Array creation routines¶
See also
Ones and zeros¶
empty(shape[, dtype, order]) | Return a new array of given shape and type, without initializing entries. |
empty_like(a[, dtype, order, subok]) | Return a new array with the same shape and type as a given array. |
eye(N[, M, k, dtype]) | Return a 2-D array with ones on the diagonal and zeros elsewhere. |
identity(n[, dtype]) | Return the identity array. |
ones(shape[, dtype, order]) | Return a new array of given shape and type, filled with ones. |
ones_like(a[, dtype, order, subok]) | Return an array of ones with the same shape and type as a given array. |
zeros(shape[, dtype, order]) | Return a new array of given shape and type, filled with zeros. |
zeros_like(a[, dtype, order, subok]) | Return an array of zeros with the same shape and type as a given array. |
full(shape, fill_value[, dtype, order]) | Return a new array of given shape and type, filled with fill_value. |
full_like(a, fill_value[, dtype, order, subok]) | Return a full array with the same shape and type as a given array. |
From existing data¶
array(object[, dtype, copy, order, subok, ndmin]) | Create an array. |
asarray(a[, dtype, order]) | Convert the input to an array. |
asanyarray(a[, dtype, order]) | Convert the input to an ndarray, but pass ndarray subclasses through. |
ascontiguousarray(a[, dtype]) | Return a contiguous array in memory (C order). |
asmatrix(data[, dtype]) | Interpret the input as a matrix. |
copy(a[, order]) | Return an array copy of the given object. |
frombuffer(buffer[, dtype, count, offset]) | Interpret a buffer as a 1-dimensional array. |
fromfile(file[, dtype, count, sep]) | Construct an array from data in a text or binary file. |
fromfunction(function, shape, **kwargs) | Construct an array by executing a function over each coordinate. |
fromiter(iterable, dtype[, count]) | Create a new 1-dimensional array from an iterable object. |
fromstring(string[, dtype, count, sep]) | A new 1-D array initialized from raw binary or text data in a string. |
loadtxt(fname[, dtype, comments, delimiter, ...]) | Load data from a text file. |
Creating record arrays (numpy.rec)¶
Note
numpy.rec is the preferred alias for numpy.core.records.
core.records.array(obj[, dtype, shape, ...]) | Construct a record array from a wide-variety of objects. |
core.records.fromarrays(arrayList[, dtype, ...]) | create a record array from a (flat) list of arrays |
core.records.fromrecords(recList[, dtype, ...]) | create a recarray from a list of records in text form |
core.records.fromstring(datastring[, dtype, ...]) | create a (read-only) record array from binary data contained in |
core.records.fromfile(fd[, dtype, shape, ...]) | Create an array from binary file data If file is a string then that file is opened, else it is assumed to be a file object. |
Creating character arrays (numpy.char)¶
Note
numpy.char is the preferred alias for numpy.core.defchararray.
core.defchararray.array(obj[, itemsize, ...]) | Create a chararray. |
core.defchararray.asarray(obj[, itemsize, ...]) | Convert the input to a chararray, copying the data only if necessary. |
Numerical ranges¶
arange([start,] stop[, step,][, dtype]) | Return evenly spaced values within a given interval. |
linspace(start, stop[, num, endpoint, ...]) | Return evenly spaced numbers over a specified interval. |
logspace(start, stop[, num, endpoint, base, ...]) | Return numbers spaced evenly on a log scale. |
meshgrid(*xi, **kwargs) | Return coordinate matrices from coordinate vectors. |
mgrid | nd_grid instance which returns a dense multi-dimensional “meshgrid”. |
ogrid | nd_grid instance which returns an open multi-dimensional “meshgrid”. |
Building matrices¶
diag(v[, k]) | Extract a diagonal or construct a diagonal array. |
diagflat(v[, k]) | Create a two-dimensional array with the flattened input as a diagonal. |
tri(N[, M, k, dtype]) | An array with ones at and below the given diagonal and zeros elsewhere. |
tril(m[, k]) | Lower triangle of an array. |
triu(m[, k]) | Upper triangle of an array. |
vander(x[, N, increasing]) | Generate a Vandermonde matrix. |