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) | 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() | Returns 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) | Return an array of zeros 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) | 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]) | Return a new 1-D array initialized from raw binary or text data in 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 |
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([dtype]) | Return evenly spaced values within a given interval. |
| linspace(start, stop[, num, endpoint, retstep]) | Return evenly spaced numbers over a specified interval. |
| logspace(start, stop[, num, endpoint, base]) | Return numbers spaced evenly on a log scale. |
| meshgrid(x, y) | Return coordinate matrices from two 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]) | Generate a Van der Monde matrix. |
