python - Why does my 'instance' turn into an 'ndarray' when I use Scipy optimize? -


i have written function using quantum simulation class qutip returns float. next, called scipy.optimize.fmin_cg on function. keep getting error:

attributeerror: 'numpy.ndarray' object has no attribute 'expm'

on line:

u_sq = h_sq.expm

but h_sq instance of qobj, not ndarray. if run function outside of scipy.optimize.fmin_cg, returns type 'instance'; when runs inside of fmin_cg returns type 'ndarray'.

why this? there optimization function in python respect using instances this?

here code:

from qutip import * numpy import * import scipy.optimize   def sq_fidelity(eps,n=7):     h_sq = squeez(n,eps);     print type(h_sq);     one_ph = basis(n,1);     u_sq = h_sq.expm();     squ = u_sq*one_ph;     fidelity = expect(fock_dm(n,1),squ);     return float(fidelity)   if __name__=='__main__':     print sq_fidelity(0.2);     eps = scipy.optimize.fmin_cg(sq_fidelity, x0=0.2, args=(7,));

the issue here fmin_cg passing ndarray (of length 1) objective function. can extract scalar value changing first line of sq_fidelity to:

h_sq = squeez(n, float(eps))

Comments

Post a Comment

Popular posts from this blog

jquery - Invalid Assignment Left-Hand Side -

i trying assign class tag via jquery, resulting in error through firebug says "invalid assignment left-hand side" on fourth line below. <cfoutput> $('.pngfix a').each(function(index) { var hreflink = $(this).attr("href"); if (hreflink.tolowercase() = '../audio.cfm') { $(this).addclass('audioimg'); } }); </cfoutput> looking around online, looks syntax problem, don't seem see it... any tips? thanks if (hreflink.tolowercase() = '../audio.cfm') that attempts assign value, rather check equality. change = operator == .
Read more

java - Play! framework 2.0: How to display multiple image? -

i need display gallery of photos. here template: @(photos: list[photo]) @title = { <bold>gallery</bold> } @main(title,"photo"){ <ul class="thumbnails"> @for(photo <- photos) { <li class="span3"> <a href="#" class="thumbnail"> <img src="@photo.path" alt=""> </a> </li> } </ul> } and here controller method: public static result getphotos() { return ok(views.html.photo.gallery.render(photo.get())); } and here photo bean : @entity public class photo extends model { @id public long id; @required public string label; public string path; public photo(string path, string label) { this.path = path; this.label = label; } private static finder<long, photo> find = new finder<long, photo>( long.class, photo.class); public static list<phot...
Read more

gmail - Is there any documentation for read-only access to the Google Contacts API? -

i want read-only access user's google contacts. there stackoverflow member wanted this, , received following answer : yes, there is, use https://www.googleapis.com/auth/contacts.readonly scope , "view contacts". this exchange reference read-only access google contacts can find using google. simply using access token obtained attempt read usual google contacts api (i.e. https://www.google.com/m8/feeds ) fails insufficient permissions. similarly, using google contacts api on new target fails 404 errors (for example https://www.googleapis.com/auth/contacts.readonly/default/full ). is there documentation anywhere on how use api, or permissible way access google contacts api full read-write access?
Read more