.
  • c) The first two lines of the second block of commands, could have been written as the second line of the first block of commands. This command sets RA to a rotation that rotates a 2D image by 25 degrees around the Z-axis.
  • d) There are corresponding "get" calls to extract the information from the transformation matrices. SPARX has some of its own, that are wrappers for these get calls. More later.

Description

Purpose: to apply rotation/shift/scaling operations for 2D or 3D images via a variety of methods.

Author

P. R. Baldwin

Maintainer

P. R. Baldwin

Keywords

category 1
FUNDAMENTALS

Files

libEM

See also

Maturity

Infancy

Bugs

transformClass (last edited 2013-07-01 13:12:38 by localhost)