meaning of Scala operator "<=>" -


i new scala , have solve null error case. have been suggested use <=> solve it. google no materials or reference related it. can me understand meaning of <=> , how use it. documentation of helpful google not able find it.

specifically, meaning of below statement.

val filtereddf = df.filter(df("column") <=> (new column(literal(null))))


Comments

Post a Comment

Popular posts from this blog

php - Wordpress website dashboard page or post editor content is not showing but front end data is showing properly -

Image
recently have uploaded wordpress site onto server. have uploaded wordpress site in sub-folder under root folder ../root(domain root folder)/wordpress (where host wordpress folder). now problem content data in page or post in dashboard of wordpress admin panel not showing - see image. but data showing in front view - see image. if not browser cache issue , not issue happened tinymce editor during upgrade; try add config file: define('concatenate_scripts', false);
Read more

javascript - Twitter Bootstrap - how to add some more margin between tooltip popup and element -

Image
i have not tryed since can't understand space between tooltip , element made/added bootstrap, tooltip near element triggers tooltip event. i make tooltip opening little bit away element, add more margin tooltip , eleemnt mean. i understand how in css if possible , if possible make both right,left,top,bottom tooltips hope question clear. this how tooltips looks on app: and , how should looks after this default css tooltip on top : .tooltip.top { padding: 5px 0; margin-top: -3px; } you can override in own css : .tooltip.top { margin-top: -10px; } note code work work tooltip on top, you'll nedd adapt css 3 other orientations : .tooltip.top { margin-top: -10px; } .tooltip.right { margin-left: 10px; } .tooltip.bottom { margin-top: 10px; } .tooltip.left { margin-left: -10px; }
Read more

python - Scipy.Odr multiple variable regression -

i perform multidimensional odr scipy.odr . read api documentation, says multi-dimensionality possible, cannot make work. cannot find working example on internet , api crude , give no hints how proceed. here mwe: import numpy np import scipy.odr def linfit(beta, x): return beta[0]*x[:,0] + beta[1]*x[:,1] + beta[2] n = 1000 t = np.linspace(0, 1, n) x = np.full((n, 2), float('nan')) x[:,0] = 2.5*np.sin(2*np.pi*6*t)+4 x[:,1] = 0.5*np.sin(2*np.pi*7*t + np.pi/3)+2 e = 0.25*np.random.randn(n) y = 3*x[:,0] + 4*x[:,1] + 5 + e print(x.shape) print(y.shape) linmod = scipy.odr.model(linfit) data = scipy.odr.data(x, y) odrfit = scipy.odr.odr(data, linmod, beta0=[1., 1., 1.]) odrres = odrfit.run() odrres.pprint() it raises following exception: scipy.odr.odrpack.odr_error: number of observations not match which seems related matrix shapes, not know how must shape properly. know? firstly, in experience scipy.odr uses arrays, not matrices. library seems make large...
Read more