Reference documentation for deal.II version 9.5.0

#include <deal.II/numerics/histogram.h>
Classes  
struct  Interval 
Public Types  
enum  IntervalSpacing { linear , logarithmic } 
Public Member Functions  
template<typename number >  
void  evaluate (const std::vector< Vector< number > > &values, const std::vector< double > &y_values, const unsigned int n_intervals, const IntervalSpacing interval_spacing=linear) 
template<typename number >  
void  evaluate (const Vector< number > &values, const unsigned int n_intervals, const IntervalSpacing interval_spacing=linear) 
void  write_gnuplot (std::ostream &out) const 
std::size_t  memory_consumption () const 
Static Public Member Functions  
static std::string  get_interval_spacing_names () 
static IntervalSpacing  parse_interval_spacing (const std::string &name) 
static ::ExceptionBase &  ExcEmptyData () 
static ::ExceptionBase &  ExcIncompatibleArraySize (int arg1, int arg2) 
static ::ExceptionBase &  ExcInvalidName (std::string arg1) 
Static Private Member Functions  
template<typename number >  
static bool  logarithmic_less (const number n1, const number n2) 
Private Attributes  
std::vector< std::vector< Interval > >  intervals 
std::vector< double >  y_values 
This class provides some facilities to generate 2d and 3d histograms. It is used by giving it one or several data sets and a rule how to break the range of values therein into intervals (e.g. linear spacing or logarithmic spacing of intervals). The values are then sorted into the different intervals and the number of values in each interval is stored for output later. In case only one data set was given, the resulting histogram will be a 2d one, while it will be a 3d one if more than one data set was given. For more than one data set, the same intervals are used for each of them anyway, to make comparison easier.
At present, the following schemes for interval spacing are implemented:
To keep programs extensible, you can use the two functions get_interval_spacing_names
and parse_interval_spacing
, which always give you a complete list of spacing formats presently supported and are able to generate the respective value of the enum
. If you use them, you can write your program in a way such that it only needs to be recompiled to take effect of newly added formats, without changing your code.
At present, only GNUPLOT output is supported.
Definition at line 71 of file histogram.h.
Definition of several ways to arrange the spacing of intervals.
Enumerator  

linear  Space intervals linearly. 
logarithmic  Space intervals logarithmically. 
Definition at line 77 of file histogram.h.
void Histogram::evaluate  (  const std::vector< Vector< number > > &  values, 
const std::vector< double > &  y_values,  
const unsigned int  n_intervals,  
const IntervalSpacing  interval_spacing = linear 

) 
Take several lists of values, each on to produce one histogram that will then be arrange one behind each other.
Using several data sets at once allows to compare them more easily, since the intervals into which the data is sorted is the same for all data sets.
The histograms will be arranged such that the computed intervals of the values[i][j]
form the xrange, and the number of values in each interval will be the yrange (for 2d plots) or the zrange (for 3d plots). For 3d plots, the y_values
parameter is used to assign each data set a value in the y direction, which is the depth coordinate in the resulting plot. For 2d plots, the y_values
are ignored.
If you give only one data set, i.e. values.size()==1
, then the resulting histogram will be a 2d one.
n_intervals
denotes the number of intervals into which the data will be sorted; interval_spacing
denotes the way the bounds of the intervals are computed. Refer to the general documentation for more information on this.
Definition at line 56 of file histogram.cc.
void Histogram::evaluate  (  const Vector< number > &  values, 
const unsigned int  n_intervals,  
const IntervalSpacing  interval_spacing = linear 

) 
This function is only a wrapper to the above one in case you have only one data set.
Definition at line 211 of file histogram.cc.
void Histogram::write_gnuplot  (  std::ostream &  out  )  const 
Write the histogram computed by the evaluate
function to a stream in a format suitable to the GNUPLOT program. The function generates 2d or 3d histograms.
Definition at line 225 of file histogram.cc.

static 
Return allowed names for the interval spacing as string. At present this is "linearlogarithmic".
Definition at line 279 of file histogram.cc.

static 
Get a string containing one of the names returned by the above function and return the respective value of IntervalSpacing
. Throw an error if the string is no valid one.
Definition at line 287 of file histogram.cc.
std::size_t Histogram::memory_consumption  (  )  const 
Determine an estimate for the memory consumption (in bytes) of this object.
Definition at line 304 of file histogram.cc.

staticprivate 
"Lessthan" operation which finds the minimal positive value by sorting zero and negative value to be larger than the largest positive number. Used to find the lower bound of the leftmost interval in the logarithmic case interval spacing scheme.
Return true
, if (n1<n2
, and (n1>0
or n2<0
)), or (n2<n1 and n1>0 and n2<=0). This in effect sorts all negative numbers to be larger than the largest positive number.
Definition at line 30 of file histogram.cc.

private 
Vector holding one set of intervals for each data set given to the evaluate
function.
Definition at line 235 of file histogram.h.

private 
Values for the depth axis of 3d histograms. Stored in the evaluate
function.
Definition at line 241 of file histogram.h.