python - Can I specify field names in a compact record dtype creation? -


in numpy, dtype('i4, (5)f8') short dtype([('f0', '<i4'), ('f1', '<f8', (5,))]), documented @ specifying , constructing data types:

numarray introduced short-hand notation specifying format of record comma-separated string of basic formats.

a basic format in context optional shape specifier followed array-protocol type string. parenthesis required on shape if has more 1 dimension. numpy allows modification on format in string can uniquely identify type can used specify data-type in field. generated data-type fields named 'f0', 'f1', ..., 'f' n (>1) number of comma-separated basic formats in string. if optional shape specifier provided, data-type corresponding field describes sub-array.

my question is: there shorthand notation if want name fields explicitly? example, dtype([("spam", "f4", (3,)), ("eggs", "f8", (2,2))])?

http://docs.scipy.org/doc/numpy/reference/generated/numpy.dtype.html

several examples user defined field names:

using array-protocol type strings: >>> np.dtype([('a','f8'),('b','s10')])

...

using tuples. int fixed type, 3 field’s shape. void flexible type, here of size 10: >>> np.dtype([('hello',(np.int,3)),('world',np.void,10)])

...

using dictionaries. 2 fields named ‘gender’ , ‘age’: >>> np.dtype({'names':['gender','age'], 'formats':['s1',np.uint8]})

but no evidence of syntax adding names 'i4, (5)f8' input. next step see if can find code parses dtype inputs.

numpy/core/records.py seems of dtype creation. numpy/core/_internal.py _commastring parses 'short cut'.

it uses:

format_re = re.compile(asbytes(                        r'(?p<order1>[<>|=]?)'                        r'(?p<repeats> *[(]?[ ,0-9l]*[)]? *)'                        r'(?p<order2>[<>|=]?)'                        r'(?p<dtype>[a-za-z0-9.]*(?:\[[a-za-z0-9,.]+\])?)'))

to parse string. doesn't names. guess written numarray, numpy predecessor did not use fieldnames. shouldn't hard write own parser. :)


Comments

Post a Comment

Popular posts from this blog

commonjs - How to write a typescript definition file for a node module that exports a function? -

consider, toml node module can use: // toml.d.ts declare module toml { export function parse(value:string):any; } declare module "toml" { export = toml; } then: /// <reference path="../../../../../defs/toml/toml.d.ts"/> import toml = require('toml'); toml.parse(...); however, node module export single function, such 'glob' ( https://github.com/isaacs/node-glob ). the node usage of module be: var glob = require("glob") glob("*.js", {}, callback(err, files) { ... }); you'd naively expect this: // glob.d.ts declare function globs(paths:string, options:any, callback:{(err:any, files:string[]):void; ...but because typescripts 'import' semantics bit strange, seems can use 'import .. = require()' statement alias modules . trying call: /// <reference path="../../../../../defs/glob/glob.d.ts"/> import blog = require('glob'); results in: error ts2072: mod
Read more

openid - Okta: Failed to get authorization code through API call -

i'm integrating okta own idp server using okta's api. i'm implementing authorization code flow following steps below: in own server, use /api/v1/authn endpoint sessiontoken. use sessiontoken obtain authorization calling endpoint: /oauth2/v1/authorize?client_id=" + clientid + "&sessiontoken=" + sessiontoken + "&response_type=code&response_mode=query&scope=openid&redirect_uri=" + redirecturl + "&state=evanyang&nonce=" it's supposed return response status code 302 , location header containing redirect url code value. however, keep getting response status code 200 , without location header, html body saying "you using unsupported browser." , "javascript disabled on browser." according api documentation: http://developer.okta.com/docs/api/resources/oidc.html#authentication-request , sessiontoken parameter sufficient this: an okta one-time sessiontoken. allows api-based
Read more

thorough guide for profiling racket code -

did googling ("racket profiling", "racket measure performance"), didn't find , there no examples in docs. did google "profile" search on htdp - no luck. (profile (f ...)) output isn't obvious other small snippets. ideally want python's python -m cprofile usage examples. when search "python profiling", both duckduckgo , google give top result: 26.4. python profilers . (although scanned quickly, seems more of reference "thorough usage guide" examples. if had else in mind, perhaps please link that?) the equivalent racket documentation be: profile: statistical profiler . a usage example: #lang racket (require profile) (profile-thunk (thunk (function-to-profile arg0 arg1) )) here (thunk e) convenience (lambda () e) . bigger example: #lang racket (module mod racket (provide f) (define (f) (for/list ([i 10000]) i))) (require (prefix-in mod: 'mod)) (define (f) (for ([i 10000
Read more