Re: [eigen] gdb pretty quaternion and vector printing

[Benoit Jacob <jacob.benoit.1@xxxxxxxxx>]

Very nice contribution!

Could you make a proper patch as explained here:
http://eigen.tuxfamily.org/index.php?title=Developer's_Corner#Generating_a_patch

This gets you credited and spares us the effort.

Benjamin, can you confirm that this is OK for you ? and works for you ?

Thanks,
Benoit


2010/4/20 Daniel Lowengrub <lowdanie@xxxxxxxxx>:
> Hi,
> I've been using the gdb-python pretty printing support as described here:
> http://listengine.tuxfamily.org/lists.tuxfamily.org/eigen/2009/12/msg00066.html
> I added two things to the printers.py file:
> 1) When the type is has a single column or row then the variable is
> displayed as a vector like this:
> [0] = x
> [1] = y
> ...
> instead of the current:
> [0,0] = x
> [1,0] = y
> ...
>
> 2) Support for quaternions has been added.  They output looks like this:
> Eigen::Quaternion<double> (data ptr: 0xbffff440) = {
> [x] = 0.0079
> [y] = 0.0345
> [z] = 0.0364
> [w] = 0.9942}
>
> Cheers,
> Daniel Lowengrub
> ------------------------------------
>
> import gdb
> import re
> import itertools
>
>
> class EigenMatrixPrinter:
>        "Print Eigen Matrix of some kind"
>
>        def __init__(self, val):
>                "Extract all the necessary information"
>                # The gdb extension does not support value template arguments - need
> to extract them by hand
>                type = val.type
>                if type.code == gdb.TYPE_CODE_REF:
>                        type = type.target()
>                self.type = type.unqualified().strip_typedefs()
>                tag = self.type.tag
>                regex = re.compile('\<.*\>')
>                m = regex.findall(tag)[0][1:-1]
>                template_params = m.split(',')
>                template_params = map(lambda x:x.replace(" ", ""), template_params)
>
>                self.rows = int(template_params[1])
>                self.cols = int(template_params[2])
>                self.options = 0 # default value
>                if len(template_params) > 3:
>                        self.options = template_params[3];
>
>                self.rowMajor = (int(self.options) & 0x1)
>
>                if self.rows == 10000:
>                        self.rows = val['m_storage']['m_rows']
>
>                if self.cols == 10000:
>                        self.cols = val['m_storage']['m_cols']
>
>                self.innerType = self.type.template_argument(0)
>
>                self.val = val
>
>                # Fixed size matrices have a struct as their storage, so we need to
> walk through this
>                self.data = self.val['m_storage']['m_data']
>                if self.data.type.code == gdb.TYPE_CODE_STRUCT:
>                        self.data = self.data['array']
>                        self.data = self.data.cast(self.innerType.pointer())
>
>        class _iterator:
>                def __init__ (self, rows, cols, dataPtr, rowMajor):
>                        self.rows = rows
>                        self.cols = cols
>                        self.dataPtr = dataPtr
>                        self.currentRow = 0
>                        self.currentCol = 0
>                        self.rowMajor = rowMajor
>
>                def __iter__ (self):
>                        return self
>
>                def next(self):
>
>                        row = self.currentRow
>                        col = self.currentCol
>                        if self.rowMajor == 0:
>                                if self.currentCol >= self.cols:
>                                        raise StopIteration
>
>                                self.currentRow = self.currentRow + 1
>                                if self.currentRow >= self.rows:
>                                        self.currentRow = 0
>                                        self.currentCol = self.currentCol + 1
>                        else:
>                                if self.currentRow >= self.rows:
>                                        raise StopIteration
>
>                                self.currentCol = self.currentCol + 1
>                                if self.currentCol >= self.cols:
>                                        self.currentCol = 0
>                                        self.currentRow = self.currentRow + 1
>
>
>                        item = self.dataPtr.dereference()
>                        self.dataPtr = self.dataPtr + 1
>                        if (self.cols == 1): #if it's a column vector
>                                return ('[%d]' % (row,), item)
>                        elif (self.rows == 1): #if it's a row vector
>                                return ('[%d]' % (col,), item)
>                        return ('[%d,%d]' % (row, col), item)
>
>        def children(self):
>
>                return self._iterator(self.rows, self.cols, self.data, self.rowMajor)
>
>        def to_string(self):
>                return "Eigen::Matrix<%s,%d,%d,%s> (data ptr: %s)" %
> (self.innerType, self.rows, self.cols, "RowMajor" if self.rowMajor
> else  "ColMajor", self.data)
>
> class EigenQuaternionPrinter:
>        "Print an Eigen Quaternion"
>
>        def __init__(self, val):
>                "Extract all the necessary information"
>                # The gdb extension does not support value template arguments - need
> to extract them by hand
>                type = val.type
>                if type.code == gdb.TYPE_CODE_REF:
>                        type = type.target()
>                self.type = type.unqualified().strip_typedefs()
>                self.innerType = self.type.template_argument(0)
>                self.val = val
>
>                # Quaternions have a struct as their storage, so we need to walk through this
>                self.data = self.val['m_coeffs']['m_storage']['m_data']['array']
>                self.data = self.data.cast(self.innerType.pointer())
>
>        class _iterator:
>                def __init__ (self, dataPtr):
>                        self.dataPtr = dataPtr
>                        self.currentElement = 0
>                        self.elementNames = ['x', 'y', 'z', 'w']
>
>                def __iter__ (self):
>                        return self
>
>                def next(self):
>                        element = self.currentElement
>
>                        if self.currentElement >= 4: #there are 4 elements in a quanternion
>                                raise StopIteration
>
>                        self.currentElement = self.currentElement + 1
>
>                        item = self.dataPtr.dereference()
>                        self.dataPtr = self.dataPtr + 1
>                        return ('[%s]' % (self.elementNames[element],), item)
>
>        def children(self):
>
>                return self._iterator(self.data)
>
>        def to_string(self):
>                return "Eigen::Quaternion<%s> (data ptr: %s)" % (self.innerType, self.data)
>
> def build_eigen_dictionary ():
>        pretty_printers_dict[re.compile('^Eigen::Quaternion<.*>$')] = lambda
> val: EigenQuaternionPrinter(val)
>        pretty_printers_dict[re.compile('^Eigen::Matrix<.*>$')] = lambda val:
> EigenMatrixPrinter(val)
>
> def register_eigen_printers(obj):
>        "Register eigen pretty-printers with objfile Obj"
>
>        if obj == None:
>                obj = gdb
>        obj.pretty_printers.append(lookup_function)
>
> def lookup_function(val):
>        "Look-up and return a pretty-printer that can print va."
>
>        type = val.type
>
>        if type.code == gdb.TYPE_CODE_REF:
>                type = type.target()
>
>        type = type.unqualified().strip_typedefs()
>
>        typename = type.tag
>        if typename == None:
>                return None
>
>        for function in pretty_printers_dict:
>                if function.search(typename):
>                        return pretty_printers_dict[function](val)
>
>        return None
>
> pretty_printers_dict = {}
>
> build_eigen_dictionary ()
>
>
>