2.6 PND class

The PND class is rather similar to the P0D, but now data are stored in a multidimensional array. This class does not have also any graphical attributes, since it was mainly designed for data manipulations. To plot data as a histogram, one should convert a raw or column to a P0D object.

To construct a P0D and add some values, use:

>>> from jhplot  import P0D
>>>
>>> p0=PND("example",dimension) # build a PND object
>>> p0.add([1,2,3])             # append some values
>>> p0.add([2,3,4])
>>> p0.add(P0D p0d)             # append P0D object
>>> p0.set(i,[1,2,3])           # set (replace) at position i
>>> p0.set(i,P0D p0d)           # set (replace) P0D object at position i
>>> # here are fast methods to fill P0D:
>>> array=p0.getArray(index)     # get array[] at raw index 
>>> p0.setArray(array[][])       # fill with numbers from an array
>>> p0.clear()                   # clear
>>> p0.size()                    # get size (number of rows)
>>> p0.getDimension()            # get dimension
>>> m=get(row,column)            # get a value at row and column
>>> p0=PND("example",dimension,file) # build a PND object from a file

As before, avoid operations with primitive types like add() or set() to make a program faster. All other classes are rather similar to the P0D. For example, to write data to a file, use:

>>> p0.toFile("file name") # output to a file

One can easily get an array from a certain column or a row in form of P0D using the following methods:

>>> p0.getRaw(index)    # get a row at index as P0D
>>> p0.getColumn(index) # get a column at index as P0D

Once P0D is obtained, one can make a histogram using P0D method getH1D(). Look at the API to learn more about the PND methods.