nan

The default behavior for the JSON encoder is to convert NaNs to 'NaN', e.g. json.dumps(np.NaN) results in 'NaN'. How can I change this 'NaN' value to 'null'? I have tried to subclass the JSONEncoder and implement the default() method as follows: from json import JSONEncoder, dumps import numpy as np class NanConverter(JSONEncoder): def default(self, obj): try: _ = iter(obj) except TypeError: if isinstance(obj, float) and np.isnan(obj): return "null" return JSONEncoder.default(self, obj) >>> d = {'a': 1, 'b': 2, 'c': 3, 'e': np.nan, 'f': [1, np.nan, 3]} >>> dumps(d, cls=NanConverter) '{"a": 1,

I'm importing some data from a csv file. The file has nan values flagged with text 'NA'. I import the data with: X = genfromtxt(data, delimiter=',', dtype=float, skip_header=1) I the use this code to replace nan with a previosly calculated column mean. inds = np.where(np.isnan(X)) X[inds]=np.take(col_mean,inds[1]) I then run a couple of checks and get empty arrays: np.where(np.isnan(X)) np.where(np.isinf(X)) Finally I run a scikit classifier: RF = ensemble.RandomForestClassifier(n_estimators=100,n_jobs=-1,verbose=2) RF.fit(X, y) and get the following error: File "C:\Users\m&g\Anaconda\lib\site

I have a data frame with several factor columns containing NaN 's that I would like to convert to NA 's (the NaN seems to be a problem for using linear regression objects to predict on new data). > tester1 <- c("2", "2", "3", "4", "2", "3", NaN) > tester1 [1] "2" "2" "3" "4" "2" "3" "NaN" > tester1[is.nan(tester1)] = NA > tester1 [1] "2" "2" "3" "4" "2" "3" "NaN" > tester1[is.nan(tester1)] = "NA" > tester1 [1] "2" "2" "3" "4" "2" "3" "NaN" Here's the problem: Your vector is character in mode, so of course it's "not a number". That last element got interpreted as the string "NaN". Using is.nan

Most Json parsers don't serialize NaN, because in Javascript, NaN is not a constant. Json.Net, however, does serialize NaN values into NaN, which means it outputs invalid Json; attempting to deserialize this Json will fail with most parsers. (We're deserializing in WebKit.) We have hacked the Json.Net code to output null values when passed NaN, but this seems like a poor solution. Douglas Crockford (once) recommended using nulls in place of NaNs: http://www.json.org/json.ppt (Look at slide 16) Clearly this won't work in all cases, but it would be ok for our purposes. We'd just rather not have

I'm writing Python 2.6 code that interfaces with NI TestStand 4.2 via COM in Windows. I want to make a "NAN" value for a variable, but if I pass it float('nan') , TestStand displays it as IND . Apparently TestStand distinguishes between floating point "IND" and "NAN" values. According to TestStand help : IND corresponds to Signaling NaN in Visual C++, while NAN corresponds to QuietNaN That implies that Python's float('nan') is effectively a Signaling NaN when passed through COM. However, from what I've read about Signaling NaN , it seems that Signaling NaN is a bit "exotic" and Quiet NaN is