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# Array creation routines

See also

Array creation

## Ones and zeros

`empty` (shape[, dtype, order]) | Return a new array of given shape and type, without initialising entries.
`empty_like` (a) | Create a new array with the same shape and type as another.
`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` (x[, out]) | 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) | Returns an array of zeros with the same shape and type as a given array.

## From existing data

`array` (object[, dtype, copy, order, ...]) | Create an array.
`asarray` (a[, dtype, order]) | Convert the input to an array.
`asanyarray` (a[, dtype, order]) | Convert the input to a 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.
`loadtxt` (fname[, dtype, comments, ...]) | 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, offset, ...]) | Construct a record array from a wide-variety of objects.
`core.records.fromarrays` (arrayList[, dtype, shape, formats, ...]) | create a record array from a (flat) list of arrays
`core.records.fromrecords` (recList[, dtype, shape, formats, ...]) | create a recarray from a list of records in text form
`core.records.fromstring` (datastring[, dtype, shape, offset, ...]) | create a (read-only) record array from binary data contained in a string
`core.records.fromfile` (fd[, dtype, shape, offset, ...]) | 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, copy, ...]) |

## Numerical ranges

`arange` ([start,] stop[, step, ...]) | 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` | Construct a multi-dimensional filled “meshgrid”.

## Building matrices

`diag` (v[, k]) | Extract a diagonal or construct a diagonal array.
`diagflat` (v[, k]) | Create a 2-dimensional array with the flattened input as a diagonal.
`tri` (N[, M, k, dtype]) | Construct an array filled with ones at and below the given diagonal.
`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.

## The Matrix class

`mat` (data[, dtype]) | Interpret the input as a matrix.
`bmat` (obj[, ldict, gdict]) | Build a matrix object from a string, nested sequence, or array.

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