Input and output

NPZ files

load (file[, mmap_mode]) Load a pickled, .npy, or .npz binary file.
save (file, arr) Save an array to a binary file in NumPy format.
savez (file, *args, **kwds) Save several arrays into an .npz file format which is a zipped-archive of arrays

Text files

loadtxt (fname[, dtype, comments, ...]) Load data from a text file.
savetxt (fname, X[, fmt, delimiter]) Save an array to file.
fromregex (file, regexp, dtype) Construct an array from a text file, using regular-expressions parsing.
fromstring (string[, dtype, count, sep]) Return a new 1d array initialized from raw binary or text data in string.
ndarray.tofile (fid[, sep, format]) Write array to a file as text or binary.
ndarray.tolist () Return the array as a possibly nested list.

String formatting

array_repr (arr[, max_line_width, ...]) Return the string representation of an array.
array_str (a[, max_line_width, ...]) Return a string representation of an array.

Memory mapping files

memmap Create a memory-map to an array stored in a file on disk.

Text formatting options

set_printoptions ([precision, threshold, ...]) Set printing options.
get_printoptions () Return the current print options.
set_string_function (f[, repr]) Set a Python function to be used when pretty printing arrays.

Base-n representations

binary_repr (num[, width]) Return the binary representation of the input number as a string.
base_repr (number[, base, padding]) Return a string representation of a number in the given base system.

Data sources

DataSource A generic data source file (file, http, ftp, ...).