A wrapper class around native java arrays.
Instances of PyArray are created either by java functions or directly by the
jarray module.
See also the jarray module.
__add__
public PyObject __add__(PyObject other)
Adds (appends) two PyArrays together
- __add__ in interface PyObject
other
- a PyArray to be added to the instance
- the result of the addition as a new PyArray instance
__findattr__
public PyObject __findattr__(String name)
Finds the attribute.
- __findattr__ in interface PyObject
name
- the name of the attribute of interest
- the value for the attribute of the specified name
__len__
public int __len__()
Length of the array
- __len__ in interface PyObject
- number of elements in the array
__repr__
public PyString __repr__()
String representation of PyArray
- __repr__ in interface PyObject
- string representation of PyArray
__tojava__
public Object __tojava__(Class c)
- __tojava__ in interface PySequence
c
- target Class for the conversion
- Java object converted to required class type if possible.
append
public void append(PyObject value)
Append new value x to the end of the array.
value
- item to be appended to the array
array
public static PyArray array(PyObject init,
Class ctype)
Create a PyArray storing ctype types and being initialised
with initialiser.
init
- an initialiser for the array - can be PyString or PySequence
(including PyArray) or iterable type.ctype
- Class
type of the elements stored in the array.
array_append
public void array_append(PyObject value)
array_byteswap
public void array_byteswap()
array_count
public int array_count(PyObject value)
array_extend
public void array_extend(PyObject iterable)
array_fromlist
public void array_fromlist(PyObject obj)
array_index
public int array_index(PyObject value)
array_insert
public void array_insert(int index,
PyObject value)
array_pop
public PyObject array_pop(int i)
array_remove
public void array_remove(PyObject value)
array_reverse
public void array_reverse()
array_tofile
public void array_tofile(PyObject f)
array_tolist
public PyObject array_tolist()
array_tostring
public PyObject array_tostring()
array_write
public void array_write(PyObject f)
byteswap
public void byteswap()
"Byteswap" all items of the array. This is only supported for values
which are 1, 2, 4, or 8 bytes in size; for other types of values,
RuntimeError is raised. It is useful when reading data from a file
written on a machine with a different byte order.
char2class
public static Class char2class(char type)
throws PyIgnoreMethodTag
Converts a character code for the array type to a Java
Class
.
The following character codes and their native types are supported:
Type code | native type |
z | boolean |
c | char |
b | byte |
h | short |
i | int |
l | long |
f | float |
d | double |
type
- character code for the array type
clone
public Object clone()
Implementation of Cloneable interface.
count
public PyInteger count(PyObject value)
Return the number of occurrences of x in the array.
value
- instances of the value to be counted
- number of time value was found in the array.
extend
public void extend(PyObject iterable)
Append items from iterable to the end of the array. If
iterable is another array, it must have exactly the same type code; if
not, TypeError will be raised. If iterable is not an array, it must be
iterable and its elements must be the right type to be appended to the
array. Changed in version 2.4: Formerly, the argument could only be
another array.
iterable
- iterable object used to extend the array
fromfile
public void fromfile(PyObject f,
int count)
Read count items (as machine values) from the file object
f and append them to the end of the array. If less than
count items are available, EOFError is raised, but the items
that were available are still inserted into the array. f must
be a real built-in file object; something else with a read() method won't
do.
f
- Python builtin file object to retrieve datacount
- number of array elements to read
fromlist
public void fromlist(PyObject obj)
Append items from the list. This is equivalent to "for x in list:
a.append(x)"except that if there is a type error, the array is unchanged.
obj
- input list object that will be appended to the array
fromstring
public void fromstring(String input)
Appends items from the string, interpreting the string as an array of
machine values (as if it had been read from a file using the
fromfile()
method).
input
- string of bytes containing array data
getArray
public Object getArray()
throws PyIgnoreMethodTag
Return the internal Java array storage of the PyArray instance
getItemsize
public int getItemsize()
Getter for the storage size of the array's type.
The sizes returned by this method represent the number of bytes used to
store the type. In the case of streams, this is the number of bytes
written to, or read from a stream. For memory this value is the
minimum number of bytes required to store the type.
This method is used by other methods to define read/write quanta from
strings and streams.
Values returned are:
Type | Size |
boolean | 1 |
byte | 1 |
char | 1 |
short | 2 |
int | 4 |
long | 8 |
float | 4 |
double | 8 |
- number of bytes used to store array type.
getTypecode
public String getTypecode()
throws PyIgnoreMethodTag
Getter for the type code of the array.
char2class
describes the possible type codes
and their meaning.
- single character type code for the array
index
public PyObject index(PyObject value)
Return the smallest i such that i is the index of
the first occurrence of value in the array.
value
- value to find the index of
- index of the first occurance of value
insert
public void insert(int index,
PyObject value)
Insert a new item with value value in the array before
position index. Negative values are treated as being relative
to the end of the array.
index
- insert positionvalue
- value to be inserted into array
pop
public PyObject pop()
Removes the item with the index index from the array and
returns it. The optional argument defaults to -1, so that by default the
last item is removed and returned.
pop
public PyObject pop(int index)
Removes the item with the index index from the array and
returns it. The optional argument defaults to -1, so that by default the
last item is removed and returned.
index
- array location to be popped from the array
- array element popped from index
remove
public void remove(PyObject value)
Remove the first occurrence of value from the array.
value
- array value to be removed
reverse
public void reverse()
Reverse the elements in the array
tofile
public void tofile(PyObject f)
Write all items (as machine values) to the file object f.
f
- Python builtin file object to write data
tolist
public PyObject tolist()
Convert the array to an ordinary list with the same items.
tostring
public String tostring()
Convert the array to an array of machine values and return the string
representation (the same sequence of bytes that would be written to a
file by the
tofile()
method.)
zeros
public static PyArray zeros(int n,
Class ctype)
zeros
public static PyArray zeros(int n,
char typecode)