Array creation routines — NumPy v2.3.dev0 Manual (original) (raw)
From shape or value#
| empty(shape[, dtype, order, device, like]) | Return a new array of given shape and type, without initializing entries. |
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| empty_like(prototype[, dtype, order, subok, ...]) | Return a new array with the same shape and type as a given array. |
| eye(N[, M, k, dtype, order, device, like]) | Return a 2-D array with ones on the diagonal and zeros elsewhere. |
| identity(n[, dtype, like]) | Return the identity array. |
| ones(shape[, dtype, order, device, like]) | Return a new array of given shape and type, filled with ones. |
| ones_like(a[, dtype, order, subok, shape, ...]) | Return an array of ones with the same shape and type as a given array. |
| zeros(shape[, dtype, order, like]) | Return a new array of given shape and type, filled with zeros. |
| zeros_like(a[, dtype, order, subok, shape, ...]) | 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, ...]) | Return a full array with the same shape and type as a given array. |
From existing data#
| array(object[, dtype, copy, order, subok, ...]) | Create an array. |
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| asarray(a[, dtype, order, device, copy, like]) | Convert the input to an array. |
| asanyarray(a[, dtype, order, device, copy, like]) | Convert the input to an ndarray, but pass ndarray subclasses through. |
| ascontiguousarray(a[, dtype, like]) | Return a contiguous array (ndim >= 1) in memory (C order). |
| asmatrix(data[, dtype]) | Interpret the input as a matrix. |
| astype(x, dtype, /, *[, copy, device]) | Copies an array to a specified data type. |
| copy(a[, order, subok]) | Return an array copy of the given object. |
| frombuffer(buffer[, dtype, count, offset, like]) | Interpret a buffer as a 1-dimensional array. |
| from_dlpack(x, /, *[, device, copy]) | Create a NumPy array from an object implementing the __dlpack__ protocol. |
| fromfile(file[, dtype, count, sep, offset, like]) | Construct an array from data in a text or binary file. |
| fromfunction(function, shape, *[, dtype, like]) | Construct an array by executing a function over each coordinate. |
| fromiter(iter, dtype[, count, like]) | Create a new 1-dimensional array from an iterable object. |
| fromstring(string[, dtype, count, like]) | A new 1-D array initialized from text data in a string. |
| loadtxt(fname[, dtype, comments, delimiter, ...]) | Load data from a text file. |
Creating record arrays#
| rec.array(obj[, dtype, shape, offset, ...]) | Construct a record array from a wide-variety of objects. |
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| rec.fromarrays(arrayList[, dtype, shape, ...]) | Create a record array from a (flat) list of arrays |
| rec.fromrecords(recList[, dtype, shape, ...]) | Create a recarray from a list of records in text form. |
| rec.fromstring(datastring[, dtype, shape, ...]) | Create a record array from binary data |
| rec.fromfile(fd[, dtype, shape, offset, ...]) | Create an array from binary file data |
Creating character arrays (numpy.char)#
Note
numpy.char is used to create character arrays.
Numerical ranges#
| arange([start,] stop[, step,][, dtype, ...]) | Return evenly spaced values within a given interval. |
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| 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. |
| geomspace(start, stop[, num, endpoint, ...]) | Return numbers spaced evenly on a log scale (a geometric progression). |
| meshgrid(*xi[, copy, sparse, indexing]) | Return a tuple of coordinate matrices from coordinate vectors. |
| mgrid | An instance which returns a dense multi-dimensional "meshgrid". |
| ogrid | An instance which returns an open multi-dimensional "meshgrid". |
Building matrices#
| diag(v[, k]) | Extract a diagonal or construct a diagonal array. |
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| diagflat(v[, k]) | Create a two-dimensional array with the flattened input as a diagonal. |
| tri(N[, M, k, dtype, like]) | 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. |
The matrix class#
| bmat(obj[, ldict, gdict]) | Build a matrix object from a string, nested sequence, or array. |
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